Integrated Invasive 

Plant Management 

for the Northwest 

Oregon District 

Environmental 

Assessment (November 2018) 

(DOI-BLM-ORWA-N000-2018-0002-EA) 

NORTHWEST OREGON

BLM

 DISTRICT November 2018

U.S. Department of the Interior 

Bureau of Land Management 

Northwest Oregon District 

1717 Fabry Road, SE

Salem, OR 97306
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Table of Contents

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Acronyms and Abbreviations

ACEC Area of Critical Environmental Concern

A.E. Acid Equivalent

A.I. Active Ingredient

ALS Acetolactate synthase

APHIS Animal and Plant Health Inspection 

Service

ARBO II Aquatic Restoration Biological Opinion 

(2013)

BEE With triclopyr, butoxyethyl ester

BLM Bureau of Land Management

CFR Code of Federal Regulations

EA Environmental Assessment

EDRR Early Detection Rapid Response

EIS Environmental Impact Statement

EPA Environmental Protection Agency

ESA Endangered Species Act

FEIS Final Environmental Impact Statement

FIFRA Federal Insecticide Fungicide 

Rodenticide Act

FLPMA Federal Land Policy and Management 

Act

FONSI Finding of No Significant Impact

FWS U.S. Fish and Wildlife Service

GIS Geographic Information System

HUC Hydrologic Unit Code

HQ Hazard Quotient

IARC International Agency for Research on 

Cancer

JMPR Joint FAO / WHO Meeting on Pesticide 

Residues

LD50 Lethal Dose to 50 percent of a 

population

LOAEL Lowest Observed Adverse Effect Level

LOC Level of Concern

MM Mitigation Measure

NEPA National Environmental Policy Act

NISIMS National Invasive Species Information

Management System

NMFS National Marine Fisheries Service

NOAEL No Observed Adverse Effect Level

NPDES National Pollutant Discharge 

Elimination System

NRHP National Register of Historic Places

ODA Oregon Department of Agriculture

ODEQ Oregon Department of Environmental 

Quality

ODFW Oregon Department of Fish and 

Wildlife

ODOT Oregon Department of Transportation

OWRD Oregon Water Resources Department

Oregon FEIS Vegetation Treatments Using 

Herbicides on BLM Lands in Oregon 

FEIS (2010)

2007 PEIS Vegetation Treatments Using Herbicides 

on BLM Landsin 17 Western States 

Programmatic FEIS (2007)

2016 PEIS Vegetation Treatments Using 

Aminopyralid, Fluroxypyr, and Rimsulfuron 

on BLM Lands in 17 Western States 

Programmatic FEIS (2016)

pH potential of Hydrogen (measure of 

acidity)

POEA Polyoxyethyleneamine, a surfactant 

found in some glyphosate formulations

PUP Pesticide Use Proposal

RfD Reference Dose

RQ Risk Quotient

SHPO State Historic Preservation Office

TEA With triclopyr, triethylamine salt

TEP Federally listed as threatened or 

endangered, or proposed for such 

listing

TI Toxicity Index

TMDL Total Maximum Daily Load

WHO World Health Organization
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Table of Contents

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Table of Contents

Chapter 1 - Purpose and Need ...............................................................................................................................5

The Need....................................................................................................................................................................7

The Purposes .............................................................................................................................................................9

Issues .........................................................................................................................................................................9

Issues Analyzed in Detail........................................................................................................................................9

Issues Not Analyzed in Detail...............................................................................................................................10

Decision to Be Made................................................................................................................................................11

Public Involvement ..................................................................................................................................................11

Scoping ................................................................................................................................................................11

Public Comment Period .......................................................................................................................................12

Consultation.............................................................................................................................................................12

Tribes...................................................................................................................................................................12

State Historic Preservation Office........................................................................................................................12

Endangered Species Act.......................................................................................................................................13

Tiering and Reference..............................................................................................................................................14

Conformance and Consistency with Land Use Plans and Other Decisions..............................................................15

Resource Management Plans on the Northwest Oregon District .......................................................................16

Other BLM Management Plans ...........................................................................................................................17

Chapter 2 - The Alternatives ................................................................................................................................ 18

The No Action Alternative (Alternative 1) ...............................................................................................................18

Alternative 2 (Terrestrial Invasive Plant Management)...........................................................................................20

Alternative 3 (Terrestrial and Aquatic Invasive Plant Management) ......................................................................22

Annual Treatment Plan (Alternatives 2 and 3) ........................................................................................................23

Summary of Invasive Plant Treatments Under Each Alternative.............................................................................24

Alternatives Considered but Eliminated from Detailed Study.................................................................................25

No Herbicides ......................................................................................................................................................25

Use Fewer Herbicides than Analyzed Under the Action Alternatives .................................................................26

Use More Herbicides than Analyzed Under the Action Alternatives...................................................................26

Use Vinegar, Salt, Soap, Sugar, Wood Chips, Essential Oils, Hot Water or Foam, or Other Household Products 

to control Invasive Plants ....................................................................................................................................27

Use Non-Herbicide Methods First, Use Herbicides Only Where Absolutely Necessary and Decrease Their Use in 

the Future ............................................................................................................................................................28

Limit Herbicide Treatments to Early Detection Rapid Response.........................................................................28

Include the Use of Herbicides for Native Vegetation ..........................................................................................28

Reduce Management Activities Implicated in Invasive Plant Spread..................................................................29

Chapter 3 - Affected Environment and Environmental Consequences................................................................. 30

Determination of Effects in this Environmental Analysis ........................................................................................30

Issue 1: How does treatment efficacy under the alternatives affect the spread of invasive plants?......................31

Analytical Assumptions and Methods .................................................................................................................31

Affected Environment .........................................................................................................................................34

Environmental Consequences.............................................................................................................................35

Issue 2: What are the effects to Special Status aquatic species from aquatic invasive plant treatments?.............39

Analytical Methods..............................................................................................................................................39

Affected Environment .........................................................................................................................................40

Treatments Planned Related to the Issue ...........................................................................................................41

Protection Measures ...........................................................................................................................................41
Integrated Invasive Plant Management for the Northwest Oregon District

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Environmental Consequences.............................................................................................................................42

Issue 3: How would the alternatives affect the cost of invasive plant control?......................................................47

Analytical Methods..............................................................................................................................................47

Treatments Planned Related to the Issue ...........................................................................................................48

Environmental Consequences.............................................................................................................................48

Consultation and Coordination............................................................................................................................ 50

List of Preparers.......................................................................................................................................................50

Review Opportunity.................................................................................................................................................50

Glossary ................................................................................................................................................... 51

References ................................................................................................................................................... 61

Tables

Table 1-1. Existing NEPA Analyses Authorizing Invasive Plant Treatments...................................................................5

Table 1-2. Listed Species Documented or Suspected on the Northwest Oregon District ...........................................13

Table 1-3. Endangered Species Act Consultation ........................................................................................................13

Table 2-1. Northwest Oregon District Annual Treatment Summary (2011-2017).......................................................20

Table 2-2. Comparison of the Alternatives, Treatment Methods................................................................................24

Table 3-1. Summary of Factors that Affect the Spread of Invasive Plants...................................................................34

Table 3-2. Acres With No Adequate Control Methods, by Species Group, No Action Alternative..............................37

Table 3-3. Acres With No Adequate Control Methods, by Species Group, Alternative 2............................................38

Table 3-4. Projected Infestation Size Over 15 Years, Aquatic Infestations, Alternative 3 ...........................................39

Table 3-5. Aquatic Federally-Listed and Special Status Species within the Northwest Oregon District......................40

Table 3-6. Forest Service-Evaluated Herbicide Risk Categories for Aquatic Organisms (Aquatic Formulations) ........43

Table 3-7. Summary of Effects (Issue 2) ......................................................................................................................46

Table 3-8. Direct Costs of Invasive Plant Treatments, by Gross Acre ..........................................................................47

Table 3-9. Average Direct Cost of Treatments (Annual)..............................................................................................48

Table 3-10. Costs of Effectively Treated Acre, by Alternative .....................................................................................49

Figures

Figure 3-1. Relationship between Area Occupied by Invasive Plant Species and Time...............................................32

Figure 3-2. Acres of Invasive Plants, 15 year Projection (No Action Alternative)........................................................36

Figure 3-3. Acres of Invasive Plants, 15 year Projection (Alternative 2)......................................................................38

Maps

Map 1-1. Land Administration

Appendices

Table of Contents ........................................................................................................................................................67

Appendix A: Invasive Plants on the District.................................................................................................................72

Appendix B: Integrated Invasive Plant Management..................................................................................................81

Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan ....................................................98

Appendix D: Protection Measures.............................................................................................................................144

Appendix E: Herbicides Formulations and Adjuvants................................................................................................188

Appendix F: Herbicide Risk Assessment Summaries .................................................................................................204

Appendix G: Issues Not Analyzed in Detail................................................................................................................220
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

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Chapter 1 - Purpose and Need

The Northwest Oregon District of the Bureau of Land Management (BLM) manages 714,395 acres in 14 counties –

including all BLM-administered lands in Benton, Clackamas, Clatsop, Columbia, Lincoln, Linn, Marion, Multnomah, 

Polk, Tillamook, Washington, and Yamhill Counties, the majority of BLM-administered lands in Lane County, and a 

small portion of Douglas County (see Map 1-1; maps are located at the end of this printed document or in a 

separate downloadable file, available on the BLM 

ePlanning website). In addition, the Northwest Oregon 

District collaborates with other landowners on efforts to 

control invasive plants across multiple ownerships.

The District is proposing to update its existing integrated 

invasive plant management programs on almost all1 of 

these lands. Until 2016, the BLM managed the Northwest 

Oregon District as two districts – the Salem District, which 

included the Tillamook, Marys Peak, and Cascades Field 

Offices, and the Eugene District, which included the 

Siuslaw and Upper Willamette Field Offices, as well as the 

West Eugene Wetlands. Available invasive plant treatment 

methods have varied by field office, and include manual (e.g., hand-pulling, digging, grubbing, solarization), 

mechanical (e.g., mowing, tilling or disking, string trimmers, propane torch), seeding and planting, prescribed fire, 

biological control agents (generally insects), targeted grazing, and herbicides (primarily glyphosate2

). The Resource 

Management Plan for Northwestern and Coastal Oregon (UDSI 2016d) and the Resource Management Plan for the 

West Eugene Wetlands (USDI 2015b) direct the District to prevent, detect, and rapidly control new invasive plant 

infestations, as well as to use a variety of direct control methods to manage existing infestations. Table 1-1 shows 

the treatment options available in each field office and the National Environmental Policy Act (NEPA) document 

under which those treatments were analyzed.

Table 1-1. Existing NEPA Analyses Authorizing Invasive Plant Treatments

NEPA Analysis Year Field Office / Project 

Area

Invasive Plant Treatments 

Currently AllowedA

This EA and 

Associated 

Decision will: 

Sandy Wild and Scenic River and 

State Scenic Waterway 

Environmental Assessment and 

Management Plan (USDI 1993)

1993 

Decision

Sandy Wild and 

Scenic River Corridor 

(in the Cascades Field 

Office)

Prohibits the use of pesticidesB in 

riparian zones (areas) on federallymanaged landsCModify

Westside Salem Integrated NonNative Plant Management Plan 

Environmental Assessment 

(EA)(USDI 2008d)

2008 

Decision

Tillamook and Marys 

Peak Field OfficesD

Invasive plants: manual, 

mechanical, prescribed fire, grazing, 

competitive plantings, biological 

control agents

Noxious weeds only: glyphosate 

Replace

 1 This EA does not address invasive plant management at the Horning Seed Orchard (Cascades Field Office) and Tyrrell Seed 

Orchard (Siuslaw Field Office). Invasive plant management on these seed orchards is addressed in separate seed orchard 

integrated pest management NEPA analyses. 2 The herbicide active ingredient (e.g., glyphosate) is the part of an herbicide formulation or product (e.g., RoundUp) that 

destroys, repels, desiccates, or otherwise controls the target plant. In this EA, herbicides are referred to by their active 

ingredient name rather than their product names. A full list of current product names that can be used on BLM-managed lands 

can be found in Appendix E.

Invasive plants are non-native aggressive plants with 

either the potential to cause significant damage to 

native ecosystems, cause significant economic losses, 

or both.

Noxious weeds are a subset of invasive plants that are 

State-, or federally-listed as injurious to public health, 

agriculture, recreation, wildlife, or any public or private 

property.

Thus, the term “invasive plants” includes noxious 

weeds in this EA (Oregon FEIS – USDI 2010a).
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

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NEPA Analysis Year Field Office / Project 

Area

Invasive Plant Treatments 

Currently AllowedA

This EA and 

Associated 

Decision will: 

Cascades Resource AreaE Invasive 

Non-Native Plant Management 

EA (USDI 2009)

2009-2018 Cascades Field 

OfficeD, E

Invasive plants: manual, 

mechanical, prescribed fire, grazing, 

competitive plantings, biological 

control agents

Noxious weeds only: glyphosate, 

2,4-D, picloram, dicamba

Replace

Marys Peak Resource AreaE

Noxious Weed Control Utilizing 

Glyphosate EA (USDI 2010c)

2010 

Decision

Marys Peak Field 

OfficeD, E

Noxious weeds only: manual, 

mechanical, prescribed fire, grazing, 

competitive plantings, biological 

control agents, glyphosate

Replace

Proposed Resource Management 

Plan and Final Environmental 

Impact Statement for the Bureau 

of Land Management West 

Eugene WetlandsF Resource 

Management Plan (USDI 2015a)

2015 

Decision G

West Eugene 

Wetlands (in Siuslaw 

Field Office)

Invasive plantsH: prescribed fire, 

seeding, manual, mechanical, 

grazing, glyphosate, triclopyr, 

clopyralid, and research and 

demonstration plots of 

aminopyralid and fluazifop-P-butyl

Tier

Categorical Exclusion for Invasive 

Plant Control: Siuslaw Field Office 

and Upper Willamette Field 

Office, Fiscal Years 2018-2019 

(USDI 2018)

2018 

Decision

Siuslaw and Upper 

Willamette Field 

Offices

Invasive plants: manual and 

mechanical methods and seeding Replace

A. Terrestrial invasive plants. Aquatic invasive plants are not addressed in any existing NEPA analysis.

B. The term “pesticide” covers a wide array of chemicals and substances used to kill, repel, or control certain forms of animal or plant life that 

are considered pests. This includes insecticides, rodenticides, and even disinfectants intended to kill bacteria and viruses, in addition to 

herbicides for plants.

C. Outside of riparian zone, under the No Action Alternative, treatments in the Sandy Wild and Scenic River Corridor would follow the direction 

in Cascades Resource Area Invasive Non-Native Plant Management EA and Decision Record (USDI 2009).

D. Includes the management of invasive plants within Field Office boundaries in cooperation and conjunction with other landowners.

E. BLM Field Offices were formerly referred to as Resource Areas.

F. The West Eugene Wetlands includes 1,340 acres of BLM-administered lands in the Siuslaw Field Office that are primarily managed to 

contribute to the recovery of species listed under the Endangered Species Act.

G. The West Eugene Wetlands Resource Management Plan does not authorize specific projects. On-the-ground actions taken in conformance 

with this Resource Management Plan require additional decision-making.

H. Non-native invasive plants. The West Eugene Wetlands Resource Management Plan and its associated EIS also describes the use of these 

treatment methods on native invasive plants.

The District proposes to update and expand this program by:

• Allowing additional non-native invasive plants that are not listed as noxious weeds to be treated with 

herbicides when necessary;

• Making additional herbicides available for use; and,

• Making all non-native invasive plant treatment options available district-wide.

The proposed action for this project is to provide for an invasive plant management program that allows the use of 

treatment methods district-wide, and to provide for efficient management of invasive plants through the use of 

management tools that are selective, provide effective control, and have few adverse environmental effects. 

Accordingly, the BLM is evaluating the use of additional herbicides that are effective at lower rates, control more

species of invasive plants, decrease the potential for herbicide resistance, and can be used to make associated 

non-herbicide methods more effective (USDI 2010b:19-25). This would better align the program with the principles 

of integrated pest and vegetation management: protecting, maintaining, and restoring ecologically diverse and 

properly functioning native plant communities on public lands (USDI 2008a). This EA is programmatic in nature, 

and as such does not authorize specific projects. Subsequent on-the-ground actions require additional decisionmaking.
Integrated Invasive Plant Management for the Northwest Oregon District

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Chapter 1 – Purpose and Need

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The additional herbicides, and their use on all invasive plants, were addressed in:

• the 2007 Final Programmatic Environmental Impact Statement (2007 PEIS) and Record of Decision for 

Vegetation Treatments Using Herbicides on BLM Lands in 17 Western States (USDI 2007a, b);

• the 2010 Final Environmental Impact Statement (Oregon FEIS) and Record of Decision for Vegetation 

Treatments Using Herbicides on BLM Lands in Oregon (USDI 2010a, b); and,

• the 2016 Final Programmatic Environmental Impact Statement (2016 PEIS) and Record of Decision for 

Vegetation Treatments Using Aminopyralid, Fluroxypyr, and Rimsulfuron (USDI 2016a, b).

Since 1984, the BLM has been under a court injunction, which has limited the use of herbicides on BLMadministered lands in Oregon. The 1984 U.S. District court injunction, amended in 1987, limited the BLM to using 

only four herbicides and restricted their use to noxious weeds only (USDI 2010a:3). The Court amended this 

injunction in 2011 (following completion of the 2010 Oregon FEIS and Record of Decision) permitting the BLM to 

use additional herbicides and to target additional plant species once site-specific NEPA analysis has been 

completed3

. These analyses must be tiered to the Oregon FEIS, the 2007 PEIS, or subsequent analysis at the 

National or State level4

.

The action alternatives in this EA examine the environmental effects of BLM’s proposal to expand and update its 

integrated weed management program at a site-specific scale within the District. This EA and its associated 

decision would replace the Westside Salem Integrated Non-native Plant Management Plan Final Decision and 

Rationale (USDI 2008d), Cascades Area Resource Area Invasive Non-native Plant Management Decision Record

(USDI 2009), the Marys Peak Resource Area Noxious Weed Control Utilizing Glyphosate Final Decision and 

Rationale (USDI 2010d), and the Categorical Exclusion: Siuslaw Field Office and Upper Willamette Field Office

Invasive Plant Control (USDI 2018). This EA will tier to the non-native invasive plant management described in the 

Proposed Resource Management Plan and Final Environmental Impact Statement for the Bureau of Land 

Management West Eugene Wetlands Resource Management Plan (USDI 2015a)5. In addition, the action 

alternatives in this EA would modify the Sandy Wild and Scenic River and State Scenic Waterway Environmental 

Assessment and Management Plan (USDI 1993) to allow the use of herbicides in riparian zones on federallymanaged lands.

This chapter starts with a Need section, followed by a Purposes section, which briefly specifies the underlying 

purpose and need to which the agency is responding with its alternatives (Chapter 2). Following that, an Issues

section presents the issues that will guide the analysis in Chapter 3. The Decision to be Made section presents how 

the District Manager will determine a decision, as well as the scope of that decision. The Public Involvement 

section describes the scoping and public comment periods, and the Consultation section describes specific 

consultation requirements that occur with regards to Tribes, cultural resources, and federally listed species. The 

Tiering and Reference section describes programmatic NEPA analyses that the EA tiers to, as well as reports that 

the EA references. The last section of this chapter, Conformance and Consistency with Land Use Plans and Other 

Decisions, presents other direction that guides the analysis or decision.

The Need

Invasive plants have deleterious impacts on the structure, composition, and function of ecosystems. Adverse 

effects of invasive plants can include resource loss or degradation of ecosystem function, including displacement of 

 3 The 2011 amended injunction also states that BLM shall not aerially spray herbicides west of the Cascade crest and shall not 

spray herbicides for the production of livestock forage or timber production.

4 Such as the 2016 PEIS.

5 The Proposed Resource Management Plan and Final Environmental Impact Statement for the Bureau of Land Management 

West Eugene Wetlands Resource Management Plan tiers to the 2010 Oregon FEIS and analyzes herbicide use on noxious weeds, 

non-native invasive plants, and native invasive plants.
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

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native vegetation; reduction in habitat and forage for wildlife and livestock; loss of federally listed and other 

Special Status6 species’ habitat; increased soil erosion; reduced water quality; reduced soil productivity; and 

reduced wilderness and recreation values (USDI 2010a:7). For example, native short-statured grasses have largely 

been displaced by non-native, aggressively growing grasses across the prairies and savannas of western Oregon

and in aquatic ecosystems, western pond turtles are not likely to inhabit ponds that are heavily infested with 

parrot feather or other aquatic invasive plants that form contiguous mats of vegetation.

Invasive plants infestations are also responsible for economic losses; a 2014 Oregon Department of Agriculture 

(ODA) report estimates that 25 of the most problematic noxious weeds listed in Oregon7 cost the State an 

estimated 83.5 million dollars per year (ODA 2014). While much of this loss is to agricultural areas, invasive plants 

on BLM-administered lands may spread to adjacent non-BLM-administered lands, increasing control costs for 

affected landowners and degrading land values.

In addition, there are invasive plants on neighboring (non-BLM-administered) lands that may spread to BLMadministered lands at any time. The BLM participates in cooperative invasive plant control efforts with other 

private and government entities such as the ODA, Cooperative Weed Management Associations, the Nature 

Conservancy, Western Invasives Network, watershed councils, and others. However, the BLM’s current inability to 

use herbicides commonly used by cooperators on adjacent lands results in less effective control, coordination 

challenges, or both.

Species of terrestrial and aquatic invasive plants on the District have been mapped on over 17,000 acres in over 

49,000 separate known locations8

, with individual locations ranging from a few plants to a 366-acre site of Scotch 

broom (Cytisus scoparius). In addition, there are thousands of acres of unmapped invasive plants known on the 

District; for example, tansy ragwort (Senecio jacobaea), is estimated to occupy over 2,000 acres (see the Existing 

Invasive Plant Sites section in Appendix B). Despite the efforts of the existing invasive plant program, these species 

are continuing to spread at an estimated rate of 12 percent per year (see the Spread from Existing Plant Sites

section in Appendix B) (USDI 2010a:133).

For some noxious weed species such as Japanese, Bohemian, and giant knotweeds (Polygonum spp.), neither nonherbicide methods nor the herbicides currently available on the District result in adequate control9

. The existing 

program, which (with the exception of the West Eugene Wetlands) only allows herbicides treatments of noxious 

weeds, also does not have an adequate method for selectively10 controlling other invasive plants that are not listed 

as noxious weeds such as English holly (Ilex aquifolium) and periwinkle species (Vinca spp.). In addition, outside of 

the West Eugene Wetlands, the Siuslaw and Upper Willamette Field Offices do not currently have the approval to 

use herbicides and rely on mechanical and manual methods to treat invasive plants.

Herbicides that are more selective than the currently approved options are available to treat invasive plants. These 

herbicides generally can be used in lower quantities and pose less environmental and human health safety risk11

than the herbicides the BLM is currently authorized to use (USDI 2010a:80 and others). Furthermore, if these 

 6 Federally listed threatened, endangered, proposed, or candidate species, and species managed as Bureau Sensitive species by 

the BLM.

7 The latest ODA noxious weed list includes a total of 132 noxious weed species (ODA 2017).

8 Summarized in Appendix A.

9 As described further in Appendix C, Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan, lack of adequate 

control means that control methods are unavailable or unfeasible and treatments would not be attempted even in high priority 

circumstances.

10 Non-selective herbicides can be used to treat any plant species; however, that can make it difficult to target an invasive plant 

species growing among desirable species. Selective herbicides control specific plant species, while leaving neighboring desired 

plant species unharmed.

11 Risk is defined as the likelihood that an adverse effect (such as skin or eye irritation, leaf damage, mortality, etc.) may result 

from a specific set of circumstances.
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

9

additional herbicides were approved, it is estimated that the efficacy of BLM’s invasive plant treatment would 

improve from an estimated 30 to 60 percent under the No Action Alternative to 80 percent12 under the action 

alternatives (USDI 2010a:136).

The Resource Management Plans for the District direct the District to prevent, detect, and rapidly control new 

invasive plant infestations, as well as to use a variety of direct control methods to manage existing infestations 

(USDI 2016d:80, 2015a:29-30). Executive Order 13112 (February 1999, as amended in December 2016) requires 

Federal agencies to “(i) prevent the introduction of invasive species; (ii) detect and respond rapidly to and control 

populations of such species in a cost-effective and environmentally sound manner; (iii) monitor invasive species 

populations accurately and reliably; [and] (iv) provide for restoration of native species and habitat conditions in 

ecosystems that have been invaded...”

All of the foregoing factors indicate that there is a need for a more effective invasive plant control program.

The Purposes

The District proposes to update its existing invasive plant management program to:

• Provide a range of direct control methods that allow individual treatments in varying conditions to have 

more effective control of invasive plants, in accordance with the Records of Decision for the Northwest 

Area Noxious Weed Control Program Final Environmental Impact Statement (USDI 1987b) and the 

Vegetation Treatments Using Herbicides on Bureau of Land Management Lands in Oregon Environmental 

Impact Statement (USDI 2010b), so resource and economic losses from invasive plants are reduced.

In addition, this EA is consistent in scope with the Oregon FEIS (to which this EA tiers), which includes a purpose to:

• Prevent treatments from having unacceptable adverse effects to applicators and the public, to desirable 

flora and fauna, and to soil, air, and water.

Issues

In the context of an environmental analysis, an issue is defined as a point of disagreement, debate, or dispute with 

a proposed action based on some anticipated environmental effect. For the purposes of BLM’s NEPA analyses, an 

issue:

• has a cause and effect relationship with the proposed action or alternatives;

• is within the scope of the analysis;

• has not been decided by law, regulation, or previous decision; and

• is amenable to scientific analysis rather than conjecture (USDI 2008c).

Issues Analyzed in Detail

The issues identified during internal (BLM) and external (public) scoping were used to guide the effects analysis in 

Chapter 3. Issues are analyzed in detail when:

a) the issue is related to how the alternatives respond to the purpose and need; or,

b) analysis is necessary to determine the significance of impacts.

 12 Treatments are not 100 percent effective at controlling all treated populations. Under any alternative, some level of 

retreatment may be necessary to achieve complete control. Treatments would be monitored, and a portion of the acres might 

require retreatment. The amount of retreatment necessary depends upon the extent to which the first treatment controls the 

target weed. More information about treatment effectiveness can be found in Issue 1 (see Chapter 3).
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

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The following issues are analyzed in detail in Chapter 3:

• Issue 1: How does treatment efficacy under the alternatives affect the spread of invasive plants?

• Issue 2: What are the effects to Special Status aquatic species from aquatic invasive plant treatments?

• Issue 3: How would the alternatives affect the cost of invasive plant control?

Issues Not Analyzed in Detail

Several issues identified during internal and external scoping were considered but not analyzed in detail in this EA. 

Issue are not analyzed in detail when:

• the issue does not respond to the purpose and need;

• there is no potential for significant effects13 related to the issue; or,

• the issue has already been appropriately analyzed in documents to which this EA tiers.

Further information about the following issues is included in Appendix G, Issues Not Analyzed in Detail.

• Issue 4 (Native Vegetation): What are the effects of invasive plant treatments on desirable plant 

communities and Special Status plants?

• Issue 5 (Fungi): How would invasive plant treatments affect fungi?

• Issue 6 (Wildlife): How would integrated invasive plant management affect wildlife of conservation 

concern?

• Issue 7 (Birds): How would treatments affect birds that may use potential treatment areas, especially 

during the nesting season?

• Issue 8 (Pollinators): How would herbicide treatments affect pollinators, especially Special Status 

pollinator species?

• Issue 9 (Turtles): How would the treatment of aquatic invasive plants affect the western pond turtle 

and painted turtle?

• Issue 10 (Fish and Aquatic Organisms): What are the effects of terrestrial herbicide treatments along 

streams to fish and aquatic organisms?

• Issue 11 (Human Health): What are the effects to human health from incidentally coming into contact 

with herbicides used on BLM-administered lands?

• Issue 12 (Human Health): What are the hazards to workers treating invasive plants?

• Issue 13 (Human Health): What are effects to human health of mixing two or more herbicides? What 

are the effects from adjuvants and other ingredients mixed with herbicides? What are the effects 

from the degradates when herbicides break down?

• Issue 14 (Human Health): What are effects to human health of using glyphosate, which a California 

court recently found to be cancer-causing, the International Agency for Research on Cancer (IARC) 

has declared a cancer hazard, and has been found in breakfast cereal?

• Issue 15 (Human Health): What are the effects to human health from invasive plants (allergies, 

rashes, etc.)?

• Issue 16 (Soil): How do herbicides detrimentally affect soils?

• Issue 17 (Water): How do herbicides treating terrestrial weeds affect water quality, including ground 

and surface water used for domestic and municipal supply?

• Issue 18 (Water): How do herbicide treatments of aquatic invasive plants affect water quality?

• Issue 19 (Air): How would the alternatives affect air quality?

• Issue 20 (Air): How would the alternatives affect climate change, including greenhouse gas emissions 

and carbon storage?

 13 Effects described in this EA are predicated on application of Protection Measures (see Appendix D).
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

11

• Issue 21 (Traditional and Cultural Uses): How would the treatment of invasive plants affect plant 

resources used by Native Americans given that these plants (or their locations) may not be known by 

the BLM?

• Issue 22 (Environmental Justice): How would the use of herbicides affect minorities and low-income 

populations?

• Issue 23 (Socioeconomics): What are the impacts to local timber production, forest products, 

agriculture, and recreation economies from the management of invasive plants in the Northwest 

Oregon District?

• Issue 24 (Socioeconomics): What is the potential for herbicide contamination of yards, gardens, 

organic farms, vineyards, and bee hives on private lands?

• Issue 25 (Recreation): How will invasive plant management affect the management and use of 

recreation sites?

• Issue 26 (Recreation): What are the effects of herbicides on dogs, horses, and other pets that 

accompany recreationists?

• Issue 27 (Wilderness / Wilderness Study Areas): How will invasive plant management affect 

Wilderness or Wilderness Study Areas on the District?

• Issue 28 (Visual): Would the use of invasive plant treatments affect the visual quality of the 

landscape?

Decision to Be Made

The decision of which alternative to select or whether to modify an alternative based on environmental analysis 

and any other factors identified during public review of this EA and unsigned Finding of No Significant Impact will 

be made by the District Manager for the Northwest Oregon District. The decision-maker will make the decision 

based on the analysis of the issues and how well the alternatives respond to the purpose and need. The decisionmaker will also decide whether the analysis reveals a likelihood of significant adverse effects from the selected 

alternative that cannot be mitigated or that were not already revealed in one or more of the Environmental Impact 

Statements that this EA tiers to. The decision would apply to all invasive plant control activities conducted by BLM 

personnel, contractors, grant holders, lessees, or cooperators, on all lands within the Northwest Oregon District 

(the “District”) except the Horning and Tyrrell Seed Orchards, including BLM-administered lands and other land 

ownerships where the BLM partners on invasive plant control. This EA is programmatic in nature, and as such, a 

Decision would not authorize specific projects. Subsequent on-the-ground actions, including implementation of 

BLM’s 2019 Annual Treatment Plan, would require additional decision-making. The BLM is in the process of 

preparing biological assessments for consultation with the U.S. Fish and Wildlife Service and National Marine 

Fisheries Service. 

Public Involvement

Scoping

Scoping is the process by which the BLM solicits internal and external input on the issues, impacts, and potential 

alternatives that will be addressed as well as the extent to which those issues and impacts will be analyzed in the 

NEPA analysis. Scoping comments, along with other pertinent information, were used to help develop the 

purposes, issues, and alternatives in this EA.

External scoping for the EA was originally conducted in July 2011, with letters sent to interested publics, and 50 

scoping responses were received. The majority of these commenters expressed concern with the use of herbicides.

Due to the lag in time since initiation of scoping and changes to the proposed action, scoping was reopened from 
Integrated Invasive Plant Management for the Northwest Oregon District

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January 5, 2018, through February 8, 2018. Letters were sent to approximately 680 individuals, agencies, and 

organizations and posted on the BLM’s ePlanning website. Fourteen comment letters were received in 2018, 

roughly split between those supportive of the judicious use of herbicides to control invasive plants, those who 

encouraged a cautionary or conservative approach to herbicide use, and those opposed to any alternative that 

includes herbicides. Two commenters were under the misunderstanding that aerial spraying of herbicides was part 

of the proposal. Those who expressed concerns almost exclusively focused on the use of herbicides, suggesting 

reducing or eliminating all use, and instead relying on manual and mechanical methods of control or changing land 

management practices. Requests were made to address the effects of herbicides on human health and unintended 

effects of herbicide drift or overspray on neighboring private land uses, soil, water, air, and wildlife. Some cited 

personal experience with the effects of herbicides used for agriculture or timber production and said that the cost 

of invasive plant control was greater than the resulting benefits. Similar issues were raised during the 2011 

scoping, with additional suggestions to use a decision-making process with clearly defined metrics to prioritize the 

treatment method with the least risk. Many commenters had suggestions for specific treatment methods, such as 

targeted grazing and manual or mechanical treatments with volunteer labor.

Public Comment Period

This EA will be made available for a 30-day public comment period (November 2018) on BLM’s ePlanning site and 

interested members of the public will be notified of the availability of the EA for review. This mailing list is 

contained in the project record file.

Consultation

Tribes

Tribal consultation was initiated in June 2011 with letters to the Confederated Tribes of the Grand Ronde 

Community of Oregon, the Confederated Tribes of the Warm Springs, the Confederated Tribes of Siletz Indians of 

Oregon, and the Confederated Tribes of Coos, Lower Umpqua, and Siuslaw. The letters described the proposed EA, 

announced that scoping would begin, and encouraged the Tribes to enter into government-to-government 

consultation. Following a delay in the preparation of this EA, the same Tribes were contacted with letters in 

January 2018. The letters described the purpose and need and the alternatives and encouraged the Tribes to enter 

into government-to-government consultation and be involved with the process. Staff-to-staff coordination with 

both the Confederated Tribes of Siletz Indians and the Confederated Tribes of the Grand Ronde Community of 

Oregon identified points for future involvement and continued coordination to address areas and plants of 

concern prior to implementation of the Annual Treatment Plans.

State Historic Preservation Office

As part of BLM’s requirements under Section 106 of the National Historic Preservation Act and its implementing 

regulations found at 36 CFR 800 (as amended), consultation with the State Historic Preservation Office (SHPO) 

would be conducted on the District’s Annual Treatment Plans prior to implementing any treatments that have the 

potential to adversely affect cultural resources.

The BLM will follow the 2015 State Protocol between the Oregon BLM and the Oregon SHPO regarding the manner 

in which the Bureau of Land Management meets its responsibilities under the National Historic Preservation Act 

and the National Programmatic Agreement among the BLM, the Advisory Council on Historic Preservation, and the 

National Conference of State Historic Preservation Officers (Oregon SHPO and USDI 2015). As part of the Annual 

Treatment Plan review (see Chapter 2), a cultural resource specialist would review each treatment application 
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

13

(project) to determine whether fieldwork is required to identify cultural resources, and if additional protection 

measures would be needed.

Endangered Species Act

The District has 17 federally listed species that are known or have potential to occur (see Table 1-2)14.

Table 1-2. Listed Species Documented or Suspected on the Northwest Oregon District

Taxon Common Name Scientific Name Population Status Documented 

or Suspected

Plant Willamette Valley daisy Erigeron decumbens var. 

decumbens Endangered Documented

Plant Bradshaw’s lomatium Lomatium bradshawii Endangered Documented

Plant Kincaid’s lupine Lupinus oreganus Threatened Documented

Plant Nelson’s checkermallow Sidalcea nelsoniana Threatened Documented

Plant golden paintbrush Castilleja levisecta Threatened Suspected

Plant water howellia Howellia aquatilis Threatened Suspected

Anadromous 

Fish Coho salmon Oncorhynchus kisutch Oregon Coast, Lower Columbia River Threatened Documented

Anadromous 

Fish steelhead Oncorhynchus mykiss Upper Willamette River, Lower Columbia River Threatened Documented

Anadromous 

Fish Chinook salmon Oncorhynchus tshawytscha Upper Willamette River, Lower Columbia River Threatened Documented

Anadromous 

Fish Pacific eulachon Thaleichthys pacificus Southern Threatened Suspected

Resident Fish bull trout Salvelinus confluentus All Threatened Documented

Insect Fender’s blue butterfly Plebejus icarioides fenderi Endangered Documented

Insect Taylor’s checkerspot 

butterfly Euphydryas editha taylori Endangered Suspected

Insect Oregon silverspot 

butterfly Speyeria zerene hippolyta Threatened Suspected

Bird streaked horned lark Eremophila alpestris strigata Threatened Documented

Bird northern spotted owl Strix occidentalis caurina Threatened Documented

Bird marbled murrelet Brachyramphus marmoratus Threatened Documented

Formal and informal consultation that covers herbicides and other invasive plant treatments on the District has 

occurred with the U.S. Fish and Wildlife Service (FWS) and National Marine Fisheries Service (NMFS) on numerous 

occasions (see Table 1-3). The BLM submits annual reports to the Services in compliance with these consultations 

at both the State- and District-level.

Table 1-3. Endangered Species Act Consultation

Program / Biological Assessment Agency / Area Year Consultation

Vegetation Treatments Using Herbicides on BLM Lands 

in 17 Western States PEIS (USDI 2007a)

Vegetation Treatments on BLM Lands in 17 Western 

States Programmatic Environmental Report (USDI 

2007d)

Vegetation Treatments on BLM Lands in 17 Western 

States Biological Assessment (USDI 2007c)

BLM - 17 

Western States 2007

FWS Letter of Concurrence

(Reference: FWS/AES/DCHRS/027171)

NMFS Biological Opinion

(Tracking Number: FPR-2004-1502)

 14 More information about the effects to these species can be found in Chapter 3 or Appendix G, including Issue 3 (federally 

listed plants), Issues 2 and 10 (federally listed fish), Issue 7 (federally listed birds), and Issue 9 (federally listed butterflies).
Integrated Invasive Plant Management for the Northwest Oregon District

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Program / Biological Assessment Agency / Area Year Consultation

Vegetation Treatments Using Herbicides on BLM Lands 

in Oregon (USDI 2010a)

Vegetation Treatments on BLM Lands in 17 Western 

States Biological Assessment (USDI 2007c)

BLM - Oregon 2010

FWS Letter of Concurrence

(TAILS Number: 13420-2010-I-0173)

NMFS Biological Opinion

(Number: 2009 / 05539)

Aquatic Restoration Biological Assessment II (USDA et al. 

2013)

BLM and Forest 

Service - OR, 

WA, parts of CA, 

NV, and ID

2013

Aquatic Restoration Biological Opinion (ARBO 

II)

(NMFS Tracking Number: NWP-2013-9664)

(FWS Reference: 01EOFW00-2013-F-0090)

Biological Assessment for the Resource Management 

Plan for the West Eugene Wetlands in Lane County, 

Oregon on the US BLM – Eugene District (USDI 2014a)

BLM - West 

Eugene 

Wetlands

2014 Biological Opinion (FWS)

(Reference: 01EOFW00-2014-F-0139)

Biological Assessment (USDI 2016c) for Vegetation 

Treatments Using Aminopyralid, Fluroxypyr, and 

Rimsulfuron PEIS (USDI 2016a)

BLM - 17 

Western States

2015 / 

2016

FWS Letter of Concurrence

(Reference: FWS/AES/DER/BCH/061446)

NMFS Biological Opinion

(Tracking Number: PCTS FPR-2015-9121)

Consultation resulted in Conservation Measures and Project Design Criteria identified to protect District-listed 

species from treatments, which are listed in Appendix D, in the Protection Measures section.

In addition, the BLM is in the process of preparing Biological Assessments. The BLM will consult with the National 

Marine Fisheries Service to address:

• The use of fluazifop-P-butyl at distances up to 300 feet from listed anadromous fish habitat 

(Alternatives 2 and 3)

• Treatments of aquatic invasive plant infestations in waterbodies that contain federally threatened or 

endangered anadromous fish species or provide critical habitat (Alternative 3)

The BLM will consult with the U.S. Fish and Wildlife Service to address:

• The use of fluazifop-P-butyl, rimsulfuron, fluroxypyr, and hexazinone in listed species habitat

(Alternatives 2 and 3)

• Treatments of terrestrial invasive plant infestations in Taylor’s checkerspot butterfly, Fender’s blue 

butterfly, and streaked horned lark critical habitat (Alternatives 2 and 3)

• Treatments of terrestrial invasive plant infestations in federally threatened or endangered plant 

habitats (Alternatives 2 and 3)

The BLM will adopt any additional protection measures that result from consultation with either agency.

Tiering and Reference

Tiering refers to the coverage of general matters in broader environmental impact statements with subsequent 

narrower statements or other environmental analyses. Tiering allows agencies to narrow the range of alternatives, 

narrow the scope of analysis, and reach a Finding of No Significant Impact for an action that may have significant 

impacts15. This allows incorporation by reference of the general discussions so as to concentrate solely on the 

issues specific to the statement subsequently prepared (40 CFR 1508.28).

For its analysis of herbicide effects, this EA tiers to three environmental impact statements (EISs), all completed at 

the State or National level. This EA tiers to the 2007 PEIS for Vegetation Treatments Using Herbicides on BLM Lands 

in 17 Western States (USDI 2007a) for the use of chlorsulfuron (west of the Cascades). In addition, this EA tiers to 

the 2016 PEIS for Vegetation Treatments Using Aminopyralid, Fluroxypyr, and Rimsulfuron (USDI 2016a), for the 

 15 The BLM NEPA Handbook (USDI 2008c) states that an EA may be prepared for an action with significant effects if that EA is 

tiered to a broader environmental impact statement, which fully analyzed those significant effects.
Integrated Invasive Plant Management for the Northwest Oregon District

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use of those three herbicides. For the remaining herbicides analyzed in this EA, this EA tiers to the 2010 Final 

Environmental Impact Statement for Vegetation Treatments Using Herbicides on BLM Lands in Oregon (Oregon 

FEIS, USDI 2010a). The 2010 Record of Decision for the Oregon FEIS (USDI 2010b) requires, with few specific 

exceptions16, the preparation of new site-specific analyses before herbicides other than 2,4-D, dicamba, 

glyphosate, or picloram can be used and these analyses must be tiered to the Oregon FEIS (USDI 2010b:9). This EA 

provides the site-specific analysis for the District. The alternatives (including the No Action Alternative) must 

adhere to restrictions described in the three EISs (USDI 2010b:30) including:

• Mitigation Measures17 from the 2007 PEIS Record of Decision, 2010 Oregon FEIS Record of Decision, and 

2016 PEIS Record of Decision.

• Standard Operating Procedures from the 2007 PEIS.

• Conservation Measures for Special Status species from the 2007 and 2016 PEISs’ Biological Assessments.

• Typical and maximum herbicide application rates analyzed in the 2007 PEIS, 2010 Oregon FEIS, and 2016 

PEIS.

Mitigation Measures, Standard Operating Procedures, and Conservation Measures adopted with the Records of 

Decisions for these three EISs (USDI 2007b, 2010b, and 2016b) are included in Appendix D of this EA. Actions in this 

EA are designed to be consistent with the actions authorized in the Records of Decisions for these three EISs (USDI 

2007b, 2010b, and 2016b).

For its analysis of non-herbicide treatments, this EA tiers to the Northwest Area Noxious Weed Control Program 

Final EIS and Supplement (USDI 1985, 1987a) and is consistent with the actions authorized in its Record of Decision

(USDI 1987b). This EA also incorporates by reference elements of the 2007 Vegetation Treatments on BLM Lands in 

17 Western States Programmatic Environmental Report, which describes the integrated vegetation management 

program and discloses the general effects associated with non-herbicide control methods (USDI 2007d).

In addition, Issue 1 in Chapter 3 and Issues 4, 7, 8, and 21 in Appendix G tier to the analyses in the Proposed 

Resource Management Plan and Final Environmental Impact Statement for Resource Management Plans for 

Western Oregon (USDI 2016e) or the Proposed Resource Management Plan and Final Environmental Impact 

Statement for the Bureau of Land Management West Eugene Wetlands Resource Management Plan (USDI 2015a).

Conformance and Consistency with Land Use Plans 

and Other Decisions

The BLM’s integrated invasive plant management program is the product of decades of laws, Executive orders, and 

BLM and Department of the Interior policies and direction. Several Federal laws direct the BLM to aggressively 

manage invasive plants and other vegetation to improve ecosystem health. Section 302(b) of the Federal Land 

Policy and Management Act of 1976 directs BLM to “take any action necessary to prevent unnecessary or undue 

degradation of the lands” (43 U.S.C. § 1732(b)(2)). Executive Order 13112 (February 1999, as amended December 

5, 2016) requires Federal agencies to “(i) prevent the introduction of invasive species; (ii) detect and respond 

rapidly to and control populations of such species in a cost-effective and environmentally sound manner; (iii) 

monitor invasive species populations accurately and reliably; [and] (iv) provide for restoration of native species and 

habitat conditions in ecosystems that have been invaded...” In particular, the Carlson-Foley Act of 1968 (43 U.S.C. 

§§ 1241-1243), the Plant Protection Act of 2000 (7 U.S.C. § 7702) and the Noxious Weed Control and Eradication 

Act of 2004 (7 U.S.C. § 7781) authorize the BLM to manage noxious weeds and to coordinate with other Federal 

and State agencies in activities to eradicate, suppress, control, prevent, or retard the spread of any noxious weeds 

 16 Exceptions include NEPA analyses done for the Tyrrell and Horning seed orchards (on the Northwest Oregon District), the 

Provolt and Sprague seed orchards (on the Medford District) and an EA for Sudden Oak Death on the Coos Bay District (USDI 

2010b:30).

17 Mitigation Measures are practices or limitations adopted to mitigate potential adverse effects identified in the 2007 and 2016 

PEISs and Oregon FEIS analyses.
Integrated Invasive Plant Management for the Northwest Oregon District

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on federally-managed lands. The Federal Noxious Weed Act of 1974 (7 U.S.C. § 2814(a)) established a program to 

manage undesirable plants, implemented cooperative agreements with State agencies, and established integrated 

management systems to control undesirable plant species.

Resource Management Plans on the Northwest Oregon 

District

The Federal Land Policy and Management Act (1976) requires that all management decisions be consistent with 

the approved land use plan (43 CFR 1610.5-3). Management activities on the District are covered by two Resource 

Management Plans: the Northwestern and Coastal Oregon Resource Management Plan and Record of Decision

(USDI 2016d) and the West Eugene Wetlands Resource Management Plan and Record of Decision (USDI 2015b).

The Resource Management Plan for Northwestern and Coastal Oregon (UDSI 2016d:80) directs the District to:

• Implement measures to prevent, detect, and rapidly control new invasive plant infestations.

• Use manual, mechanical, herbicides, and biological treatments to manage invasive plant infestations.

The Resource Management Plan for the West Eugene Wetlands (USDI 2015b:24-25) directs the agency to:

• In the Prairie Restoration Area, apply herbicides for vegetation control where prescribed burning, manual, 

mechanical, and other non-chemical vegetation treatments do not provide sufficient vegetation control 

for restoration and maintenance of high quality habitat for prairie-related species. Herbicides may be 

used for control of noxious weeds and invasive non-native plants. Follow Protection Measures for 

herbicide applications (see Appendix D).

• In the Natural Maintenance Area, apply herbicides for vegetation control where prescribed burning, 

manual, mechanical, and other non-chemical vegetation treatments do not provide sufficient vegetation 

control for maintenance and enhancement of existing plant and animal habitats. Herbicides may be used 

for control of noxious weeds and invasive non-native plants to achieve habitat goals identified as part of 

recovery or delisting or for conservation management of Special Status species. Follow Protection 

Measures for herbicide application (see Appendix D).

Northwestern and Coastal Oregon Resource Management Plan

The Northwestern and Coastal Oregon Resource Management Plan provides management direction and objectives 

for the management of all resources on BLM-administered lands in the Northwest Oregon District, Coos Bay 

District, and the Swiftwater Field Office of the Roseburg District. The actions proposed in this EA are in 

conformance with the management direction of this Resource Management Plan. Management objectives and 

direction related to invasive plant management are included in the Invasive Species (USDI 2016d:80) section of the 

Resource Management Plan. Additional management objectives and direction applicable to the program can be 

found in the Land Use Allocations – Congressionally Reserved Lands and National Conservation Lands (USDI 

2016d:55-56), District-Designated Reserve – Areas of Critical Environmental Concern (USDI 2016d:57), DistrictDesignated Reserve – Lands Managed for their Wilderness Characteristics (USDI 2016d:58), Riparian Reserves (USDI 

2016d:68), Hydrology (USDI 2016d:79), Rare Plants and Fungi (USDI 2016d:86), Soil Resources (USDI 2016d:89-90),

Visual Resources Management (USDI 2016d:93-94), and Wildlife (USDI 2016d:95) sections.

West Eugene Wetlands Resource Management Plan

The West Eugene Wetlands includes 1,340 acres of BLM-administered lands in the Siuslaw Field Office that are 

primarily managed to contribute to the recovery of species listed under the Endangered Species Act. The actions 

proposed in this EA are in conformance with the management direction of this Resource Management Plan. This 

EA tiers to the Proposed Resource Management Plan and Final Environmental Impact Statement for the Bureau of 
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Chapter 1 – Purpose and Need

17

Land Management West Eugene Wetlands Resource Management Plan (USDI 2015a) and the action alternatives 

make additional herbicides available for use for non-native invasive plants in the West Eugene Wetlands (see 

Chapter 3 and Appendix G). This EA and associated decision will not change, amend, replace, or otherwise modify 

the management of native invasive plants described in the Resource Management Plan and associated EIS. The 

BLM-administered lands within the West Eugene Wetlands planning area are assigned to the following two land 

use allocations - Prairie Restoration Areas or Natural Maintenance Areas. Herbicide use in these areas is directed 

for management of noxious weeds, native invasive plants, and non-native invasive plants, allowing for habitat 

restoration, maintenance, and enhancement. Herbicide use on invasive native plants is directed to achieve habitat 

goals identified as part of recovery or delisting or for conservation management of Special Status species as 

identified in the species Recovery Plan. The 2015 Resource Management Plan EIS tiers to the 2010 Oregon FEIS for 

its use of herbicides. Management objectives and direction related to invasive plant management are included in 

the Prairie Restoration Area (USDI 2015b:24), Natural Maintenance Area (USDI 2015b:24-25), and Plants (USDI 

2015b:24) sections of the Resource Management Plan.

Other BLM Management Plans

While there are additional management plans on the District, the invasive plant management EAs and Categorical 

Exclusion shown in Table 1-1, the above-described Resource Management Plans, and the Sandy Wild and Scenic 

River and State Scenic Waterway Management Plan are the only plans that specifically address or constrain the 

invasive plant management program on the District.

Sandy Wild and Scenic River and State Scenic Waterway Management Plan

The Sandy Wild and Scenic River and State Scenic Waterway Management Plan (USDI 1993) is a framework for 

cooperative management of the 12.5 mile section of the Sandy River from Dodge Park to Dabney State Park. This 

section of the river includes 3.8 miles that are classified as a Scenic River and 8.7 miles that are classified as a 

Recreational River. The BLM and the Oregon State Parks and Recreation Department worked together to develop 

this plan. The plan prohibits the use of pesticides18 in riparian zones on federally-managed lands. (No specific 

invasive plant direction is described in the plan.) The action alternatives in this EA propose modifying this 

management plan to authorize the use of herbicides on federally-managed lands in riparian zones, allowing for 

effective treatment of invasive riparian plants (such as knotweed species). (The action alternatives do not propose 

to change the restriction against pesticides that are not herbicides in these riparian zones; other pesticide use 

would still be prohibited.)

 18 The term “pesticide” covers a wide array of chemicals and substances used to kill, repel, or control certain forms of animal or 

plant life that are considered pests. This includes insecticides, rodenticides, and even disinfectants intended to kill bacteria and 

viruses, in addition to herbicides for plants. 
Integrated Invasive Plant Management for the Northwest Oregon District

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Chapter 2 – Integrated Invasive Plant Management and the Alternatives

18

Chapter 2 - The Alternatives

This chapter describes three alternatives in detail; the No Action Alternative, Alternative 2 (Terrestrial Invasive 

Plant Management), and Alternative 3 (Terrestrial and Aquatic Invasive Plant Management). These are the 

alternatives addressed in the effects analysis in Chapter 3. This section also describes the other alternatives that 

the District considered but did not carry forward for detailed study. The alternatives address the dynamic nature of 

invasive plants, including increasing numbers of invasive plant species and changing conditions of infestations. Due 

to the rapid growth and abundance of invasive plants, the size of the land base involved, and the nature of 

multiple uses that take place on it, invasive plant control will remain an ongoing need. The District’s intent is to 

manage invasive plants in order to minimize adverse ecological and economic effects. Table 2-2, Comparison of the 

Alternatives, Treatment Methods shows a comparison of the treatment methods used under each alternative.

The 2010 Oregon FEIS, to which this document tiers, considered three action alternatives, as well as a reference 

analysis which described the effects of not using herbicides on BLM-administered lands. The action alternatives in 

this EA are most similar to Alternative 3 in the Oregon FEIS. The 2007 PEIS, to which this EA and the Oregon FEIS 

tiers, considered four action alternatives. In addition, both of these EISs considered numerous alternatives not 

analyzed in detail. The 2016 PEIS, to which this EA also tiers, considered three additional action alternatives.

None of the alternatives in this EA address invasive plant management on the Horning Seed Orchard (Cascades 

Field Office) or Tyrrell Seed Orchard (Siuslaw Field Office); invasive plant management in these areas is addressed 

in separate integrated pest management analyses for these seed orchards.

Further information about the specific invasive plants on the District and the locations of these plants can be found 

in Appendix A, Invasive Plants on the District and Appendix C, Treatment Key, Invasive Plant Sites, and the Annual 

Treatment Plan. Further information about specific treatment methods can be found in Appendix B, Integrated 

Invasive Plant Management and Appendix C, Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan.

As described in Appendix B, monitoring, including implementation and effectiveness monitoring, is required under 

all alternatives. Effectiveness monitoring would inform adaptive management, including if and how follow-up 

treatments would occur.

The No Action Alternative (Alternative 1)

Under the No Action Alternative, the District would continue to implement the terrestrial invasive plant 

treatments allowed in different field offices or areas, consistent with the Westside Salem Integrated Non-Native 

Plant Management Plan EA and Decision Record (USDI 2008d), Cascades Resource Area Invasive Non-Native Plant 

Management EA and Decision Record (USDI 2009) 19, Marys Peak Resource Area Noxious Weed Control Utilizing 

Glyphosate EA and Decision Record (USDI 2010c), Proposed Resource Management Plan and Final Environmental 

Impact Statement for the Bureau of Land Management West Eugene Wetlands Resource Management Plan (USDI 

2015a) and Record of Decision (USDI 2015b)20, and the Siuslaw Field Office and Upper Willamette Field Office 

Invasive Plant Control Categorical Exclusion (completed every one to two years), Resource Management Plans, and 

other District direction. In the Sandy Wild and Scenic River corridor, the management plan would prohibit the use 

 19 The Cascades Resource Area Invasive Non-Native Plant Management Environmental Assessment analyzes the existing 

program for Cascades Field Office. Though the EA specifies that the analysis “will be effective from February 25, 2009 –

December 31, 2018,” (USDI 2009:5) it is assumed that the program would continue to be implemented after December 31, 

2018 for the purposes of analysis. Invasive plant management is a high priority for the region and for the BLM; it would be 

unrealistic to assume that the Field Office would no longer have any invasive plant control program at all.

20 The West Eugene Wetlands Resource Management Plan does not authorize specific projects. On-the-ground actions taken in 

conformance with this Resource Management Plan require additional decision-making.
Integrated Invasive Plant Management for the Northwest Oregon District

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Chapter 2 – Integrated Invasive Plant Management and the Alternatives

19

of herbicides in riparian zones on federally-managed lands. (Treatments in this corridor would otherwise follow the 

direction in Cascades Resource Area Invasive Non-Native Plant Management EA and Decision Record (USDI 2009).)

Available treatment methods for the Cascades, Marys Peak, and Tillamook Field Offices include manual and 

mechanical methods, targeted grazing, biological control agents, prescribed fire, and competitive seeding and 

planting to treat invasive plants. The herbicides available for noxious weed management efforts would be 2,4-D, 

dicamba, glyphosate, and picloram in the Cascades Field Office, and glyphosate in the Marys Peak and Tillamook 

Field Offices. The Siuslaw and Upper Willamette Field Offices would be limited to manual and mechanical methods

and seeding21. The BLM would continue to treat invasive plants in the West Eugene Wetlands with a variety of 

methods, including prescribed fire, seeding, manual and mechanical methods, solarization, targeted grazing, and 

herbicides including glyphosate, triclopyr, and clopyralid, and research and demonstration22 plots of aminopyralid 

and fluazifop-P-butyl (a maximum of 15 acres unless herbicide Risk Assessments and additional NEPA analyses are

completed). Table 2-2, Comparison of the Alternatives, Treatment Methods, indicates what treatment methods are 

available, area by area.

As described in the existing invasive plant NEPA analyses for the Cascades, Marys Peak, and Tillamook Field Offices, 

the BLM supports and implements cooperative invasive plant treatments proposed by non-BLM groups on 

federally and non-federally-managed lands within the field office boundaries. In these three field offices, invasive 

plant treatments currently occur on approximately 20 acres annually. For example, subject to available funding, 

the BLM would continue to provide funds to reduce invasive plant infestations, like manual control of policeman’s 

helmet in areas identified as priority sites with partners in Clackamas County and especially in the Sandy Wild and 

Scenic River corridor off of federally-managed lands.

Appendix C, Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan shows how the District would 

continue to treat specific invasive plant species under this Alternative. Similar species are lumped into species

groups (e.g., the biennial thistles species group would have different treatment options than the perennial grasses 

species group). Treatment options would also vary based on considerations such as soil type, infestation size, 

neighboring vegetation, and weather conditions. In addition to treatments shown on the Treatment Key, the 

District would use competitive seeding and planting on an average of 110 acres / year to prevent the introduction 

and spread of invasive plant infestations (average 42 sites / year). The District typically prescribes seeding for soil 

disturbance areas associated with timber sale harvests, culvert replacements and other project sites where the soil 

has been exposed. Competitive restoration planting sites typically number more than a dozen per year across the 

district.

Under the No Action Alternative, the District would continue to treat approximately 1,000 to 6,000 gross acres (on 

average 3,000 gross acres) annually. Approximately 85 percent of those treatments would be with non-herbicide 

methods and 15 percent would be with herbicides. Of the non-herbicide treatments, the majority would be 

manual (42 percent) and mechanical (50 percent), and prescribed fire would account for 7 percent of treatments. 

Of the herbicide treatments, about 98 percent would be with glyphosate. Broadcast treatments with a low boom 

attached to a vehicle would occur occasionally (two times a year) in the West Eugene Wetlands, but all other 

treatments would be spot treatments (applied by backpack sprayer or other ground-based method; see Appendix 

B for more information about ground-based herbicide treatment methods). The Annual Treatment Summary table 

(Table 2-1) shows the last seven years of treatments.

 21 In addition, approximately one acre / year is treated with propane torches as part of the Upper Willamette Field Office’s Oak

Basin restoration project and analyzed in that NEPA analysis (USDI 2011). 

22 As described in Appendix B, Integrated Invasive Plant Management, BLM practice allows for limited and controlled use of 

herbicides that do not have Risk Assessments on demonstration plots up to 5 acres in size, with a maximum of 15 acres per 

Field Office.
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Table 2-1. Northwest Oregon District Annual Treatment Summary (2011-2017)

Treatment Method 2011 acres 2012 acres 2013 acres 2014 acres 2015 acres 2016 acres 2017 acres

Herbicide (total) 214 647 1,023 593 342 97 49

2,4-D 3 5 5 - - - -

Dicamba - 22 10 - 4 - -

Fluazifop-P-butyl - - - - - - <1

Glyphosate 211 620 1,008 593 338 97 48

Picloram - - - - - - -

Manual 1,125 241 2,414 1,616 1,191 1,228 1,041

Mechanical 1,668 1,870 614 1,296 425 2,214 2,561

Targeted Grazing 90 123 - - - - -

Prescribed Fire 172 233 311 261 177 237 37

Biocontrol Agents - - 1 1 - - -

Total Acres Treated 1,229 1,011 3,439 2,210 1,735 3,296 3,321

Inventory1 6,178 14,014 6,989 8,803 10,315 12,516 10,520

1. Further information about invasive plant inventories can be found in Appendix A, Invasive Plants on the District.

Some invasive plants would not be treated under this alternative, as the appropriate treatment method may not 

be available in the area. For example, reed canarygrass and teasel could only be treated in the West Eugene 

Wetlands; they are not listed as noxious weeds and non-herbicide methods are not effective.

The District would manually treat emergent aquatic plants that have a large portion of the plant or leaves out of 

the water if the infestation consisted of one to three stems. The District would not treat larger emergent aquatic 

infestations or submerged and floating aquatic invasive plants.

In the Marys Peak, Tillamook, and Cascades Field Offices, the No Action Alternative in this EA is similar to the No 

Action Alternative (Alternative 2) in the Oregon FEIS, where the BLM estimated overall treatment efficacy at 60 

percent if a limited suite of herbicides were available for use. In the Upper Willamette and Siuslaw Field Offices, 

the No Action Alternative in this EA is most similar to the reference analysis in the Oregon FEIS, where overall 

treatment efficacy was estimated at 30 percent when herbicides were not used. The site-specific analysis of this

can be found in Issue 1.

All treatments are constrained by the Standard Operating Procedures and other measures listed in Appendix D and 

by the herbicide application rates listed in Table B-2 (in Appendix B).

Alternative 2 (Terrestrial Invasive Plant 

Management)

Alternative 2 would replace the management described in the Westside Salem Integrated Non-native Plant 

Management Plan Final Decision and Rationale (USDI 2008d), the Cascades Resource Area Invasive Non-native 

Plant Management Decision Record (USDI 2009), the Marys Peak Resource Area Noxious Weed Control Utilizing 

Glyphosate Final Decision and Rationale (USDI 2010c), and the Categorical Exclusion: Siuslaw Field Office and 

Upper Willamette Field Office Invasive Plant Control (USDI 2018). In addition, it would modify the Sandy Wild and 

Scenic River and State Scenic Waterway Environmental Assessment and Management Plan (USDI 1993).

Alternative 2 would allow the District to treat all terrestrial invasive plants (not just noxious weeds) with 

herbicides, and expand the program to include the use of additional herbicides. The non-herbicide direct control 

methods available under the No Action Alternative would remain the same under Alternative 2. Herbicides 
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available for use under Alternative 2 would include 2,4-D, aminopyralid23, chlorsulfuron, clopyralid, dicamba, 

dicamba + diflufenzopyr, fluroxypyr, glyphosate, hexazinone, imazapic, imazapyr, metsulfuron methyl, picloram, 

rimsulfuron, sulfometuron methyl, and triclopyr. In addition, research and demonstration plots of fluazifop-P-butyl 

and sethoxydim could be used on a maximum of 15 acres per field office24. The same treatment methods would be 

available to all field offices uniformly. In addition, these treatment methods would also be available as BLM 

supports and implements cooperative terrestrial invasive plant treatments, including those proposed by non-BLM 

groups on BLM-administered lands and non-federally-managed lands. This alternative would allow the District to 

participate in and facilitate the implementation of partnership-based invasive plant management projects on nonfederally-managed lands. The District would incorporate these projects in Annual Treatment Plans.

Under this alternative, herbicide use within riparian areas would be allowed (with applicable protection measures)

throughout the District, including on BLM-administered lands within the Sandy Wild and Scenic River Corridor.

Appendix C, Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan, shows how the District would 

treat specific invasive plant species under this alternative. Similar species are lumped into species groups (e.g., the 

biennial thistles species group would have different treatment options than the perennial grasses species group). 

Treatment options would also vary based on considerations such as soil type, infestation size, neighboring 

vegetation, and weather conditions. In addition to treatments shown on the Treatment Key, the District would 

continue to use competitive seeding and planting and prescribed fire. Competitive seeding and planting would 

occur on an average of 110 acres / year to prevent the introduction and spread of invasive plant infestations 

(average 42 sites / year); typical sites being smaller than an acre. Prescribed fire would occur on an average of 400 

acres of invasive plants annually. These prescribed fires could be broadcast fires (across monocultures or areas 

where all species are invasive) or machine or hand piled and burned (generally woody species).

Under this alternative, the District would continue to treat approximately 1,000 to 6,000 gross acres (on average 

3,000 gross acres) annually. As shown in Appendix C, approximately 25 percent of those treatments would be with 

herbicide and 75 percent would be with non-herbicide treatments. Of the non-herbicide treatments, the majority 

would be manual (50 percent) and mechanical (45 percent). About 26 percent of the herbicide treatments would 

be with aminopyralid, 19 percent with glyphosate, 10 percent with imazapyr, and 23 percent with triclopyr. Other 

herbicides would be used 5 percent of the time or less. Herbicide treatments would be spot treatments applied by 

backpack sprayer or other ground-based method 95 percent of the time and broadcast treatments 5 percent of the 

time. See Appendix B for more information about ground-based herbicide treatment methods and the Treatment 

Key in Appendix C for information about how specific infestations would be treated.

As under the No Action Alternative, the District would manually treat emergent aquatic plants that have a large 

portion of the plant or leaves out of the water if the infestation consisted of one to three stems. The District would 

not treat larger emergent aquatic infestations or submerged and floating aquatic invasive plants.

As with the No Action Alternative, all treatments are constrained by the Standard Operating Procedures and other

measures listed in Appendix D and by the herbicide application rates listed on Table B-2. In addition, Appendix D 

lists Project Design Features to reduce the effects of Alternative 2.

As described in the Oregon FEIS to which this EA tiers, the wider range of herbicides from which to choose would 

increase the effectiveness of the average treatment to an estimated 80 percent (USDI 2010a:136). Although some 

 23 BLM practice allows for limited and controlled use of herbicides that do not have Risk Assessments on demonstration plots 

up to 5 acres in size, with a maximum of 15 acres per field office. A Risk Assessment for aminopyralid was completed in 2015 

(AECOM 2015, 2014c), and the herbicide was analyzed at the national level in the 2016 PEIS. This EA provides the additional 

NEPA analysis that would allow the use of aminopyralid on more than 15 acres in the West Eugene Wetlands.

24 As further described in Appendix B, this is not an annual limit. This 15-acre limit could only be exceeded by the issuance of 

ecological and human health Risk Assessments, done or adopted by the BLM, and results evaluated through programmatic 

NEPA analysis done at the National or State level.
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level of retreatment would still take place, the additional herbicides would substantially improve the chances 

invasive plants would be controlled with fewer retreatments (USDI 2010a:135-136). Treatments described under 

this alternative are effective on almost all25 of the types of invasive plant species known to be present on the 

District, including those with potential to be new invaders. The site-specific analysis of this can be found in Chapter 

3.

Alternative 3 (Terrestrial and Aquatic Invasive 

Plant Management)

Alternative 3 would replace the management described in the Westside Salem Integrated Non-native Plant 

Management Plan Final Decision and Rationale (USDI 2008d), the Cascades Resource Area Invasive Non-native 

Plant Management Decision Record (USDI 2009), the Marys Peak Resource Area Noxious Weed Control Utilizing 

Glyphosate Final Decision and Rationale (USDI 2010c), and the Categorical Exclusion: Siuslaw Field Office and 

Upper Willamette Field Office Invasive Plant Control (USDI 2018). In addition, it would modify the Sandy Wild and 

Scenic River and State Scenic Waterway Environmental Assessment and Management Plan (USDI 1993).

Alternative 3 includes all of the terrestrial and emergent aquatic invasive plant treatments described under 

Alternative 2, and adds the treatment of submerged and floating aquatic invasive plants as well as emergent 

aquatic invasive plant infestations that are larger than one to three stems. The District would implement 

integrated invasive plant management for aquatic infestations; treatments of these aquatic invasive plant species 

would occur using manual and mechanical methods and aquatic formulations of 2,4-D, fluridone, glyphosate, 

imazapyr, and triclopyr. There is currently less than one acre of aquatic invasive species currently known on the 

District, all within the Siuslaw Field Office, including three infestations of parrot feather on Hult Pond and an 

emergent infestation of yellow flag iris on Kelly Creek (see Map A-2). These aquatic invasive plants would be a high 

priority for treatment as control programs are most effective if they can eradicate the infestation while it is still in 

the introduction phase before these invasive plant species become established on the District and spread (USDI 

2010a:133, see the Prioritizing Areas for Treatment section in Appendix B). Hence, if Alternative 3 were selected, 

these aquatic plant species would likely be treated as soon as feasible. (See Tables C-3 and C-14 in Appendix C for 

further information about the exact treatment methods that the BLM would use on these species.) Map A-2, 

Aquatic Invasive Species Documented in NISIMS shows the locations of these infestations on the District.

These known aquatic invasive plant infestations occur in the upper reaches of the Willamette River, where there is 

a potential for them to spread rapidly. However, infestations can also occur in isolated closed aquatic systems, 

such as lakes and ponds. Treatments of aquatic invasive plants with fluridone would only occur in closed aquatic 

habitats that do not flow into streams during the treatment window. These are typically ponds and lakes, or 

sloughs and pools of standing water on floodplains connected to rivers only during high water events. Aquatic 

invasive plants in streams and rivers would only be treated with herbicides in areas where a portion of the plant is 

sticking out of the water or when water levels are at their lowest and the invasive plants that were previously 

submerged or floating are no longer in water. (Or stated another way, fluridone would be applied directly to water 

in closed aquatic systems to treat aquatic invasive plants, whereas aquatic formulations of 2,4-D, triclopyr, 

glyphosate, or imazapyr would be applied directly to the foliage of the emergent aquatic invasive plant.)

Appendix C shows treatment options by species group for these aquatic plants. These treatments would likely be 

done in coordination with ODA staff. Manual methods are often used in conjunction with herbicides; while 50 

percent of aquatic treatments would be done with manual methods, it is difficult to remove all viable rhizomes or 

creeping submerged stems from deep sediment and stem fragments can float downstream and establish new 

infestations. Manual treatment methods used on aquatic invasive plants include hand-pulling, rakes, shovels, or 

 25 Submerged and floating aquatic invasive plants are the exception.
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bottom barriers / weed mats, and mechanical methods include diver assisted suction harvest or tractors26.

Treatments may be done via boat; for example, aquatic weeds may be manually pulled out by someone in a kayak.

In the Sandy Wild and Scenic River corridor, BLM would use herbicides in riparian areas on BLM-administered lands 

to treat both terrestrial and aquatic invasive plants when appropriate. Currently there are no known aquatic 

invasive plants in the Sandy River corridor, but this alternative would allow treatment if they are discovered.

These treatment methods would also be available as BLM supports and implements cooperative terrestrial and 

aquatic invasive plant treatments, including those proposed by non-BLM groups on BLM-administered lands and 

non-federally-managed lands. This alternative would allow the District to participate in and facilitate the 

implementation of partnership-based terrestrial and aquatic invasive plant management projects on non-federallymanaged lands. The District would incorporate these projects in Annual Treatment Plans.

As with the other alternatives, all treatments are constrained by the Standard Operating Procedures and other 

Protection Measures listed in Appendix D and by the herbicide application rates listed on Table B-2. Appendix D 

lists Project Design Features adopted for this analysis to reduce the effects of Alternative 3. Project Design 

Features and monitoring described for Alternative 2 also apply to Alternative 3.

As described under Alternative 2, as well as the Oregon FEIS to which this EA tiers, the wider range of herbicides 

from which to choose would increase the effectiveness of the average treatment to an estimated 80 percent (USDI 

2010a:136). Although some level of retreatment would still take place, the additional herbicides would 

substantially improve the chances the District would control invasive plant infestations with fewer retreatments 

(USDI 2010a:135-136). Treatments described under this alternative are effective on all of the invasive plant species 

known to be present on the District, including those with potential to be new invaders. Chapter 3 provides the sitespecific analysis.

Annual Treatment Plan (Alternatives 2 and 3)

Under the action alternatives, the District will determine potential treatments based in part on available tools and 

funding, and develop an Annual Treatment Plan prior to the beginning of control treatments. In addition, the 

District may develop specific area or project treatment plans in coordination with partners. Annual Treatment 

Plans would be subject to an interdisciplinary team27 review, preparation of a Determination of NEPA Adequacy, 

and an additional decision to implement the Plan. This process ensures the proposal is within the scope of the 

program of work analyzed in this EA, and that there is no new information or changed circumstances that would 

change the decision that results from this EA or substantially alter this EA’s analysis. The acres treated described in 

this EA provide analytical assumptions for the issues analyzed in this EA and are not thresholds or targets for 

treatment. Reviewing actions through a Determination of NEPA Adequacy would allow the District to evaluate the 

implementation of this programmatic EA and evaluate whether treatments in the Annual Treatment Plan

(individually and collectively) are within the scope of the program of work authorized. If there is relevant new 

information or changed circumstances, the District would revise Annual Treatment Plans to comply with the 

Decision Record for this EA or would complete the appropriate level of NEPA analysis and issue a new decision. The 

District would post Determinations of NEPA Adequacy and decisions for annual site-specific implementation on 

BLM’s ePlanning website. Annual Treatment Plans help the District ensure that treatments conform to design 

 26 Mechanical methods would not include aquatic weed harvesters.

27 The interdisciplinary teams would include botanists, wildlife and fisheries biologists, archaeologists, and other natural 

resource specialists with expertise in potentially affected resources. Interdisciplinary team review of Annual Treatment Plans 

with broadcast treatments would include natural resource specialists with expertise in soil and hydrology.
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standards and protection measures in the relevant NEPA documents28, that site-specific conditions are considered 

and appropriately mitigated29; and that the District completes required Pesticide Use Proposals, Biological Control 

Agent Release Proposals, and other authorizations, obligations, and commitments30 prior to implementation. 

Unexpected events such as increased or decreased funding, new invaders, wildfire, or weather conditions could 

alter implementation of the Annual Treatment Plan; however, through the Determination of NEPA Adequacy 

process described above the District would evaluate every planned control treatment, including BLM’s 2019 

Annual Treatment Plan. The District bases treatment methods on best current science and the experience of 

invasive plant control professionals. As new information becomes available about effective (or ineffective) 

treatment options for species or species groups, the District would make modifications to the Treatment Key as 

part of the Annual Treatment Plan.

Table C-30 in Appendix C summarizes this calendar year’s invasive plant control activities planned for the District to 

present an example of how priorities and treatment methods would be implemented. However, this EA is 

programmatic, and as such does not authorize specific projects. Subsequent on-the-ground actions require 

additional decision-making before the treatments listed in the Annual Treatment Plan would be implemented.

Summary of Invasive Plant Treatments Under Each 

Alternative

Table 2-2, Comparison of the Alternatives, Treatment Methods provides a summary of the treatment options that 

would be available for use under each alternative.

Table 2-2. Comparison of the Alternatives, Treatment Methods

Treatment

No Action Alternative Alternative 2 Alternative 3

Marys Peak 

and Tillamook 

Field Office

Sandy Wild 

and Scenic 

River Corridor

Cascades 

Field 

Office2

Siuslaw and Upper 

Willamette Field 

Offices1,2

West 

Eugene 

Wetlands

District Wide2 District Wide2

Direct Control Methods: Non-Herbicide Methods

Manual (T3)  (T)  (T)  (T)  (T)  (T)  (A3 and T)

Mechanical  (T)  (T)  (T)  (T)  (T)  (T)  (A and T)

Competitive seeding and 

planting

 (T)  (T)  (T)  (T)  (T)  (T)  (T)

Biological control agents  (T)  (T)  (T)  (T)  (T)  (T)

Prescribed fire  (T)  (T)  (T)  (T)  (T)  (T)

Targeted grazing  (T)  (T)  (T)  (T)  (T)  (T)

Direct Control Methods: Herbicides

2,4-D 5 (limited T) 4 (T)  (T)  (A and T)

Aminopyralid 6 (T)  (T)  (T)

Chlorsulfuron  (T)  (T)

Clopyralid  (T)  (T)  (T)

Dicamba 5 (limited T) 4 (T)  (T)  (T)

Diflufenzopyr + dicamba  (T)  (T)

Fluroxypyr  (T)  (T)

Fluridone  (A)

Fluazifop-P-butyl 6 (T) 6 (T) 6 (T)

 

28 For example, Project Design Features adopted by this EA, Standard Operating Procedures, Mitigation Measures, and 

Conservation Measures (for Special Status species). These are all included in Appendix D. 29 For example, treatments where invasive plant control would remove plants contributing to bank stability or stream shading 

could be delayed or phased as necessary in order to prevent adverse effects to water quality. 30 Such as required Special Status species, archaeological, and paleontological surveys, as well as SHPO consultation.
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Treatment

No Action Alternative Alternative 2 Alternative 3

Marys Peak 

and Tillamook 

Field Office

Sandy Wild 

and Scenic 

River Corridor

Cascades 

Field 

Office2

Siuslaw and Upper 

Willamette Field 

Offices1,2

West 

Eugene 

Wetlands

District Wide2 District Wide2

Glyphosate 4 (T) 5 (limited T) 4 (T)  (T)  (T)  (A and T)

Hexazinone  (T)  (T)

Imazapic  (T)  (T)

Imazapyr  (T)  (A and T)

Metsulfuron methyl  (T)  (T)

Picloram 5 (limited T) 4(T)  (T)  (T)

Rimsulfuron  (T)  (T)

Sethoxydim 6 (T) 6 (T)

Sulfometuron methyl  (T)  (T)

Triclopyr  (T)  (T)  (A and T)

1. Not including the West Eugene Wetlands. 2. Not including the Horning and Tyrrell Seed Orchards.

3. T = terrestrial invasive plant treatments; A = aquatic invasive plant treatments 4. Used on noxious weeds only.

5. Used on noxious weeds only and not used within riparian zones. 6. Used on research and demonstration plots only 

(maximum of 15 acres per herbicide per field office 

without additional NEPA analyses).

Alternatives Considered but Eliminated from 

Detailed Study

The BLM is required to include a discussion of all reasonable alternatives that achieve the purpose and need. 

Reasonable alternatives include alternatives which are technically and economically feasible, and which meet the 

purpose and need for the project. The BLM may eliminate from detailed analysis any alternatives that are not 

reasonable, including if the alternative:

• does not meet the purpose and need;

• is technically or economically infeasible;

• is inconsistent with the basic policy objectives for the management of the area;

• implementation is remote or speculative;

• is substantially similar to an alternative being analyzed in detail; or,

• would have substantially similar effects to an alternative being considered in detail.

The interdisciplinary team considered several other alternatives for analysis during the interdisciplinary process.

The majority of these alternatives were submitted in the form of public comments during scoping. The reasons 

why these alternatives were eliminated from detailed analysis follows.

No Herbicides

This alternative was suggested by public scoping comments on this EA. This alternative would manage invasive 

plants with a full range of treatment methods except herbicides, similar to the current management of the Siuslaw 

and Upper Willamette Field Offices. Some public scoping comments suggested that instead of using herbicides, 

manual treatment of invasive plants could be accomplished with volunteers. This alternative was eliminated from 

detailed study because a no-herbicides reference analysis was included in the Oregon FEIS (USDI 2010a:27) and 

indicated the rate of spread for noxious weeds would increase over time and in turn, the adverse ecological and 

economic impacts of noxious weeds would increase. (This is also explained in Issue 1, which describes the spread 

of invasive plants on the District.) In the Northwest Oregon District, plants that cannot be effectively controlled 

without the use of herbicides include Canada thistle, parrots feather, water primrose, and knotweeds. A noherbicides alternative would not meet the need for more effective invasive plant control and therefore is not a 
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reasonable alternative. In addition, this alternative is inconsistent with the basic policy objectives for the 

management of the area, as established in the District’s Resource Management Plans.

Use Fewer Herbicides than Analyzed Under the Action 

Alternatives

An alternative was considered that would remove one or more herbicides from consideration in the action 

alternatives for various reasons including stated risks or apparent lack of need. All of the herbicides available in the 

action alternatives have specific species or conditions for which they are the most suitable control. This proposed 

alternative would not meet the purpose and need; having the range of herbicides available under Alternative 2 or 

3 would allow applicators to select the most appropriate one for a wider range of invasive plant species, site 

conditions, timing, and management objectives, and help avoid the development of herbicide resistance in target 

invasive plant species (see Appendix B for more discussion of herbicide resistance). This would allow the BLM to 

more effectively control invasive plants to protect native ecosystems and the flora and fauna that depend on 

them. Specific treatments are shown in the Treatment Key (Appendix C) and effects are analyzed in Chapter 3. For 

any herbicide or use, the Decision-maker could modify the selected alternative to remove an herbicide or modify 

its use; however, there are no adverse effects (as described in this EA) that indicate a need to remove any of the 

herbicides. The District would not use herbicides that are not appropriate for the invasive plants or the conditions 

on the District. Hence, this alternative was eliminated from detailed analysis, as it would have substantially similar 

effects to the action alternatives.

Use More Herbicides than Analyzed Under the Action 

Alternatives

This alternative was suggested during scoping. An alternative was considered that would include additional 

herbicides, including herbicides that are not approved for use on BLM-administered lands. Herbicides used on 

BLM-administered lands must be approved by the BLM National Office, and are, by policy, subject to detailed 

ecological and human health risk assessments for wildland applications to help satisfy the requirements of NEPA 

(USDI 2010a:37). However, BLM practice allows for limited and controlled use of new herbicides on demonstration 

plots up to 5 acres in size, with a maximum of 15 acres per field office. Approval to use an herbicide for research 

and demonstration is provided by the BLM National Office after an initial evaluation of Federal Insecticide, 

Fungicide and Rodenticide Act (FIFRA) registration materials and associated risk assessments (USDI 2010a:478).

In addition to the herbicides analyzed in this EA, Risk Assessments have been completed or adopted by the BLM for 

bromacil, diquat, diuron, and tebuthiuron, and the results have been evaluated through the NEPA process (USDI 

2010b). Research and demonstration has been approved on numerous herbicides, including two that the District 

analyzes under the action alternatives (fluazifop-P-butyl and sethoxydim). In general, having a larger range of 

herbicides available allows applicators to select the most appropriate one for a wider range of invasive plant 

species, site conditions, timing, and management objectives, and helps to avoid resistance of targeted species to 

specific herbicides. However, the herbicides available under the action alternatives effectively treat all of the 

invasive plants species present on the District (in varying conditions), as well as invasive plants on neighboring 

lands that have the potential to be new invaders, without unacceptable adverse effects to District resources. At 

this time, additional herbicides are not needed to aid the BLM with its invasive plant program. Since the District 

would not use herbicides that are not appropriate for the invasive plants or the conditions on the District, these 

herbicides would not be applied. Hence, this alternative was eliminated from detailed analysis, as it would have 

substantially similar effects to the action alternatives.
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Use Vinegar, Salt, Soap, Sugar, Wood Chips, Essential Oils, Hot 

Water or Foam, or Other Household Products to control 

Invasive Plants

These products were suggested during scoping as options for invasive plant control instead of or in addition to 

herbicide use. There are several EPA-registered herbicide formulations that have vinegar as the active ingredient, 

but they are not registered with the State of Oregon and / or they are not included on BLM’s list of herbicides 

approved for use on BLM wildlands. The limited number of registered target plants, lack of widespread use on nonBLM-administered lands, and relatively little experience with environmental effects precludes the BLM from 

investing in the risk assessment process for these herbicides. The process for proposing, analyzing, and adopting 

additional herbicides is outlined in Appendix 4 of the 2010 Oregon FEIS (USDI 2010a:477-482), and it is possible 

that a vinegar herbicide could be considered in the future.

A mixture of salt, vinegar, and dish soap was suggested as an invasive plant treatment method in a letter received 

during scoping, as it has the “power of RoundUp [glyphosate product]... will kill any and all vegetation and will 

sterilize the soil so that nothing will grow for a long time.” If this mixture works as described, it does not meet the 

purpose of preventing unacceptable adverse effects. While there can be advantages to having non-selective 

herbicides (such as glyphosate) available in certain circumstances, in general, having more selective treatment 

methods has less risk to non-target vegetation. Sterilizing the soil (by using vinegar, an acid with a pH of 2.2) so 

that nothing will grow would not allow native plants to return; in addition to other adverse effects, soil quality is 

important for nutrient cycling and water holding capacity (Page-Dumroese et al. 2009).

Essential oils can function as herbicides, although they are not registered by the EPA for this use. They are also 

non-selective (Campiglia et al. 2007). Mint oil products are registered as insecticides with the EPA, which suggests 

that they may not be as safe for insects as the herbicides analyzed in this EA. In addition, the costs of essential oils 

far exceeds the costs of treatment methods available under the alternatives.

The addition of carbon (via sugar or wood chips) to soils has been used to control certain annual weeds. In test 

plots, Charles Sturt University (Australia) ecologists spread half a kilogram of refined white sugar to each square 

meter of soil every three months and found this inhibited weed growth of most annual weeds, giving the native 

plants the opportunity to become well-established (Beemster 2005). In addition to being both expensive and timeconsuming, most of the invasive plants found on the district are not annuals; these carbon additions would favor 

the more problematic perennial weeds on the District.

Hot foam treatments have been experimented with on some BLM districts in western Oregon in the past two 

decades, but have not been found to be effective for widespread use. While hot foam prevents seed set, it does 

not kill the seed bank. Hot foam and hot water would have more adverse environmental effects to non-target flora 

and fauna than the proposed treatment methods; hot water and foam are less selective, more time consuming, 

and have higher equipment costs than other available control methods.

Some household products were not considered because Oregon State Law prohibits the use of any material to 

control, kill, limit, or repel plants or animals unless it is registered with the State as a pesticide and such use is 

consistent with the label. Certain household materials are registered pesticides. For example, Clorox Ultra is 

registered for killing the oospores of the root disease Phythophthora lateralis (Port-Orford-cedar root disease), and 

borax is registered for use on tree stumps to prevent the root disease Fomes annosus. Pesticide registration and 

rigorous analysis is required; being a food or household product is not necessarily evidence it would not have 

unacceptable adverse environmental effects. For example, salt and acetic acid (vinegar) have an LD50 of 3,000 to 

3,500, respectively31. While this is lower in toxicity than 2,4-D and triclopyr, it is similar in toxicity to glyphosate, 

 31 Lethal dose to 50 percent of a population. Calculated on rats, as milligrams of substance per kilogram of body mass.
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picloram, and dicamba, and higher toxicity than the other herbicides analyzed in this EA (USDI 2010a:92, OSU 

2015). This alternative was eliminated from detailed analysis as it is technically and economically infeasible, it is 

inconsistent with the basic policy objectives for the management of the area, and it would not meet the purpose 

and need.

Use Non-Herbicide Methods First, Use Herbicides Only Where 

Absolutely Necessary and Decrease Their Use in the Future

This alternative was not considered because existing Department of the Interior policy, applicable to all 

alternatives, states that, “Bureaus will accomplish pest management through cost-effective means that pose the 

least risk to humans, natural and cultural resources, and the environment” and requires bureaus to “Establish site 

management objectives and then choose the lowest risk, most effective approach that is feasible for each pest 

management project” (USDI 2007e), and “Determine, for each target pest, the possible courses of action and 

evaluate relative merits for controlling the pest with the least adverse effects on the environment” (USDI 1992a).

Invasive plants are difficult to control and previous analysis in the 2010 Oregon FEIS and monitoring data show that 

all control methods including herbicide applications (individually or in combination) are necessary to prevent 

undue degradation and promote land health (USDI 2010a, USDI 2010b:18-25). The action alternatives include 

adding use of more selective herbicides that are subject to numerous Project Design Features to reduce potential 

adverse effects. These alternatives also include an adaptive management approach to select the control method 

(herbicide and non-herbicide) that is most effective while minimizing adverse effects.

Given the continued spread of invasive plants and an increasing emphasis on protecting threatened habitats, it is 

unlikely the need for effective invasive plant control would decrease in the foreseeable future (USDI 2010a:139); 

therefore, this proposed alternative would not meet the purpose and need and it is inconsistent with the basic 

policy objectives for the management of the area. In addition, similar to the No Herbicides alternative eliminated

from detailed study, prioritizing the use of non-herbicide methods would have substantially similar effects to the 

action alternatives described in detail in this EA in which mechanical and manual methods are prioritized and 

herbicides are used discriminately. Hence, this alternative was eliminated from detailed analysis.

Limit Herbicide Treatments to Early Detection Rapid Response

An alternative was considered using the herbicides included in the action alternatives, but strictly limiting their use 

to early detection rapid response-type treatments of new sites or new species. Non-herbicide treatments of 

invasive plant sites would continue, but existing invasive plant sites would not be actively controlled with 

herbicides.

This alternative was eliminated from detailed analysis because it does not meet the purpose and need and it is 

inconsistent with the basic policy objectives for the management of the area. Control of established infestations 

essential to preventing or reducing ecologic and economic degradation, and controlling many of these sites cannot 

be achieved without using herbicides. Using herbicides to prevent invasive plant spread to uninfested areas is costeffective and consistent with current laws, administrative direction, and the District’s Resource Management 

Plans.

Include the Use of Herbicides for Native Vegetation

An alternative was considered that would allow herbicides to be used on both invasive and native vegetation to:
Integrated Invasive Plant Management for the Northwest Oregon District

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Chapter 2 – Integrated Invasive Plant Management and the Alternatives

29

• Meet safety and operations objectives (clearing) along roads and around administrative sites. The Oregon 

Department of Transportation and others responsible for road maintenance use herbicides to maintain 

site clearances and protect investments, for example.

• Improve Special Status species habitat. Examples of this could include treatment of native species to 

promote federally listed species habitat restoration.

The need described in Chapter 1 is focused on more effective invasive plant management, and does not include a 

need for more effective native plant management. Therefore, this alternative was eliminated from detailed 

analysis because it does not respond to the purpose and need. However, as described in Issue 1, more effective 

invasive plant management will improve safety and operations objectives around roads and administration sites 

and Special Status species habitat.

Reduce Management Activities Implicated in Invasive Plant 

Spread

This alternative was suggested by public scoping comments on this EA. This alternative would curtail or restrict 

various management and public use activities taking place on BLM-administered lands (such as timber harvest, 

grazing, mining, off-highway vehicles, camping, hiking, wildfire control, or boating) in order to reduce invasive 

plant spread. This alternative is inconsistent with the basic policy objectives for the management of the area, as 

established in the Northwestern and Coastal Oregon Resource Management Plan and Record of Decision (USDI 

2016d) and the West Eugene Wetlands Resource Management Plan and Record of Decision (USDI 2015b). A

reconsideration of the level of various land uses is the purview of the land management planning process 

described in the Federal Land Policy and Management Act (FLPMA) and is beyond the scope of this project to 

change land use plan decisions. A variety of management uses are authorized and directed by the FLPMA, by the 

Oregon and California Lands Act, and by other policy and direction. While these activities variously contribute to 

the spread of invasive plants (and in some cases, to their control), it is the role of each district’s Resource 

Management Plan to identify an appropriate mix of public uses and management practices consistent with land 

capability, long-term productivity, and ecosystem health. The potential for an activity to contribute to the spread 

of noxious weeds and other invasive plants was analyzed in the Final EIS for the Northwestern and Coastal Oregon 

Resource Management Plan and was considered in the decision to select the current Resource Management Plan 

(USDI 2016d:93).
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30

Chapter 3 - Affected Environment and 

Environmental Consequences

This chapter focuses on resource issues analyzed in detail that were identified during scoping, and presents the 

consequences of Alternative 2 and Alternative 3 compared to continuing current management (the No Action 

Alternative). Issues are analyzed in detail when:

a) the issue is related to how the alternatives respond to the purpose and need; or,

b) analysis is necessary to determine the significance of impacts.

Appendix G contains Issues 4 through 28, which the District did not analyze in detail. Many of the issues included in 

Appendix G have already been adequately analyzed in documents to which this EA tiers.

Determination of Effects in this Environmental Analysis

The individual issues analyzed in detail in this chapter and those not analyzed in detail in Appendix G take into 

consideration the following factors:

• Treatment Key (see Tables C-1 through C-27, and C-28, Summary of Treatment Options): This shows 

invasive plant locations and sizes, treatment options under each alternative, considerations for when 

treatment methods would be used, and percent of acres by field office or area where a treatment method 

would be used.

• Risk Assessments: Issues that discuss native vegetation, fish and aquatic organisms, wildlife, and human 

health rely on herbicide Risk Assessments to aid in analyzing and describing adverse effects. Risk 

Assessments quantitatively evaluate the probability (i.e., risk) that herbicide use in wildland settings might 

pose harm to an organism. The analysis describes the potential for the given resource to experience the 

Risk Assessment-modeled exposure scenarios (See Appendix F, Herbicide Risk Assessment Summaries).

The likelihood of actual exposures comparable to those described in the Risk Assessments is reduced by 

application of Protection Measures (see Appendix D), as well as by the nature of the application and the 

location and actions of the receptor.

32

• Protection Measures: Standard Operating Procedures have been identified to reduce adverse effects to 

environmental and human resources from vegetation treatment activities based on guidance in BLM 

manuals and handbooks, regulations, and standard BLM and industry practices. Mitigation Measures were 

identified for all potential adverse effects identified for herbicide applications in the 2007 and 2016 PEISs 

and the Oregon FEIS (USDI 2007a, USDI 2016a, USDI 2010a), and adopted by their Records of Decision 

(USDI 2007b, USDI 2016b, USDI 2010b). Conservation Measures were identified in the 2007 and 2016 

Biological Assessments (USDI 2007c, USDI 2016c) for the 2007 and 2016 PEISs, and minimize adverse 

effects to federally listed species. Mitigation Measures adopted in the 2007 and 2016 PEISs also apply the 

Conservation Measures to other Special Status species. Project Design Criteria adopted in ARBO II (NMFS 

2013, USDI 2013a) further protect federally listed species. The BLM will consult with the U.S. Fish and 

Wildlife Service and National Marine Fisheries Service on actions described in this EA and consultations 

are expected to result in additional Project Design Criteria to protect federally listed species. BLM will 

adopt all additional Project Design Criteria that result from consultation with either agency. In addition, 

Project Design Features have been adopted as part of this analysis’ action alternatives.

 32 For example, a Risk Assessment might indicate a risk to a large mammal if the mammal were directly sprayed. However, 95 

percent of herbicide applications are spot treatments and a large mammal is unlikely to remain in a treatment area while 

treatment is occurring.
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• Other NEPA Analyses: The analysis tiers to the Oregon FEIS and the 2007 and 2016 PEISs (USDI 2007a, 

2010a, 2016a) at the programmatic scale for effects that could be anticipated from herbicide treatments.

Issue 1: How does treatment efficacy under the alternatives affect the 

spread of invasive plants?

Analytical Assumptions and Methods

The BLM considered the following factors in the analysis of this issue:

• Acres and infestations of invasive plants currently on the district;

• The rate of spread of those invasive plant infestations;

• Acres and infestations of invasive plants that would be treated;

• Adequacy of treatment methods on a species or infestation (i.e., is a treatment method available that can 

adequately treat a particular invasive plant species?); and

• Overall effectiveness of the program.

Acres and Infestations of Invasive Plants Currently on the District

As further described in the Affected Environment section, on the Northwest Oregon District, there are currently 81 

species of invasive plants on 49,491 sites of invasive plants mapped on 17,430 gross acres (see Table 3-1). 

Appendix C displays these species, sites, and acreages, organized by 27 species groups and 5 field offices. Many of 

these sites overlap with other invasive plant sites. For example, a site of reed canarygrass may exist in the same 

area as a site of shining geranium and a site of creeping velvetgrass. This 17,430 figure accounts for this overlap. 

Not accounting for overlap, the summation of the acreage of each of these 49,491 sites is 52,088 acres.

In addition (as described in Appendix A), there are species and infestations that have not been mapped. Many of 

these species are widespread throughout the District and precise acreage is unknown. Field office invasive plant 

management staff have estimated approximately how many acres of each species are in need of treatment, but it 

is unknown if they will become a priority for treatment (see the Prioritizing Areas for Treatment section of 

Appendix B). However, these infestations would be mapped before treatments occur. For the purposes of the 

analysis of this issue, the BLM will calculate program-wide efficacy based on mapped acres.

Spread of Invasive Plant Infestations

As described in Appendix B, Spread from Existing Invasive Plant Sites, timber harvest, road construction, and 

recreation can all contribute to invasive plant spread as well as actions such as management of special forest 

products, rights-of-way agreements, road maintenance, and fuels reduction treatments (USDI 2016e:419-438). 

Maps A-3 to A-7 show some of the routes of invasive plant spread.

As described in the Oregon FEIS, the BLM assumes that the rate of spread from each of these existing infestations 

is 12 percent annually (see Table 3-1). This rate of spread was estimated based on BLM and U.S. Forest Service 

data which showed that invasive plants generally spread at an estimated 10 to 15 percent annually (USDI 

2010a:594-603). The projections in the Oregon FEIS were based on noxious weed data and may not hold true for 

other invasive plants (USDI 2010a:595). Nonetheless, in the absence of better data, the BLM assumes in this 

analysis that the rate of spread for all invasive plants is equivalent to the rate for noxious weeds.

It should be noted that within any particular plant community or infestation, the rate of spread would fluctuate 

over time (see Figure 3-1). As described in the Oregon FEIS, the invasive plant invasion process occurs in three 
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Chapter 3 – Affected Environment and Environmental Consequences

32

phases: introduction, establishment, and spread. Once an introduction occurs, a delay or lag phase often takes 

place while an invasive plant becomes established. This phase is followed by a period of rapid growth that 

continues until the invasive plant species reaches the bounds of its new range (USDI 2010a:132).

Figure 3-1. Relationship between Area Occupied by Invasive Plant Species and Time

Invasive plant control programs are the most 

effective in the earliest phases (before 

establishment and rapid spread). Eighty-five 

percent of mapped invasive plant 

infestations are smaller than one acre (Table 

A-1, Summary of Invasive Plants Documented 

in NISIMS by Infestation Size). These sites are 

a higher priority for treatment, in part 

because they are closer to the introduction 

phase of the invasion curve, where if 

effective treatments are available, control of 

the infestation and eradication is more likely. 

Two percent of sites are larger than 5 acres, 

but account for 39 percent of mapped acres 

(Table A-1). As described in the Prioritizing 

Areas for Treatment section in Appendix B, 

these larger sites would be treated to 

prevent spread (containment), but not for eradication.

Acres and Infestations of Invasive Plants Treated

The District would not treat all invasive plants or all infestations. As described in Chapter 2, the District treats 

between 1,000 and 6,000 acres a year, with an annual average of 3,000 acres (see Table 3-1). This would not 

change between alternatives. These acres would be selected based on type of species, location, potential for 

spread, and efficacy of available treatments. Further information can be found in Appendix B, in the Prioritizing 

Areas for Treatment section.

Under all alternatives, when invasive plant treatments occur, all invasive plant species within the project area that 

can be treated are treated; the removal of only one species at a site where several species are intermingled would 

lead to the other invasive plants at the site revegetating the area. Hence, the District’s approximately 3,000 acres 

of annual treatments occur within the existing 17,430 acres of invasive plant infestations, which takes into account 

that species overlap (i.e., treating 3,000 acres treats 17 percent of the District’s currently mapped invasive plant 

infestations).

Adequacy of Treatment Methods

Treatments would be done according to the Treatment Key (see Appendix C), which lays out treatment options and 

considerations by species groups and by alternative. As shown in the Treatment Key, many species group tables 

include a row for “no adequate control.” This indicates the percent of acres under each alternative targeted for 

treatment that the District would not treat because adequate control methods are unavailable or unfeasible (e.g., 

infestations are too large or too established to be treated). Treatments would not be attempted even in high 

priority circumstances. Table 3-1 presents acres that cannot be treated, organized by alternative. (As described in the 

Acres and Infestations of Invasive Plants Currently on the District section above, invasive plant infestations often 

overlap. An infestation of one species that can be adequately controlled with available treatment methods may 

treated in the same area as a species that does not have an effective control method (and hence, would not be 

treated). For purposes of this analysis, Table 3-1 provides a weighted acreage by species or location.)
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Effectiveness of the Program

As described in the Oregon FEIS, invasive plant control treatments are not 100 percent effective at controlling all 

treated populations; some level of retreatment is necessary to eradicate or prevent the spread of invasive plants 

(USDI 2010a:135-139). Plants continue to exist in an area after treatments because of the seed bank or propagules 

left behind or because some weeds are inadvertently missed during spot treatments.

The Oregon FEIS described that noxious weed treatments in a program where herbicides were not used had been 

found to be 30 percent effective (USDI 2010a:136); that is, 30 percent of the treated part of the infestation would 

not need follow-up treatments. The Oregon FEIS based this estimate (in part) off of data collected from the former 

Eugene District where herbicides are not used33. Hence, the District estimates noxious weed treatments in the 

Siuslaw and Upper Willamette Field Offices (the former Eugene District), as well as noxious weed treatments in the 

riparian zones in the Sandy Wild and Scenic River corridor, to be 30 percent effective. In addition, the District has 

treated invasive plants not listed as noxious weeds for more than a decade and determined the retreatment rate 

for those species is similar. Hence, under the No Action Alternative, the District estimates treatment efficacy to 

also be 30 percent for invasive plants not listed as noxious weeds. With 30 percent effectiveness and a 12 percent 

spread rate, if an area were treated annually, after 21 years the density of that area would be less than 1 percent 

of what it was when treatments started.

The Oregon FEIS estimated that program effectiveness would be 60 percent in a program where a limited suite of 

herbicides were available. The Oregon FEIS based this estimate off of data collected from districts where only 2,4-

D, dicamba, picloram, and glyphosate were used (USDI 2010a:136). Hence, treatment efficacy is estimated to be 60 

percent for noxious weeds in the Cascades, Marys Peak, and Tillamook Field Offices under the No Action 

Alternative. With 60 percent effectiveness and a 12 percent spread rate, if an area were treated annually, after 

seven years the density of that area would be less than 1 percent of what it was when treatments started.

The Oregon FEIS estimated that program effectiveness would be 80 percent in a program where the suite of 

treatment methods and available herbicides would be sufficiently broad for treatments to meet the program’s 

invasive plant management objectives (USDI 2010a:136). Hence, treatment efficacy is estimated to be 80 percent 

for most terrestrial plants under the action alternatives. With 80 percent effectiveness and a 12 percent spread 

rate, if an area were treated annually, after five years the density of that area would be less than 1 percent of what 

it was when treatments started. However, perennial grasses would continue to have limited effective treatment 

methods available, so effectiveness for these species is estimated at 60 percent.

As shown in Table 2-2, the West Eugene Wetlands program includes more herbicides and treatment methods than 

the other field offices and locations on the District; however, treatment efficacy would still be lower than what 

would be achieved with a broader suite of treatment methods. The District estimates treatment efficacy to be 70 

percent for the West Eugene Wetlands for invasive plants under the No Action Alternative. With 70 percent 

effectiveness and a 12 percent spread rate, if an area were treated annually, after six years the density of that area 

would be less than 1 percent of what it was when treatments started.

Except for the possibility of early detection and rapid response manual treatments on up to three stems of 

emergent aquatic infestations, the District would not attempt to control aquatic invasive plant infestations under 

the No Action Alternative and Alternative 2. The District estimates aquatic treatment efficacy to be 80 percent 

under Alternative 3.

These projections of effectiveness should not be considered absolute, but rather reasonable approximations of the 

relative differences among the alternatives. Table 3-1 illustrates these varying levels of treatment effectiveness 

across the District under the alternatives.

 33 The Oregon FEIS also used data from National Forests in Oregon where herbicides had not been used (USDI 2010a:136). 
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Table 3-1. Summary of Factors that Affect the Spread of Invasive Plants 

Species or Locations with Varying Treatment 

Effectiveness

Treatment 

Effectiveness

Total Infested 

Area (Acres1)

Acres1 with No 

Adequate 

Treatment Method

Annual 

Spread 

Rate

Acres1

Treated 

Annually

No Action Alternative

West Eugene Wetlands 70% 595 198

12% 3,000

Marys Peak, Tillamook, and 

Cascades Field Offices2

Noxious Weeds 60% 4,608

Other Invasive Plants 30% 100 1,750

Sandy Wild and Scenic River Riparian Areas 30% 15

Upper Willamette and Siuslaw Field Offices3 30% 12,111 5,461

Aquatic invasive plants (NA4) 1 1

District-wide Varies 17,430 7,409

Alternative 2

Invasive grasses 60% 1,508 128

12% 3,000 Aquatic invasive plants (NA) 1 1

All other invasive plants 80% 15,921 0

District-wide Varies 17,430 129

Alternative 3

Invasive grasses 60% 1,508 128

12% 3,000 Aquatic invasive plants 80% 1 0

All other invasive plants 80% 15,922 0

District-wide Varies 17,430 128

1. As described in Acres and Infestations of Invasive Plants, Adequacy of Treatment Methods, and Acres and Infestations of Invasive Plants 

Treated sections above, invasive plants species on these individual acres may overlap with other invasive plant species. 

2. Not including the Sandy Wild and Scenic River Riparian Areas.

3. Not including West Eugene Wetlands.

4. Not applicable; treatments do not occur.

The analysis area includes locations where invasive plants species are found on BLM-administered lands on the 

District as well as areas where these species are found on non-federal land in partnership project areas. The 

temporal scale of the analysis is 15 years. This is a long enough timeframe to show a comparison between the 

alternatives; however, variables in new introductions of invasive plants over time are too uncertain to allow for a 

useful analysis beyond this.

Affected Environment

As further described in Appendices A, Invasive Plants on the District, and C, Treatment Key, Invasive Plant Sites, and 

the Annual Treatment Plan, the District identified 120 invasive plant species known or suspected to occur on the 

District. Of those, 53 species are not listed as noxious weeds. The District has mapped 81 invasive plant species on 

over 49,000 sites, totaling more than 17,000 infested acres (Table A-3, Invasive Plants Mapped in NISIMS by 

Infestation Size, Maps A-1, Terrestrial Invasive Species Documented in NISIMS, and Map A-2, Aquatic Invasive 

Species Documented in NISIMS). In addition, there are species and infestations that are known to occur on the 

District but are not mapped. These species are generally widespread and / or dispersed throughout the District. 

While the locations are not mapped, it is possible to characterize the areas and habitat where they may occur. 

While the precise acreage occupied by these species on the District is unknown, the unmapped acres column in the 

tables in Appendix C indicates how many additional acres invasive plant management staff estimate to be in need 

of treatment. Most infestations on the Northwest Oregon District occur on roadsides within forests, at recreation 

sites, in meadows, and in forest openings where invasive plants have more access to sunlight and less competition 

from native woody plants. Two aquatic invasive species are mapped on the District. Appendix C describes in 

additional detail the District’s invasive plant species and infestations.
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Environmental Consequences

This analysis shows how the alternatives would affect spread of the current infestations. It does not account for 

unknown infestations on neighboring lands that would spread on to BLM-administered lands. Likewise, 

infestations on BLM-administered lands would spread on to non-BLM-administered lands, where they may or may 

not be treated. Exact data are unknown; as described in the Proposed Resource Management Plan / Final 

Environmental Impact Statement for Resource Management Plans for Western Oregon, the distribution of invasive 

plant species across all lands is available on the iMapInvasives website. However, as described in the Proposed 

Resource Management Plan and Final Environmental Impact Statement for Resource Management Plans for 

Western Oregon, to which this EA tiers, the data are limited because there is no requirement for county, private, or 

corporate landowners to report invasive plant information (USDI 2016e:245). The alternatives could cumulatively 

contribute to spread on these other lands or may cumulatively aid in the reduction of spread.

As described in the Oregon FEIS, under all alternatives, treatment efficacy would be beneficially affected by 

restoration projects and right of way maintenance when these projects incidentally control invasive plants (USDI 

2010a:154). The Oregon FEIS estimates that 25 percent of right-of-way maintenance incidentally treats undetected 

noxious weeds (USDI 2010a:137).

No Action Alternative

Under the No Action Alternative, the District would treat approximately 3,000 acres per year. Invasive plants 

would continue to spread at their current rate, estimated at 12 percent per year. Given a 12 percent rate of spread 

and annual treatment of 3,000 acres per year at a 30, 60, or 70 percent effective treatment rate depending on the 

species and location, as well as 7,409 acres that have no adequate treatment method, the 17,430 acres of mapped 

infestations is estimated to spread to 51,968 acres over the next 15 years. The effective annual increase in infested 

acres in year 15 would be 198 percent, meaning that despite a combination of prevention efforts and control 

treatments, spread would rapidly outpace rate of control. This varies by field office: in the Cascades, Marys Peak, 

and Tillamook Field Offices, infestations would increase 108 percent (from 4,608 acres to 9,578 acres) over 15 

years and infestations in the Upper Willamette and Siuslaw Field Offices would grow 238 percent (from 12,227 

acres to 41,305 acres).

This spread is influenced both by program’s treatment effectiveness but also by the quantity of acres without 

adequate treatment methods. As shown in Appendix C, all of the 27 species groups have inadequate treatments 

for some portion of the District. As shown in Figure 3-2, in Cascades, Marys Peak, and Tillamook Field Offices 

where overall program effectiveness is 60 percent for noxious weeds, this means that existing mapped infestations 

would reduce from the current infestation size of 4,608 acres to 2,993 acres in the next four years. However, acres 

that could not be treated would continue to grow 12 percent a year, and hence grow from 2,993 to 9,578 acres 

over the next 11 years.

Table 3-2 shows the existing acres (mapped and estimated) that cannot be controlled as well as the projected 

spread of those acres after 15 years. Many species groups do not have adequate treatment methods for 

infestations in some areas, but those species also do not have any acreage in many areas. For example, there are 

no treatment methods available to treat aquatic species under this alternative, but there are no known 

infestations in the Upper Willamette Field Office. Hence, after 15 years, there would be no spread from known 

infestations in this field office. Biological control agents may also affect spread; as described in the Biological 

Control Agents section of Appendix B, biocontrols are effective when there are enough invasive plants for the 

agent to feed on.

The BLM works in conjunction with other landowners off of BLM-administered lands on approximately 20 acres 

annually. Effects on these acres would be as described on BLM-administered lands, as projects are limited to the 

same restrictions and treatment methods available to the BLM. Due to the limited treatment methods available 
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under this alternative, some partners have stopped collaborating with the BLM on projects off of BLMadministered lands so they can use more effective methods of treatment.

Figure 3-2. Acres of Invasive Plants, 15 year Projection (No Action Alternative)

Other neighboring infestations 

cannot be quantified; it is 

unknown how many acres exist, 

whether treatments are being 

done, and if they are, how 

effective they are. Given that the 

BLM administers 7 percent of the 

land within the District boundary 

and that land is dispersed across 

the northwest quarter of the 

state, it is likely that tens of 

thousands of acres of invasive 

plants may spread onto BLMadministered land in the next 15 

years. Likewise, invasive plants 

on BLM-administered lands will 

spread off of BLM-administered 

lands. The inability to effectively control species on BLM-administered land results in the spread of infestations to 

other landowners. Even if those landowners have more effective treatment options, their long-term success would 

be reduced because infestations on BLM-administered lands would continue to provide a seed or propagule 

source. Thus, the opportunity to collaborate in an all-lands strategy to control these species would be 

compromised. Ultimately, limited treatment efficacy on BLM- administered lands would reduce treatment efficacy 

at the landscape scale. In addition, potential partners have been reluctant to engage in cooperative control due to 

BLM’s herbicide use restrictions and resulting confusion and complication of switching treatments at ownership 

boundaries.

As appropriate, the impact of invasive plant spread described under this alternative to other resources is discussed 

in Issue sections related to those resources (see Issues 2 and 3 and Appendix G).

 -

 5,000

 10,000

 15,000

 20,000

 25,000

 30,000

 35,000

 40,000

 45,000

Year 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Marys Peak, Tillamook, and Cascades Field Offices

Upper Willamette and Siuslaw Field Offices
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Table 3-2. Acres With No Adequate Control Methods, by Species Group, No Action Alternative1

Area

Species Groups

Upper Willamette

Field Office Siuslaw Field Office West Eugene Wetlands

Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office

Current Infestation 

in 15 Years2 Current Infestation in 15 Years2 Current Infestation in 15 Years2 Current Infestation in 15 Years2 Current Infestation in 15 Years2 Current Infestation in 15 Years2

Annual Grasses 03 0 -3 - 0 1 - - - - 2 9

Annual Peas 9 49 98 538 NA4 NA - - 0 1 - -

Aquatic Species - - 0 2 - - - - - - - -

Biennial Thistles 596 3,2615 15 83 265 1,4505 547 2,9965 614 3,3625 39 213

Borage - - 1 4 - - - - - - 0 0

Buckwheat 2 9 1,264 6,920 NA NA 2 9 5 28 19 103

Buttercups - - 0 0 NA NA 0 0 0 2 10 55

Canada Thistle 1,194 6,5345 - - NA NA 709 3,8835 798 4,3675 87 477

Carnations - - - - - - - - - - - -

Carrot - - 1 4 - - - - - - 0 1

Geranium 210 1,147 135 741 12 67 111 608 90 490 45 248

Hawkweeds - - - - NA NA - - - - 0 0

Knapweeds 22 120 250 1,3685 NA NA 13 72 22 123 37 200

Lilies, Iris, Sedges, Rushes - - 0 1 - - - - - - - -

Loosestrifes - - 0 2 - - - - - - - -

Miscellaneous Herbaceous - Annual - - 0 2 NA NA - - - - 0 2

Miscellaneous Herbaceous - Perennial 4 21 8 44 NA NA 0 1 0 1 3 18

Mustards - - 0 0 NA NA 6 34 0 0 0 0

Perennial Grasses 609 3,332 246 1,346 445 2,436 52 284 309 1,689 247 1,350

Perennial Mints 0 2 0 3 NA NA - - - - 2 8

Perennial Peas 16 85 8 45 NA NA 108 591 2 10 3 14

Snapdragons 713 3,901 1,495 8,182 - - 1 8 2 9 18 99

Spurges - - - - - - - - - - 0 1

St. Johnswort 2,006 10,9775 1,950 10,6765 NA NA 186 1,0205 209 1,1465 20 109

Sunflower 604 3,3055 709 3,8825 NA NA 99 544 112 616 35 194

Teasel - - - - NA NA - - - - - -

Woody 4,307 23,574 3,433 18,789 NA NA 900 4,927 483 2,645 427 2,339

1. White cells = < 1 acre, yellow cells = 1 to 100 acres, and pink cells > 100 acres. Colors do not indicate any sort of threshold. These acres do not add up to the 7,409 acres shown in Table 3-1. Table 

3-1 accounts for species with overlapping acreage; however, many species with overlapping acres are in separate species groups. In addition, this table shows mapped acres as well as additional 

estimated acres in each species group in need of treatment.

2. While current infestations are on BLM-administered lands, infestations may spread beyond the geographic area in which they currently occur.

3. 0 acres in an area indicates that the acreage rounds to 0 (acreage is less than 0.5). A dash indicates that the species is not present in an area.

4. NA = adequate control methods available for this species group in this area.

5. In these species groups and geographic areas, 15-year infestation acres are expected to be overestimates. Biocontrol control agents are effective on at least 90 percent of the invasive plants in 

these species groups in these areas (see Table B-1, Widespread Biological Control Agents in the Northwest Oregon District and as described in Appendix B, Biological Control Agents, biocontrols are 

only effective when there are enough invasive plants for the agent to feed on.)
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Alternative 2

Figure 3-3. Acres of Invasive Plants, 15 year Projection (Alternative 2)

Under Alternative 2, the District would 

treat approximately 3,000 acres per year. 

Invasive plants would continue to spread at 

their current rate, estimated at 12 percent 

per year. Given a 12 percent rate of spread 

and annual treatment of 3,000 acres per 

year at a 60 or 80 percent effective 

treatment rate, the existing 17,430 acres of 

mapped terrestrial infestations is 

estimated to be reduced to 705 acres over 

the next 15 years, a 96 percent reduction. 

Similar to the No Action Alternative and as 

shown in Figure 3-3, existing mapped 

infestations would reduce from the current 

infestation size of 17,430 acres to 627

acres in the next 14 years. However, acres 

that could not be treated because adequate treatment methods are not available would continue to grow 12 

percent a year, and hence grow from 627 to 705 acres over the next year.

Table 3-3. Acres With No Adequate Control Methods, by Species Group, Alternative 21

Table 3-3 shows the existing acres (mapped and 

estimated) that cannot be controlled as well as the 

projected spread of those acres after 15 years.

This spread does not account for the unknown 

infestations on neighboring lands that would spread onto

BLM-administered lands. However, given the more effective treatment methods available, as well as the existing 

prioritization of small invasive plant sites, these new infestations would be eradicated while they are in the 

introduction or establishment phase. While it is not possible to quantify this influence on the rate of spread, it can 

be assumed that this would result in a reduction in the spread rate (USDI 2010a:137-138). As described in the 

Oregon FEIS (USDI 2010a:133), implementing control efforts in this phase can prevent future infestations on tens 

to hundreds of times more acres (Radtke and Davis 2000)34. The Oregon FEIS describes that the resource value 

benefits from being able to treat weeds as aggressively as adjacent landowners cannot be quantified (USDI 

2010a:327), and that BLM would be perceived as a more equal partner in invasive plant control efforts (USDI 

2010a:325). Partnership projects are more likely to occur under the action alternatives and the BLM would have 

the ability to be strategic in targeting new invaders and other infestations early in the invasion curve (see Figure 3-

1).

Alternative 3

In addition to terrestrial treatments, the District would treat aquatic infestations under Alternative 3. There is 

currently less than one acre of these infestations. The infestations would be high priority for treatment and it is 

expected that these treatments would eliminate these known infestations within three years (see Table 3-4). 

However, the District has not been able to treat aquatic infestations and hence has not been inventorying them. It 

is expected that there are additional unmapped acres throughout the District. In addition, (similar to terrestrial 

species), various vectors (such as recreation activities) have the ability to add new invaders into aquatic systems at 

 34 An updated version of this 2000 report is cited in this EA as ODA (2014). See Issue 23.

Species Groups Current 15 Years

Aquatic Species 0.32 1.75

Lilies, Iris, Sedges, Rushes Group 0.19 1.04

Perennial Grasses 128.30 702.23

All other Species Groups NA1 NA1

1. Adequate control methods available for these species groups

 -

 2,000.00

 4,000.00

 6,000.00

 8,000.00

 10,000.00

 12,000.00

 14,000.00

 16,000.00

 18,000.00

 20,000.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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any time. To support the proper function of aquatic systems , BLM needs the ability to go beyond early detection, 

rapid response to actively treat and effectively control aquatic invasive species.

Table 3-4. Projected Infestation Size Over 15 Years, Aquatic Infestations, Alternative 3

Partnership projects are more likely to occur under the action 

alternatives and the BLM would be able to be strategic in targeting 

new aquatic invaders and other infestations early in the invasion 

curve (see Figure 3-1). For example, Alternative 3 would allow the 

BLM to coordinate with other land managers to control aquatic 

species not yet known on BLM-administered lands, but known to 

occur on adjacent lands such as Eurasian watermilfoil, water 

primrose, and floating water primrose. The BLM would start actively 

participating with the Willamette Aquatic Invasive Network. This 

group has been active in water primrose survey, mapping, and treatments along the Willamette, Luckiamute, and 

Long Tom Rivers, all of which flow through BLM-administered lands.

Spread of terrestrial invasive plants under Alternative 3 would be as described under Alternative 2.

Issue 2: What are the effects to Special Status aquatic species from 

aquatic invasive plant treatments?

Analytical Methods

The analysis area includes any area on the Northwest Oregon District which could potentially receive treatments to 

control aquatic invasive plants, which is any water source found on the District. Therefore, the aquatic analysis 

area includes all of the large rivers, streams, springs, ponds, pump chances, heliponds, and reservoirs on BLMadministered lands on the Northwest Oregon District. The District primarily includes lands in the Willamette basin

and its tributaries along with drainages along the coast range flowing directly into the Pacific Ocean.

Analysis of effects to aquatic organisms from herbicide treatments is based on the Risk Assessments conducted for 

the individual herbicides (see Appendix F and Table 3-6 later in this Issue), and on proposed application rates and 

treatment acres as described in Chapter 2 of this EA. The intensity and duration of effects are described as follows:

Short term: A change in a resource or its condition lasting less than one year.

Long term: A change in a resource or its condition lasting greater than one year.

Negligible: The impact would not be detectable or measurable to aquatic habitat or aquatic species.

Minor localized effect: Short-term changes to aquatic habitat or aquatic species would be measurable or 

perceptible in small localized habitats, but would fall within the range of natural variability and would 

result in no appreciable changes to aquatic species or their habitats beyond the scale of an individual 

habitat unit (e.g., a single pool).

Conclusions described below are based on the review of existing data (e.g., the chapter on forest chemicals 

contained in Influences of Forest and Rangeland Management on Salmonid Fishes and Their Habitats, Meehan 

1991) and other data including spatial data; utilization of professional research and literature; and use of expertise, 

both internal and external, that is based on documented substantiated professional rationale.

The analysis of effects on western pond turtle and painted turtle is discussed in Issue 9 in Appendix G.

Invasive Aquatic Weeds

Original infestation size / Year 0 0.51

Spread rate 12%

Percent effectiveness 80%

Acres treated annually 0.51

Acres effectively treated annually 0.41

Acres of invasive plant 

infestation based on 

original infestation

Year 1 0.10

Year 2 0.02

Year 3 0.00
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Affected Environment

Habitat conditions across the District’s 714,395 acres vary greatly and range from relatively intact, functioning 

ecosystems to degraded systems. Stream habitats are greatly influenced by adjacent riparian stand conditions that 

contribute large and small functional wood, gravel substrate from adjacent hillslopes, and include shade providing 

trees and vegetation to maintain cool stream temperatures required by salmonids. While the lowland valley of the 

Willamette River has been largely converted to agricultural, industrial, and urban uses, much of the upland and 

headwater reaches on BLM-administered lands are forested and habitat conditions in those streams are within the 

range of natural variability seen across any regional landscape. Habitat modification through historical stream 

cleaning, riparian harvest, and road construction are all factors in the reduction of spawning and rearing habitat for 

salmonids in the basin.

The distribution of anadromous stocks of salmon and steelhead in the Willamette River basin has been altered by 

multiple-use dams on both the Willamette and McKenzie River. There are 13 dams within the Willamette Project 

area that are operated in cooperation between the U.S. Army Corps of Engineers (which operates and maintains 

the dams and revetments), the Bonneville Power Administration (which markets the hydropower generated at the 

dams), and the U.S. Bureau of Reclamation (which sells a portion of the water) (NMFS 2008). Willamette Project 

dams block access to a substantial portion of the historical habitat and adversely impacts habitat downstream of 

the dams. The dams contribute to habitat loss, altered water temperatures, and altered flows that impact channel 

structure and floodplain connectivity (NMFS 2008).

Similarly for the Coastal Recovery Unit of the bull trout, fish passage is listed as one the primary threats to the 

species. Reintroductions of bull trout in the Willamette and McKenzie Rivers above Hills Creek Dam have proved 

successful in establishing self-sustaining populations (USDI 2015c:A-24).

There are 25,540 miles of fish-bearing streams within the boundary of the Northwest Oregon District and 1,980 

miles (7.8 percent) are on BLM-administered lands. There are eight federally threatened species and numerous 

other Bureau Sensitive aquatic fauna species throughout the District (Table 3-5). Steelhead trout, coho salmon, 

and Chinook salmon are highly prized game fish that are fished year round in the Willamette River and tributaries. 

Resident rainbow and cutthroat trout are present in many smaller tributaries and are also popular sport fish.

The Northwest Oregon District lacks comprehensive surveys for Bureau Sensitive invertebrate species. However,

their distributions are similarly affected by stream and off-channel habitat conditions as salmonids. Invertebrates 

are affected by a variety of water quality indicators, including sediment, temperature, and dissolved oxygen. For 

example, where streams have multiple road crossings or are highly segmented by the road network, contribution 

of fine sediment has reduced availability of clean gravel substrate for riffle-associated species. Where aquatic 

invasive species have encroached on native species, food webs and habitat availability for aquatic invertebrates

are altered (Kuehne et al. 2016).

Table 3-5. Aquatic Federally-Listed and Special Status Species within the Northwest Oregon District.

Common Name (Distinct Population Segment) Species Listing status Taxon

Coho salmon (Oregon Coast) Oncorhynchus kisutch Federal threatened Anadromous Fish

Coho salmon (Lower Columbia River) Oncorhynchus kisutch Federal threatened Anadromous Fish

Steelhead (Upper Willamette River) Oncorhynchus mykiss Federal threatened Anadromous Fish

Steelhead (Lower Columbia River) Oncorhynchus mykiss Federal threatened Anadromous Fish

Steelhead (Oregon Coast) Oncorhynchus mykiss Bureau Sensitive Anadromous Fish

Chinook salmon (Upper Willamette River) Oncorhynchus tshawytscha Federal threatened Anadromous Fish

Chinook salmon (Lower Columbia River) Oncorhynchus tshawytscha Federal threatened Anadromous Fish

Bull trout Salvelinus confluentus Federal threatened Resident Fish

Pacific eulachon (Southern) Thaleichthys pacificus Federal threatened Anadromous Fish

Pacific lamprey Entosphenus tridentatus Bureau Sensitive Anadromous Fish
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Common Name (Distinct Population Segment) Species Listing status Taxon

Coastal cutthroat trout (Southwest

Washington / Columbia River) Oncorhynchus clarkii clarkii Bureau Sensitive Anadromous Fish

Chum salmon (Pacific Coast) Oncorhynchus keta Bureau Sensitive Anadromous Fish

Puget oregonian Cryptomastix devia Bureau Sensitive Class Gastropoda

Olympia pebblesnail Fluminicola virens Bureau Sensitive Class Gastropoda

Columbia sideband Monadenia fidelis columbiana Bureau Sensitive Class Gastropoda

Pacific walker Pomatiopsis californica Bureau Sensitive Class Gastropoda

Crowned tightcoil Pristiloma pilsbryi Bureau Sensitive Class Gastropoda

Shiny tightcoil Pristiloma wascoense Bureau Sensitive Class Gastropoda

Crater Lake tightcoil Pristiloma crateris Bureau Sensitive Class Gastropoda

Western ridged mussel Gonidea angulata Bureau Sensitive Class Bivalvia

Haddock's rhyacophilan caddisfly Rhyacophila haddocki Bureau Sensitive Order Tricoptera

Scott's apatanian caddisfly Allomyia scotti Bureau Sensitive Order Tricoptera

Treatments Planned Related to the Issue

No Action Alternative and Alternative 2

Manual methods would be used to control emergent aquatic plants if the infestation consists of one to three 

stems. Larger emergent aquatic infestations and submerged and floating aquatic vegetation would not be treated. 

Alternative 3

Herbicide treatments with aquatic formulations could be implemented directly in aquatic habitat. Alternative 3 

includes the use of fluridone in closed aquatic habitats that are disconnected and do not flow into streams during 

the treatment window. In addition, aquatic formulations of 2,4-D, glyphosate, imazapyr, and triclopyr would be 

used in areas where a portion of the plant is sticking out of the water or when water levels are at their lowest and 

the invasive plants that were previously submerged or floating are no longer in water. Manual treatment methods 

used on aquatic invasive plants include hand-pulling, rakes, shovels, or bottom barriers / weed mats and 

mechanical methods include diver assisted suction harvest or tractors. Manual methods would be used to treat 

aquatic plants 50 percent of the time and triclopyr would be used 35 percent of the time. Imazapyr (4 percent),

glyphosate (10 percent), and mechanical methods (1 percent) would also be used in limited situations. The use of 

fluridone and 2,4-D is proposed in very limited situations (less than 1 percent of the time). Treatments may be 

done via boat; for example, aquatic weeds may be manually pulled out by someone in a kayak. As shown on Map 

A-2, there are currently 0.32 acres of parrot feather (an aquatic invasive plant) located in Hult Pond (see Table C-3)

and 0.19 acres of yellow flag iris on Kelly Creek (see Table C-14).

Protection Measures

Standard Operating Procedures and Mitigation Measures for All 

Alternatives Relevant to the Issue

There are numerous required Protection Measures that have been developed to protect water resources, riparian 

and aquatic habitat, and aquatic organisms, and are listed in full in Appendix D. Some of the ones most relevant to 

this issue include:

• For treatment of aquatic vegetation, 1) treat only that portion of the aquatic system necessary to meet 

vegetation management objectives, 2) use the appropriate application method to minimize potential for 
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42

injury to desirable vegetation and aquatic organisms, and 3) follow water use restrictions on the herbicide 

label.

• Minimize treatments near fish-bearing water bodies during periods when fish are in life stages most 

sensitive to the herbicide(s) used, and use spot treatments rather than broadcast treatments35.

• Conduct mixing and loading operations in an area where an accidental spill would not contaminate an 

aquatic body.

• Do not rinse spray tanks in or near water bodies.

• Consider the proximity of application areas to salmonid habitat and the possible effects of herbicides on 

riparian and aquatic vegetation. Maintain appropriate buffer zones around salmonid-bearing streams.

In addition, projects that have the potential to disturb Special Status fish or other aquatic species habitat require 

pre-project clearances, including review for potential habitat and / or project site surveys (USDI 2008b).

Project Design Features Adopted for Alternative 3

The following Project Design Features would further reduce effects on fish and other aquatic organisms under 

Alternative 3:

• In waterbodies that contain federally threatened or endangered fish species or provide critical habitat, 

follow all Project Design Criteria developed in coordination with NMFS.

• Delay treating side channels and connected backwaters until they are disconnected from the mainstem 

river or during the period of lowest flow.

• When using aquatic 2,4-D, glyphosate, imazapyr, or triclopyr in closed aquatic systems, implement a 

phased treatment (treating less than 50 percent of the surface area of the pond at a time) to reduce the 

likelihood of all of the aquatic plants dying at the same time, which would result in a rapid depletion of 

dissolved oxygen.

Environmental Consequences

Direct and Indirect Effects

No Action and Alternative 2

Known aquatic invasive plant sites would not be treated with herbicides under these alternatives. Existing 

infestations would continue to spread at an estimated 12 percent annually; the 0.51 acres of aquatic invasive 

plants currently known on the District would be expected to increase to 1.41 acres in 10 years and 4.39 acres in 20 

years. Unmapped infestations will continue to expand until detected and mapped, which will further add to the 

overall acreage across the District at a similar rate to existing known sites. Manual methods would be used to 

control emergent aquatic plants if the infestation consists of one to three stems. No infestations of this size are 

currently known to exist but if they were found, no effects to fish or other aquatic organisms are anticipated to 

result from this activity.

Alternative 3

Potential effects to water quality from aquatic herbicide use are discussed in the Issue 18 (see Appendix G); this 

discussion focuses on potential effects to aquatic organisms themselves.

Pulling of invasive plants may inadvertently result in the removal of aquatic macroinvertebrates from aquatic 

habitat, particularly those species that live and forage in and around aquatic vegetation. This would result in 

temporary localized displacement or a reduction in population size. However, many individuals would escape or 

 35 Also called broadcast application.
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remain in undisturbed areas, and populations would quickly rebound. Therefore, effects to aquatic 

macroinvertebrate species diversity or populations would be negligible.

Placement of weed mats would result in a temporary (lasting up to a few years) conversion of the bottom 

substrate of portions of treated ponds from mud (the substrate parrot feather would likely be found in) to a nonnatural mat. This could result in less burrowing habitat for some species of macroinvertebrates. Over time, it is 

likely that additional fine sediments and decomposing organic materials would settle out and eventually cover the 

mats, and that eventually the treated areas would be indistinguishable from non-treated areas. Non-treated areas 

would remain adjacent to the installed mats, so these species would have other available habitats to utilize in the 

interim, resulting in negligible effects to macroinvertebrate species diversity or populations.

Mechanical methods, including diver assisted suction harvest (DASH) or tractors, would be used where removal of 

large portions of the root mass of the invasive is needed to treat the infestation. There would be a localized shortterm (several hours) disturbance to the area around the infestation, which would result in an increase in turbidity 

and disturbance to the bed of the channel or water body and surrounding vegetation (USDI 2010a:231). Over 

several hours, the sediment would resettle in close proximity to its source. Treating the sites while seasonally 

disconnected or during the period of lowest flow would reduce the amount of disturbance. Local populations of 

fish and aquatic organisms would disperse from the site but are then expected to return to the site to forage on 

recently uncovered macroinvertebrates. Areas proposed for treatment - slower water and off channel habitats or 

disconnected aquatic habitat - are less likely to have native fish species and therefore they are unlikely to be 

affected.

Effects to fish and other aquatic organisms from herbicides is based on the Risk Assessment information 

(summarized below in Table 3-6).

Table 3-6. Forest Service-Evaluated Herbicide Risk Categories for Aquatic Organisms (Aquatic Formulations)

Receptor 2,4-D Amine Fluridone Glyphosate Imazapyr Triclopyr

Typ1 Max1 Typ Max Typ Max Typ Max Typ Max

Flora

Accidental Acute Exposures

Macrophyte Susceptible H H H H H H H H H H

Macrophyte Tolerant 0 L H H 0 0 M H L M

Algae Susceptible L L H H H H L L M H

Algae Tolerant 0 0 H H 0 L 0 0 L M

Non-Accidental Acute Exposures

Macrophyte Susceptible M M M M L M M M H H

Macrophyte Tolerant 0 0 0 L 0 0 0 L 0 0

Algae Susceptible 0 0 0 L L L 0 0 0 L

Algae Tolerant 0 0 0 0 0 0 0 0 0 0

Chronic / Longer term Exposures

Macrophyte Susceptible M M L M L L M M M H

Macrophyte Tolerant 0 0 0 L 0 0 0 L 0 0

Algae Susceptible 0 0 0 L 0 L 0 0 0 0

Algae Tolerant 0 0 0 0 0 0 0 0 0 0

Fauna

Accidental Acute Exposures

Fish Susceptible 0 0 H H M H 0 L 0 L

Fish Tolerant 0 0 M M L L NE NE 0 0

Amphibian Susceptible 0 0 NE NE 0 0 NE NE 0 L

Amphibian Tolerant 0 0 NE NE 0 0 NE NE 0 L

Invertebrate Susceptible 0 0 H H M M NE NE 0 L

Invertebrate Tolerant 0 0 M M 0 0 0 0 0 0

Non-Accidental Acute Exposures

Fish Susceptible 0 0 0 0 0 L 0 0 0 0
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Receptor 2,4-D Amine Fluridone Glyphosate Imazapyr Triclopyr

Typ1 Max1 Typ Max Typ Max Typ Max Typ Max

Fish Tolerant 0 0 0 0 0 0 NE NE 0 0

Amphibian Susceptible 0 0 NE NE 0 0 NE NE 0 0

Amphibian Tolerant 0 0 NE NE 0 0 NE NE 0 0

Invertebrate Susceptible 0 0 0 0 0 0 NE NE 0 0

Invertebrate Tolerant 0 0 0 0 0 0 0 0 0 0

Chronic / Longer Term Exposures

Fish Susceptible 0 0 0 L 0 L 0 0 0 0

Fish Tolerant 0 0 0 0 0 0 0 0 0 0

Amphibian Susceptible NE NE NE NE 0 0 NE NE NE NE

Amphibian Tolerant NE NE NE NE 0 0 NE NE NE NE

Invertebrate Susceptible 0 0 0 0 0 0 NE NE 0 0

Invertebrate Tolerant 0 0 0 0 0 0 0 0 0 0

1. Typ = Typical application rate; and Max = Maximum application rate (see Table B-2, Herbicide Information, for typical and max applications 

rates. Application rates by species group can be found in the Treatment Key in Appendix C)

Risk categories: 0 = No risk (majority of Hazard Quotients < 1); L = Low risk (majority of Hazard Quotients >1 but < 10); M = Moderate risk 

(majority of Hazard Quotients > 10 but < 100); H = High risk (majority of Hazard Quotients > 100); and NE = Not evaluated. Risk categories are 

based on upper Hazard Quotient estimates. To determine risk for lower or central Hazard Quotient estimates, see the individual herbicide Risk 

Assessments. Risk categories are based on comparison to the Hazard Quotient of 1 for typical and maximum application rates.

Two factors determine the risk to aquatic organisms from use of herbicides: the toxicity of the chemical to 

individual organisms, and the likelihood organisms would be exposed to the chemical. Because aquatic herbicides 

would be applied directly to water or to plants floating on water, Risk Assessments focusing on the toxicity to 

organisms from direct exposure, including an accidental spill, are the appropriate scenarios for evaluating risk to 

aquatic flora and fauna from use of aquatic herbicides. 

The Risk Assessment for aquatic formulations of 2,4-D shows a hazard quotient of less than 0.5 (essentially no risk) 

under all scenarios analyzed with direct spray to fish and other aquatic fauna. Therefore, there is no potential that 

use of this herbicide would impart direct or indirect effects to these aquatic species.

The Risk Assessment for aquatic glyphosate shows a hazard quotient of less than one for typical non-accidental 

applications for susceptible fish and aquatic macroinvertebrates. However, under the accidental acute exposure 

scenario (e.g., a spill), the risk is elevated to 73 (moderate) at typical application rates, and 257 (high) at maximum 

application rates to fish and is within the moderate range for aquatic macroinvertebrates. However, the 

application rates (see Table C-3) would be less than 1.5 percent of the maximum rate and only 5 percent of the 

typical rate analyzed by the Risk Assessment. At these low concentrations, there would be no risk to aquatic fauna 

from glyphosate, unless a spill of concentrated chemical occurred directly in water, which would result in localized 

impacts to aquatic organisms. Standard Operating Procedures such as mixing and loading in areas where spill 

would not contaminate waterbodies would minimize or eliminate the risk of such a spill. Given the small area to be 

treated in any given year, and lack of direct risk to fish and other aquatic organisms, any potential future use of 

glyphosate as currently allowed would not directly effect fish or aquatic insects.

The Risk Assessment for the aquatic formulation of triclopyr shows no risk to any aquatic organisms under all 

scenarios, except for the accidental acute exposure scenario calculated for maximum rates of application (10 lbs. / 

acre; see Table B-2, Herbicide Information for typical and maximum application rates for each herbicide), which has 

low risk to susceptible fish and invertebrates (see Table 3-6 ). As shown in Appendix C, proposed application rates 

of triclopyr range from 0.6 to 2 lbs. / acre; therefore, there would be no risk to any aquatic fauna from use of this 

herbicide as proposed in this EA. For imazapyr, there is a similar risk to fish as described for triclopyr: no risk under 

any scenarios except for a low risk at the maximum rate under acute accidental exposure.

The Risk Assessment of fluridone showed no risk to macroinvertebrates, a low risk to susceptible fish under 

chronic long-term exposure, and a high risk at typical rates of application from acute accidental exposure to both 

fish and insects. Application rates proposed for fluridone use under this alternative are very low (5 to 30 parts per 
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billion in water) and fluridone would only be used in closed aquatic habitats that are disconnected and do not flow 

into streams and only on an extremely limited basis (less than 1 percent of all anticipated future treatments). 

Standard Operating Procedures (applicable under all alternatives), such as conducting mixing and loading 

operations in areas where an accidental spill would not contaminate an aquatic body, would further reduce risk of 

exposure. Because treatments using fluridone would be limited, if ever used at all, and because concentrations 

would be so low, and because it would only be applied in habitats not occupied by Special Status fish, there is no 

potential that use of it, as described in this EA, would result in any direct or indirect effect to Special Status fish.

Currently there is 0.32 acre of parrot feather at three sites in Hult Pond (Table C-1) and 0.19 acre of yellow flag iris, 

on Kelly Creek (see Table C-14). Given the limited number of known sites, the potential future herbicide 

treatments in aquatic habitat would be uncommon and less than two to three acres per year. Treatments would 

occur during periods of low flow or in seasonally disconnected or ponded habitats during a period of the year 

when this type of habitat would not be suitable for Special Status fish due to warm temperatures and low 

dissolved oxygen. Given that the typical amount of habitat treated by herbicides would be only two to three acres 

a year, and that the Risk Assessments found no risk to susceptible fish under application scenarios that represent 

how BLM would use herbicides, no adverse effects to Special Status fish would result from any potential future 

herbicide treatments directly in aquatic habitats.

Aquatic invasive plants can spread to infest an entire water body. While there are no currently known infestations 

on the District that meet this description, this analysis assumes that this will occur. In an area where invasive 

plants cover more than half the surface area of a waterbody, should all invasive plants in a closed aquatic 

environment (i.e., no flow in or out) die and decay at once, there would be potential for oxygen depletion, which 

could be lethal to gilled aquatic organisms. However, this would not affect Special Status fish since they would be 

very unlikely to be found in such locations during the summer months when treatments would occur. Special 

Status fish in the analysis area are dependent on cool, flowing, well-oxygenated water for survival, which are 

conditions not typically found in closed aquatic environments. The depletion of oxygen could result in localized 

die-offs of aquatic invertebrates. However, a required Project Design Features calls for phased treatments when 

treating aquatic weed populations. This would adequately limit the amount of decaying vegetation that could 

deplete oxygen levels for aquatic organisms. 

These invertebrate populations would quickly (within a few months) rebound by re-colonization from nearby 

source populations (Anderson 1992) through insect drift and dispersal mechanisms once the disconnected habitats 

were re-connected to adjacent aquatic habitats in the fall / winter. The temporary loss of vegetation would change 

the nature of the aquatic habitat. However, this would not have any meaningful effect on native fauna since the 

amount of area treated any given year would be less than 1/100th of one percent of all available aquatic habitat

across the District. Furthermore, these areas are not representative of natural habitat occupied by native 

salmonids. In Hult Pond, for example, the species present are primarily non-native game fish, bass, and bluegill. As 

the loss of habitat would be so small, it would be inconsequential to these nonnative species as well, and would 

not appreciably benefit native aquatic fauna. 

Indirectly, aquatic habitat would be improved in the long term at these localized spots, as removal of the invasive 

plant species could allow for colonization by native plant species. However, these effects would occur on such a 

small scale as to be inconsequential at the District-level in the short-term to populations of both native and 

nonnative plant species. Overall, treatments of currently small infestations of aquatic invasive plants would benefit 

fish and aquatic organisms by controlling existing invasive plant species and preventing future spread that has the 

potential to degrade large areas of habitat.

Selection and implementation of Alternative 3 would essentially mimic a localized drought event by temporarily 

increasing the amount of habitat disturbance, on less than three acres of disconnected aquatic habitat annually. 

This could potentially result in localized reductions in the number of aquatic macroinvertebrates for a few months 

by a small fraction of a percent relative to the No Action Alternative. This disturbance would be well within the 
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range of natural variability and would have much less impact on aquatic invertebrate populations than episodic 

drought and flood events, with which these aquatic organisms have evolved.

Summary of Effects

Table 3-7. Summary of Effects (Issue 2)

Alternative Direct Effects Indirect Effects 

No Action 

Alternative

and 

Alternative 2

There would be no application of herbicide directly to 

aquatic habitats, so no direct effects would occur to 

aquatic species or their habitats. If manual methods were 

used on one to three stems of an emergent weed, no 

effects are expected to fish or other aquatic organisms.

In the long term, invasive aquatic plants would 

continue to spread at 12 percent annually, to 

detriment of aquatic habitats and organisms. 

Alternative 3

Aquatic vegetation would be directly killed by herbicide 

treatments in water. This minor localized effect would 

impact less than 3 acres of aquatic habitat annually. No 

direct effects to aquatic fauna are anticipated to result. No 

effects to aquatic fauna are anticipated to result from nonherbicide treatments.

Minor localized indirect effects to 

macroinvertebrate assemblages in disconnected 

habitats could result from depleted dissolved 

oxygen from decaying vegetation. Re-colonization 

from adjacent untreated areas would begin to 

occur following treatments when aquatic habitats 

become re-connected. 

Cumulative Effects

Under the No Action Alternative and Alternative 2, there would be no direct or indirect effects from invasive plant

treatments to any aquatic organisms or aquatic habitat, and thus no cumulative effects are expected. Under 

Alternative 3, there would be no direct or indirect effects to native fish, but there would be direct effects to 

treated aquatic vegetation, which could in turn lead to indirect adverse effects to aquatic macroinvertebrates or 

habitat for aquatic organisms. 

Under all alternatives, other perturbations to aquatic habitat are expected to continue (as described under the 

Affected Environment section). Some of these perturbations impact water quality and habitat, and have led to 

shifts in macroinvertebrate assemblages. Excess sediment resulting from roads and ditch lines, instream mining, 

grazing, and other anthropomorphic disturbances has buried coarse gravel substrates in some stream systems. 

Elevated stream temperatures and reduced dissolved oxygen content from water withdrawals and clearing of 

riparian vegetation on private residential and agricultural lands has also degraded water quality and aquatic

habitat of stream reaches to varying degrees across the District. These types of disturbances have led to reductions 

in numbers and diversity of macroinvertebrate populations in some areas. These disturbances are chronic in 

nature and can persist for very long time periods (decades). Natural disturbance mechanisms such as floods, 

landslides, and droughts also episodically affect fish and macroinvertebrates, and can potentially result in local 

extirpations (e.g., a drought event that results in the desiccation of a stream or off-channel ponded habitat 

feature). However, these events are short duration, typically lasting less than a few months, and once conditions 

change, aquatic insects are known to be able to rapidly re-colonize and populations would re-bound in a very short 

time (within weeks to several months in most cases)(Benoit et al. 1998, Mackay 1992). 

In addition to effects described under Alternative 3, reasonably foreseeable future actions that would affect fish 

and aquatic organisms include routine fish passage and habitat restoration projects implemented as directed 

under the Northwestern and Coastal Oregon Resource Management Plan. These projects include the tipping, 

falling, and placing of whole trees and logs along with boulders to create spawning, resting, and rearing habitat for 

both anadromous and resident fish. These projects result in short-term, localized sediment pulses occurring during 

summer when juveniles are rearing in freshwater streams. Fish generally avoid sediment and associated turbidity 

by moving downstream or into side channels. Additional stress can result from disturbance, but effects are still 

expected to be negligible. Any accumulated fine sediment is routed through the system during the first higher fall 

flows.
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The BLM is in the preparation and planning stages of an environmental analysis addressing the safety of the dam at 

Hult Pond. This analysis may result in modifications to the dam site that would improve fish passage but would 

result in sediment routing downstream reducing the quality of spawning habitat in Lake Creek. Over a period of 

several years, any accumulated sediment would be routed through the system and gravel substrate would return 

to pre-project levels. If the dam is removed, it is likely that gravel stored in the pond substrate would also be 

carried downstream adding to the amount of spawning habitat downstream.

Issue 3: How would the alternatives affect the cost of invasive plant 

control?

Analytical Methods

As previously described in the analysis for the Oregon FEIS (USDI 2010a:338-343), costs are arguably not a 

potential effect on the human environment and are not required by NEPA. However, an analysis of how 

implementation costs change between the alternatives informs decision making. BLM policy specifies that 

management actions having a high likelihood of improving resource conditions for relatively small expenditures of 

time and money should receive relatively higher priority (USDI 2005:34).

Table 3-8. Direct Costs of Invasive Plant Treatments, by Gross Acre1

The costs presented in this section are in 2018 dollars. 

Costs listed here include equipment, materials 

(including herbicides36), wages, and contract costs; 

they do not include program planning (e.g., NEPA or 

the creation of Annual Treatment Plans). As shown in 

Table 3-8, the direct cost of treating an acre of 

invasive plants varies by method and by density of 

infestation. 

Density levels are defined as follows:

• Low concentrations consist of a few scattered 

plants, patches, clumps, or concentrations, 

generally less than 20 percent ground coverage 

within each treatment site.

• Medium concentrations consist of many plants, 

patches, clumps, or concentrations of specified 

species that have approximately 21 to 59 percent 

ground coverage within each treatment site.

• High concentrations consist of large, dense, 

heavy, concentrations of the specified species that have 60 to 100 percent ground coverage within each 

treatment site with only a few or occasional open areas.

Manual treatments range from $65 / acre (low density, pull and scatter invasive plants) to $380 (high density pull 

and bag invasive plants). Herbicide treatments are slightly less; herbicide spot spray of low-density plants is $58 / 

acre and herbicide wicking / wiping application of high-density plants is $270. Treatments of low-density 

infestations varies from $58 to $95 an acre, with the $95 / acre figure including manually pulling plants and then 

 36 The cost of the herbicide product may vary; however, with the exception of fluridone, the difference in costs are accounted 

for in Table 3-8. As shown in the Treatment Key (see Appendix C), fluridone would be used less than one percent of the time 

when aquatic species are treated, and there are only 0.32 acres of invasive plant infestation in the aquatic species group. 

Activity Density Cost

Herbicide Spot Spray Low $58.00

Manual Pull & Pile Low $65.00

Manual Pull & Scatter Low $65.00

Herbicide Spot Spray Medium $86.00

Herbicide Wicking/Wiping Application Low $88.00

Manual Pull & Bag Low $95.00

Manual Pull & Scatter Medium $145.00

Herbicide Wicking/Wiping Application Medium $150.00

Manual Pull & Pile Medium $165.00

Herbicide Spot Spray High $194.00

Manual Pull & Bag Medium $200.00

Herbicide Wicking/Wiping Application High $270.00

Manual Pull & Pile High $270.00

Manual Pull & Scatter High $270.00

Manual Pull & Bag High $380.00

1. Costs based on recent District contracts for invasive plant control 

projects.
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bagging them. Treatments of a high-density acre would range from $194 (herbicide spot spray) to $380 (manually 

pull and bag invasive plants).

The BLM plans to treat approximately 3,000 acres annually and for analysis purposes, the BLM assumes that the 

average gross acre infested with invasive plants has 25 percent coverage: a medium density acre. As described in 

Issue 1, invasive plant control treatments are not 100 percent effective at controlling invasive plant infestations on 

the first try. Under all alternatives, some level of retreatment would be necessary to achieve complete control. The 

amount of retreatment necessary is a function of how effective the prior treatment is. It is most appropriate to 

look at cost per effectively treated acres, because the overarching objective is to control invasive plants and 

prevent their spread.

Indirect costs are not analyzed in detail. As described in the Oregon FEIS, it is difficult to assess the monetary value 

for many of the resource values obtained from public lands (USDI 2010a:338). However, Issue 23 in this EA 

describes the negative effects in qualitative terms. A recent study estimated an annual loss of $83.5 million to the 

State's economy from 25 noxious weed species (ODA 2014). The indirect costs of the treatment of invasive plants 

would include program planning (e.g., the creation of Annual Treatment Plans, training, or management of the 

program), but it is not expected that additional costs would result from the selection of either action alternative. 

Public scoping comments raised the concern that herbicide use could lead to increased indirect costs related to 

medical bills, but this analysis did not indicate risk to human health from the use of herbicides (see Issues 11-14).

Treatments Planned Related to the Issue

Under the No Action Alternative, approximately 15 percent of invasive plant treatments would be with herbicides and 

85 percent would be with manual methods. Under the action alternatives, 25 percent of the treatments would be 

spot treatments with herbicides and 75 percent would be with manual methods. Herbicide treatments would be spot 

treatments 95 percent of the time.

Environmental Consequences

Costs shown in Table 3-8 reflect that contractors do the majority of the treatments on the District. Some treatments 

are done by volunteers or in coordination with other agencies and these costs are negligible, unknown, or would be 

borne by other agencies. Table 3-9 shows the average direct cost of invasive plant treatments.

Table 3-9. Average Direct Cost of Treatments (Annual)

Acres Treated Cost / Acre1 No Action Alternative Alternatives 2 and 3

Acres Total Cost Acres Total Cost 

Manually (contractor) $170 2,450 $416,500 2,150 $365,500

Manually (other) $0 100 $0 100 $0

With herbicides $86 450 $38,700 750 $64,500

Total $152 (No Action)

$143 (Alts. 2 and 3) 3,000 $455,200 3,000 $430,000

1. Assuming medium density and an average manual treatment cost.

As shown in Table 3-10 costs per effectively treated acre are 37 percent less under the action alternatives when

compared to the No Action Alternative. Similarly, the Oregon FEIS found that costs on west side districts (including 

Northwest Oregon) under Alternative 3 (similar to the action alternatives in this EA) would be reduced by 31 

percent, when compared to the No Action Alternative (USDI 2010a:78,340).
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Table 3-10. Costs of Effectively Treated Acre, by Alternative

No Action Alternative

The cost of implementing treatments under the No 

Action Alternative would be $455,200 a year, or 

$152 an acre. Treatments are estimated to be 30 to 

70 percent effective, so treatment cost per 

effectively treated acre is $301 (see Table 3-10).

Alternatives 2 and 3

The cost of implementing treatments under the No Action Alternative would be $430,000 a year, or $143 an acre. 

Treatments are estimated to be 60 to 80 percent effective, so treatment cost per effectively treated acre is $191

(see Table 3-10).

Cumulative Effects

Management of invasive plants affects the costs of managing BLM-administered lands. Increased operating costs 

due to invasive plant management may result in direct or indirect transfer of costs to land management programs 

or users of BLM-administered lands. Invasive plant management may compete with other important land 

management needs, resulting in cost tradeoffs. However, invasive plant treatments would result in improvements 

in the condition of BLM resources and would lead to increases in commodity and non-commodity values, 

improving the goods, services, and uses provided by BLM-administered lands. Treatments would increase the 

quantity and quality of wildlife forage, reduce fire hazard, and reduce other negative effects from invasive plant 

spread. Improved recreation opportunities and reductions in risk of wildfires would benefit the economies of local 

communities, which are dependent on recreational opportunities and other natural resource-based businesses.

No Action 

Alternative

Alternative

s 2 and 3

Cost per acre $152 $143

Cost per year $455,200 $430,000

Acres treated annually 3,000 3,000

Effectiveness of treatments 30%-70%1 60%-80%1

Acres effectively treated 1,510 2,252

Cost per effectively treated acre $301 $191

1. Varies by geographic area and/or species. See Issue 1 for more detail.
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Consultation and Coordination

The EA has been made available for a 30-day comment period.

List of Preparers

Core Team

Northwest Oregon

Team Lead and District Botanist and Invasive Plant Coordinator Claire Hibler

Field Office Botanist and Invasive Plant Coordinator Heidi Christensen 

Planning and Environmental Coordinator Panchita Paulete

Management Representative and Tillamook Assistant Field Manager Rachel Showalter 

GIS Specialist Jay Ruegger 

Oregon State Office

Project Manager and Oregon State Office Invasive Plant Coordinator Erin McConnell

Planner Leslie Frewing

Planner Richard Hardt

GIS Specialist Maria Fiorella

Denton and Denton Environmental (Contractor) Christi Denton

Denton and Denton Environmental (Contractor) Carolyn Sharp

Other Specialists (all Northwest Oregon District unless otherwise specified)

Wildlife Biologist John DeLuca 

Fuels Management Jessica Gallimore 

Ecologist (Plant Conservation Program) Patricia Johnston 

Recreation Traci Meredith 

Hydrologist Jonas Parker

Cartographer Gabriel Rousseau (Oregon State Office)

Fish Biologist Cory Sipher 

Soil Scientist Marissa Theve 

Archaeologist Heather Ulrich 

Reviewers

Thanks to the Botany Working Group (Teresa Coble, Terry Fennell, Douglas Goldenberg, Ian Grinter, Molly 

Widmer), Terry Godin, Katy Coddington, Robert Peffer, Sharon Klein, Whitney Wirthlin, and Sarah Bickford in the 

Northwest Oregon District Office and Mike Brown, Angel Dawson, Lee Folliard, Kirstin Heins, Bruce Hollen, Robert 

Hopper, Zachary Jarrett, Dave Johnson, Mike Kinsey, Scott Lightcap, Jerry Magee, Kristin Martine, Mark 

Mousseaux, and Leanne Mruzik in the Oregon State Office.

Review Opportunity

The EA and Finding of No Significant Impact (FONSI) were made available for a 30-day review period (November

2018) on BLM’s ePlanning website. Agencies, Native American Tribes, and interested members of the public were 

notified of the availability of the EA and FONSI for review. The mailing list is contained in the project record file.
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Glossary

Absorption: The process by which one substance, such as a solid or liquid, takes up another substance, such as a 

liquid or gas, through minute pores or spaces between its molecules. See also Adsorption.

Acetolactate synthase (ALS): A plant enzyme that facilitates the development of amino acids needed for plant 

growth.

Acetolactate synthase (ALS)-inhibitor: An herbicide that starves plants by reducing ALS. In this EA, the ALSinhibitors include four sulfonylureas (chlorsulfuron, metsulfuron methyl, rimsulfuron, and sulfometuron methyl) 

and two imidazolinones (imazapic and imazapyr).

Acid equivalent (a.e.): That portion of a formulation that theoretically could be converted back to the 

corresponding or parent acid. Or, the theoretical yield of parent acid from an active ingredient that has been 

formulated as a derivative (esters, salts, and amines are examples of derivatives).

Active ingredient (a.i.): The ingredient in an herbicide that prevents, destroys, repels, desiccates, or otherwise 

controls the target plant (e.g., glyphosate is the active ingredient in the product RoundUp).

Acute effect: An adverse effect on any living organism in which symptoms develop rapidly and often subside after 

the exposure stops.

Acute toxicity: The quality or potential of a substance to cause injury or illness shortly after exposure through a 

single or short-term exposure.

Adjuvant: A chemical that is added to the pesticide formulation to enhance the toxicity or effectiveness of the 

active ingredient or to make the active ingredient easier to handle or apply.

Administrative site: A reservation of public land for use as a site for a public building or other administrative 

facility. On BLM-administered lands in Oregon, this may include seasonal fire stations, rock quarries, bulk material 

and equipment storage areas, seed orchards, BLM-administered airstrips and helipads, BLM range improvements 

and water source developments, sanitary systems, BLM communication sites, remote automated weather stations, 

etc.

Adsorption: 1) The adhesion of substances to the surface of solids or liquids. 2) The attraction of ions of 

compounds to the surface of solids or liquids. See also Absorption.

Aerobic: Life or processes that require, or are not destroyed by, the presence of oxygen (also see anaerobic).

Affected environment: Existing biological, physical, social, and economic conditions of an area subject to change, 

both directly and indirectly, as the result of a proposed human action.

Air quality: The composition of air with respect to quantities of pollution therein. Used most frequently in 

connection with “standards” of maximum acceptable pollutant concentrations.

Anadromous fish: Fish that mature in the sea and swim up freshwater rivers and streams to spawn. Examples 

include salmon, steelhead, and sea-run cutthroat trout. See also Resident fish.

Anaerobic: Life or processes, such as the breakdown of organic contaminants by microorganisms, which take place 

without oxygen. Anaerobic, or saturated soils, are general found in areas with a high water table.
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Aquatic: Growing, living in, frequenting, or taking place in water; used to indicate habitat, vegetation, or wildlife in 

water.

Area of Critical Environmental Concern (ACEC): Lands where special management attention is needed to protect 

and prevent irreparable damage to important historic, cultural, or scenic values, fish and wildlife resources, or 

other natural systems or processes or to protect life and provide safety from natural hazards.

Bioaccumulation: The process of a plant or animal selectively taking in or storing a persistent substance. Over 

time, a higher concentration of the substance is found in the organism than in the organism’s environment.

Biological assessment: Information prepared by a Federal agency to determine whether a proposed action is likely 

to: (1) adversely affect listed species or designated critical habitat; (2) jeopardize the continued existence of 

species that are proposed for listing; or (3) adversely modify proposed critical habitat.

Biological control: The use of non-native agents including invertebrate parasites and predators (usually insects, 

mites, and nematodes), and plant pathogens to reduce populations of invasive plants. Also called biocontrol or 

biological control agent.

Boom (herbicide spray): A tubular device that conducts an herbicide mixture from a tank to a series of spray 

nozzles designed to deliver equal amounts across a bar. Usually mounted to a truck, or behind a tractor or allterrain vehicle oriented perpendicular to the direction of travel.

Broadcast treatment or application: An application of an herbicide that uniformly covers an entire area.

Buffer: A space or distance left between the application and a non-target area.

Chronic exposure: Exposures that extend over a long period. Chronic exposure studies are used to evaluate the 

carcinogenic potential of chemicals and other long-term health effects.

Chronic toxicity: The ability of a substance or mixture of substances to cause harmful effects over an extended 

period, usually upon repeated or continuous exposure sometimes lasting for the entire life of the exposed 

organism.

Clay: As defined by the U.S. Department of Agriculture (USDA) soil texture classification system, soil particles 

smaller than 0.002 mm in diameter. Fine textured sediment, with particles smaller than silt (USDA 2017).

Conservation Measures: Measures adopted with the 2007 Vegetation Treatments using Herbicides on BLM Lands 

in 17 Western States Biological Assessment and the 2016 Vegetation Treatments using Aminopyralid, Fluroxypyr, 

and Rimsulfuron to prevent or reduce herbicide effects to federally listed species. A Mitigation Measure adopted 

with the 2007 and 2016 PEISs also applies these measures to any species in the Special Status Species Program. 

These measures include (but are not limited to) herbicide-by-herbicide buffer distances from Special Status 

species, dependent on taxa and application method.

Consultation: Exchange of information and interactive discussion; usually refers to consultation mandated by 

statute or regulation that has prescribed parties, procedures, and timelines (e.g., Consultation under National 

Environmental Policy Act or Section 7 of the Endangered Species Act, or consultation with Tribes under Section 106 

of the National Historic Preservation Act).

Control: Eradicating, suppressing, or reducing vegetation.
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Critical habitat: 1) Specific areas within a species’ habitat that are critically important to its life functions; 2) an 

area designated by the U.S. Fish and Wildlife Service under rule-making as being critical to the needs of a federally 

listed species, and which then carries special protection and consultation requirements.

Cultural resources: Nonrenewable evidence of human occupation or activity as seen in any area, site, building, 

structure, artifact, ruin, object, work of art, architecture, or natural feature, which was important in human history 

at the national, state, or local level.

Cumulative effect: The effect that results from identified actions when they are added to other past, present, and 

reasonably foreseeable future actions regardless of who undertakes such other actions. Cumulative effects can 

result from individually minor but collectively significant actions taking place over a period of time.

Degradates: Compounds resulting from degradation.

Drift: That part of a sprayed herbicide that is moved from the target area by wind while it is still airborne.

Ecological amplitude: The limits of environmental conditions within which an organism can live and function.

Effect: Change resulting from a proposed action. Direct effects are caused by the action and occur at the same 

time and place, while indirect effects are caused by the action but are later in time, further removed in distance, or 

secondary. Effect and impact are synonymous as used in this document.

Endangered species: Any species listed under the Endangered Species Act as being in danger of extinction 

throughout all or a significant portion of its range.

Endangered Species Act: A law passed in 1973 to conserve species of wildlife and plants determined by the 

Director of the U.S. Fish and Wildlife Service or the National Marine Fisheries Service to be endangered or 

threatened with extinction in all or a significant portion of its range. Among other measures, the Endangered 

Species Act requires all Federal agencies to conserve these species and consult with the U.S. Fish and Wildlife 

Service or National Marine Fisheries Service on Federal actions that may affect these species or their designated 

critical habitat.

Endocrine: Relating to several glands that secrete hormones or products directly into the bloodstream.

Environmental assessment (EA): A public document that serves to document an examination of the potential 

environmental effects of a proposed project, and from that, documents whether to prepare an environmental 

impact statement or a finding of no significant impact.

Eradication: Removal or elimination of a population

Erosion: The wearing away of the land surface by running water, wind, ice, or other geological agents.

Fate: The course of an applied herbicide in an ecosystem or biological system, including metabolism, microbial 

degradation, leaching, and photodecomposition.

Federal Land Policy and Management Act of 1976 (FLPMA): Public Law 94-579. Provides the majority of the BLM’s 

legislated authority, direction, policy, and basic management guidance.

Federally listed: Species listed as threatened or endangered under the Endangered Species Act.

Forage: Vegetation eaten by animals, especially grazing and browsing animals.
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Forb: Broad-leaved herbaceous plant.

Formulation: The commercial mixture of an herbicide that includes both the active and inactive (inert) ingredients.

Fungi: Molds, mildews, yeasts, mushrooms, and puffballs, a group of organisms that lack chlorophyll and therefore 

are not photosynthetic.

Gastropod: A class of mollusks typically having a one-piece coiled shell and flattened muscular foot with a head 

bearing stalked eyes; includes snails, slugs, limpets, and cowries.

Gross infested area or treatment area: An area of land occupied by one or more invasive plant species; the area of 

land defined by drawing a line around the general perimeter of the infestation, not the canopy cover of the plants; 

the gross area of a logical treatment unit. May contain large parcels of land that are not occupied by the weed.

Groundwater: Subsurface water that is in the zone of saturation; the top surface of the groundwater is the “water 

table”; source of water for wells, seeps, and springs.

Groundwater contaminant: Chemical detected in ground waters. Does not necessarily infer levels are toxic or 

harmful.

Groundwater transmissivity: The rate at which groundwater flows horizontally through an aquifer.

Habitat: The natural environment of a plant or animal, including all biotic, climatic, and soil conditions, or other 

environmental influences affecting living conditions; the place where an organism lives.

Half-life: The amount of time required for half of a compound to degrade.

Hazard quotient (HQ): The ratio of the estimated level of exposure to a specific substance from a specific pesticide 

application to the reference dose (RfD) for that substance, or to some other index of acceptable exposure or 

toxicity. An HQ less than or equal to 1 is presumed to indicate an acceptably low level of risk for that specific 

application. Analogous to BLM risk quotient.

Herbicide: A pesticide used to control, suppress, or kill vegetation, or severely interrupt normal growth processes.

Herbicide resistance: Naturally occurring heritable characteristics that allow individual invasive plants to survive 

and reproduce, producing a population, over time, in which the majority of the plants of the weed species have the 

resistant characteristics.

Hydrologic: The properties, distribution, and effects of water on the earth's surface, in the soil and underlying 

rocks, and in the atmosphere.

Hydrolysis: The chemical breakdown of a compound due to reaction with water.

Inert ingredients: Ingredients that are added to the commercial product (formulation) of an herbicide and are not 

herbicidally active.

Infested: An area having one or more of the subject invasive plant species – either plants or plant pathogens. 

Infested areas are not necessarily 100 percent infested.

Interagency Special Status / Sensitive Species Program (ISSSSP): The BLM and Forest Service collaboration to 

coordinate record keeping and other management of the Bureau Special Status and Forest Service Sensitive 

species programs. See also Special Status species.
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Intermittent stream: Any non-permanent flowing drainage feature having a definable channel and evidence of 

annual scour or deposition. This includes what are sometimes referred to as ephemeral streams if they meet these 

two criteria.

Invasive plants: Non-native aggressive plants with the potential to cause significant damage to native ecosystems, 

cause significant economic losses, or both. This EA and the Oregon FEIS definition differs from the 2007 PEIS 

definition by not including species native to the ecosystem under consideration.

Issue: A matter of controversy, dispute, or general concern over resource management activities or land uses.

Label: All printed material attached to or part of the pesticide container, and which contains instructions for the 

legal application of the pesticide.

LC50 (median lethal concentration): A concentration of a chemical in air or water to which exposure for a specific 

length of time is expected to cause death in 50 percent of a defined experimental animal population.

LD50 (median lethal dose): The dose of a chemical calculated to cause death in 50 percent of a defined 

experimental animal population over a specified observation period. The observation period is typically 14 days.

Leaching: The movement of chemicals through the soil by water; may also refer to the movement of herbicides out 

of leaves, stems, or roots into the air or soil.

Level of concern (LOC): The concentration or other estimate of exposure above which there may be effects.

Listed species: Formally listed as a threatened or endangered species under the Endangered Species Act. 

Designations are made by the U.S. Fish and Wildlife Service or National Marine Fisheries Service.

Lowest observed adverse effect level (LOAEL): The lowest dose of a chemical in a study, or group of studies, that 

produces statistically or biologically significant increases in frequency or severity of adverse effects between the 

exposed and control populations.

Maximum application rate: The maximum application rate analyzed in risk scenarios in the Risk Assessments. The 

rate may be the same as the rate on the label of the formulated product, but in certain cases, the maximum 

application rate is lower. 

Mechanical control: The use of any mechanized approach to control or eliminate invasive plants (e.g., mowing, 

weed whipping, or cutting with a chainsaw).

Mitigation: Actions that would: 1) avoid an impact altogether by not taking a certain action or parts of an action; 2) 

minimize an impact by limiting the degree or magnitude of the action and its implementation; 3) rectify an impact 

by repairing, rehabilitating, or restoring the affected environment; 4) reduce or eliminate an impact over time by 

preserving and maintaining operations during the life of the action; or, 5) compensate for an impact by replacing 

or providing substitute resources or environments.

Mitigation Measures: Measures adopted with the 2007 Vegetation Treatments using Herbicides on BLM Lands in 

17 Western States EIS and Record of Decision, the 2016 Vegetation Treatments using Aminopyralid, Fluroxypyr, 

and Rimsulfuron PEIS and Record of Decision, or the 2010 Vegetation Treatments using Herbicides on BLM Lands in 

Oregon FEIS and Record of Decision to prevent or reduce herbicide effects. These measures all apply to this 

analysis and are included in Appendix D.

Monoculture: A population dominated by a single species; a prevailing culture marked by homogeneity.
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Monitoring: The orderly collection, analysis, and interpretation of resource data to evaluate progress toward 

meeting management objectives.

Nematode: Any of a phylum (Nematoda or Nemata) of elongated cylindrical worms parasitic in animals or plants 

or free-living in soil or water —also called roundworm.

No Action Alternative: The most likely condition to exist in the future if current management direction were to 

continue unchanged.

No observed adverse effect level (NOAEL): The exposure level at which there are no statistically or biologically 

significant differences in the frequency or severity of any adverse effect between the exposed and control 

populations.

Non-selective herbicide: An herbicide that is generally toxic to plants without regard to species or group.

Non-target: Any organism that is not the objective of a control treatment.

Noxious weed: A subset of invasive plants that are State, county, or federally listed as injurious to public health, 

agriculture, recreation, wildlife, or any public or private property.

Particulate matter (PM): A complex mixture consisting of varying combinations of dry solid fragments, solid cores 

with liquid coatings, and small droplets of liquid. These tiny particles vary greatly in shape, size, and chemical 

composition, and can be made up of many different materials such as metals, soot, soil, and dust.

Pathogen: Any disease-producing agent, especially a virus, bacterium, or other microorganism.

Perennial: A plant with a life cycle lasting more than two years; a stream that flows year round.

Persistence: The length of time a compound, once introduced into the environment, stays there.

Pesticide: Any substance used for controlling, preventing, destroying, repelling, or mitigating any pest. Includes 

fungicides, herbicides, fumigants, insecticides, nematicides, rodenticides, desiccants, defoliants, plant growth 

regulators, and so forth. Any material used in this manner is a pesticide and must be registered as such, even if it 

has other non-pesticide uses.

pH: A measure of how acidic or alkaline (basic) a solution is on a scale of 0 to 14 with 0 being very acidic, 14 being 

very alkaline, and 7 being neutral. The abbreviation stands for the potential of hydrogen.

Photo degradation: The photochemical transformation of a molecule into lower molecular weight fragments, 

usually in an oxidation process. This term is widely used in the destruction (oxidation) of pollutants by ultravioletbased processes.

Photolysis: The chemical breakdown of a compound due to reaction with light.

Point of Diversion (water): The geographic area from which water is diverted using infrastructure (works) and put 

to beneficial use. Examples of works include groundwater wells, water storage dams, diversion dams, dugouts, and 

pump sites along a surface water source.

Post-emergent (herbicide): Herbicide used to kill invasive plants after they have germinated and are growing.

Pre-emergent (herbicide): Herbicide applied to the soil to keep seeds from germinating.
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Prescribed fire: A wildland fire that burns under specified conditions and in a predetermined area, to produce the 

fire behavior and fire characteristics required to attain resource management objectives.

Prevention: To detect and ameliorate conditions that cause or favor the introduction, establishment, or spread of 

invasive organisms or conditions.

Project Design Features: Features included in this analysis to prevent adverse effects from invasive plant 

treatments under the action alternatives.

Propagule: A part of a plant, e.g., a bud, spore, or root fragment, capable of producing a new plant.

Proposed threatened or endangered species: Plant or animal species proposed by the U.S. Fish and Wildlife 

Service or National Marine Fisheries Service to be biologically appropriate for listing as threatened or endangered 

and that is published in the Federal Register. It is not a final designation. Proposed species are, at minimum, 

managed as Bureau Sensitive until a decision is made about Federal listing.

Protection Measures: Includes Standard Operating Procedures (from BLM manuals and handbooks), Mitigation 

Measures (adopted with the Records of Decision from the 2010 Oregon FEIS and 2007 and 2016 PEISs), Project 

Design Features (included in this EA), and Conservation Measures and Project Design Criteria (from listed species 

consultation) identified to protect resources from adverse effects from invasive plant treatments. See Appendix D, 

Protection Measures.

Rangeland: Land on which the native vegetation is predominantly grasses, grass-like plants, forbs, or shrubs; not 

forests.

Receptor: A biological entity such as a human, fish, plant, or invertebrate; used in the context of herbicide Risk 

Assessments and the organisms that are used to assess the potential affects of the herbicide.

Resident fish: Fish that spend their entire life in freshwater (e.g., bull trout) on or near a specific location.

Residue: Herbicide or its metabolites remaining in or on soil, water, plants, animals, or other surfaces.

Restricted Use Pesticide: A classification assigned by the EPA to prevent unreasonable adverse effects from a 

pesticide product. The classification restricts a product, or its uses, to use by a certified applicator. These 

herbicides are not available to the general public.

Resource Management Plan: Land use plans developed by BLM under the FLPMA; provides long-term (up to 20 

years) direction for the management of a particular area of land.

Revegetation: Establishing or re-establishing desirable plants where desirable plants are absent or of inadequate 

density, either by controlling site conditions (including the suppression of unwanted competition) so existing 

vegetation can reseed and spread, or by direct seeding or transplanting.

Right-of-way: A permit or an easement that authorizes the use of lands for certain specified purposes, such as the 

construction of forest access roads, gas pipelines, or power lines.

Riparian area: Those terrestrial areas where the vegetation complex and microclimate conditions are products of 

the combined presence and influence of perennial or intermittent water, associated high water tables, and soils 

that exhibit some wetness characteristics. Normally used to refer to the zone within which plants grow rooted in 

the water table of these rivers, streams, lakes, ponds, reservoirs, springs, marshes, seeps, bogs, and wet meadows.
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Riparian habitat: Areas adjacent to rivers and streams with a high density, diversity, and productivity of plant and 

animal species relative to nearby uplands.

Risk: The likelihood that a given exposure to an item or substance (e.g., herbicide dose) will produce illness or 

injury.

Runoff: Overland flow; the part of precipitation, as well as any other flow contributions that does not soak into soil 

or stay held on the site for evaporation or transpiration, but runs into streams.

Safety data sheet (SDS): A compilation of information required under the Occupational Safety and Health 

Administration Communication Standard on the identity of hazardous chemicals, health and physical hazards, 

exposure limits, and precautions.

Salmonids: Fishes of the family Salmonidae, including salmon, trout, chars, whitefish, ciscoes, and grayling.

Sand: As defined by the USDA soil texture classification system, individual rock or mineral fragments that range in 

diameter from 0.05 to 2 mm in diameter (USDA 2017).

Scoping: A process at the beginning of a NEPA analysis whereby the public is asked to provide oral or written 

comments about the scope of the analysis and the range of alternatives, to help ensure the analysis appropriately 

addresses potential effects on individuals, communities, and the environment.

Sediment: Unweathered geologic materials generally laid down by or within water bodies; the rocks, sand, mud, 

silt, and clay at the bottom and along the edge of lakes, streams, and oceans.

Selective herbicide: An herbicide designed to affect only certain groups or types of plants, leaving other tolerant 

plants unharmed.

Sensitive species (Bureau Sensitive): Native species designated by the BLM State Director as Sensitive because 

they are found on BLM-administered lands for which the BLM has the capability to significantly affect the 

conservation status of the species through management, and either: 1) There is information that a species has 

recently undergone, is undergoing, or is predicted to undergo a downward trend such that the viability of the 

species or a distinct population segment of the species is at risk across all or a significant portion of the species 

range, or 2) The species depends on ecological refugia or specialized or unique habitats on BLM-administered

lands, and there is evidence that such areas are threatened with alteration such that the continued viability of the 

species in that area would be at risk.

Significant: The description of an impact that exceeds a certain threshold level. Requires consideration of both 

context and intensity. The significance of an action must be analyzed in several contexts, such as society as a 

whole, and the affected region, interests, and locality. Intensity refers to the severity of effects, which should be 

weighed along with the likelihood of its occurrence. Determination of significance for effects is a management 

decision considering multiple factors, and not one made by technical specialists to indicate the quantity of effects 

are above or below some level.

Silt: As defined by the USDA soil texture classification system, individual mineral particles that range in diameter 

from between 0.002 and 0.05 mm in diameter (USDA 2017).

Site-specific: At the site, area, or project level.

Socioeconomic: Pertaining to, or signifying the combination or interaction of social and economic factors.

Sorption: The attachment of one particle to another; a general term, which includes adsorption and absorption.
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Special Status species: Federally listed threatened, endangered, proposed, or candidate species, and species 

managed as Sensitive species by the BLM.

Spot treatment: An application of an herbicide to a small selected area such as an individual plant, as opposed to a 

broadcast application.

Standard Operating Procedures: Procedures that would be followed by the BLM to ensure that risk to human 

health and the environment from treatment actions were kept to a minimum. See Appendix D. Since they originate 

from Manual and other direction, they may appear in resource management and other plans under other titles.

Subsistence: Customary and traditional uses of wild renewable resources (plants and animals) for food, shelter, 

fuel, clothing, tools, etc.

Sulfonylurea: A group of herbicides that interfere with acetolactate synthase (ALS), an enzyme needed for plant 

cell growth.

Surfactant: A material that improves the emulsifying, dispersing, spreading, wetting, droplet size, or other surfacemodifying properties of liquids.

Target species: A species (in this EA, a plant species) that is a target or goal of a treatment or control effort.

Targeted grazing: The carefully controlled grazing of livestock, such as cattle, sheep, or goats, to accomplish 

specific vegetation management objectives. Livestock can be used as a tool for improving land health by 

performing weed control and aiding in restoration projects.

Threatened species: A plant or animal species federally listed as threatened under the Endangered Species Act, 

and status defined as likely to become an endangered species throughout all or a significant portion of its range 

within the foreseeable future.

Toxicity: A characteristic of a substance that makes it injurious.

Traditional use areas (Native American plant gathering): Areas where Tribes continue to gather plant materials 

for food, basketry, and other traditional uses. These may or may not be treaty reserved rights or areas.

Transmissivity: See Groundwater Transmissivity.

Treaty rights: Tribal rights or interests reserved in treaties, by Native American Tribes for the use and benefit of 

their members. The uses include such activities as described in the respective treaty document. Only Congress may 

abolish or modify treaties or treaty rights.

Tribe: Term used to designate any Native American band, nation, or other organized group or community.

Typical rate or typical application rate: One of two application rates considered in many Risk Assessments (the 

other being maximum rate); a rate based upon a general summary of actual applications that have been made of 

the different formulations of a particular active ingredient on BLM-administered lands. Under some situations, this 

value may be higher or lower than what is going to be applied for a specific job. The rate of application of any 

pesticide is based upon several factors, including, but not limited to, the species to be controlled, the environment 

for which the application is to be made, the timing of the application, and other factors.

Uncertainty factor: A multiplier used in Risk Assessments to compensate for unknown risks due to limitations in 

the research.
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Volatilization: The conversion of a solid or liquid into a gas or vapor; evaporation of herbicide before they are 

bound to a plant or ground.

Watershed: The region draining into a river, stream, or body of water. When used in this EA, it refers to a 5th-field 

hydrologic unit. 

Weed: When not preceded by “noxious,” this term generally means invasive plants (including noxious weeds) in 

this EA. Its use in this EA is avoided except when it is used in citations and paraphrases of other documents, or is 

part of titles or common phrases. Within such documents, the intent is usually noxious weeds and other invasive 

plants.

Wetlands: An area that is saturated by surface or ground water with vegetation adapted for life under those soil 

conditions, as swamps, bogs, fens, marshes, and estuaries.

Wild and Scenic Rivers: Rivers designated in the National Wild and Scenic Rivers System that are classified in one 

of three categories (wild, scenic, or recreational), depending on the extent of development and accessibility along 

each section. In addition to being free flowing, these rivers and their immediate environments must possess at 

least one outstandingly remarkable value: scenic, recreational, geologic, fish and wildlife, historical, cultural, or 

other similar values.

Wilderness: Land designated by Congress as a component of the National Wilderness Preservation System.
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References

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activities affecting ESA-Listed animal and plant species and their designated or proposed critical 

habitat and designated essential fish habitat under MSA found in Oregon, Washington and parts of 

California, Idaho and Nevada. January 28.

USDI 1985 USDI Bureau of Land Management. 1985. Northwest Area Noxious Weed Control Program Final EIS. 

BLM Oregon State Office. Portland, OR.
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

References

65

Cited As Reference

USDI 1986 USDI Bureau of Land Management. 1986. Visual Resources Contrast Rating Manual Handbook H8431-1. Washington, DC.

USDI 1987a USDI Bureau of Land Management. 1987. Northwest Area Noxious Weed Control Program 

Supplemental EIS. BLM Oregon State Office. Portland, OR. 

USDI 1987b USDI Bureau of Land Management. 1987. Supplemental Record of Decision Northwest Area Noxious 

Weed Control Program. Washington, D. C.

USDI 1992a USDI Bureau of Land Management. 1992. Handbook 9011. Chemical Pest Control Handbook. 

USDI 1992b USDI Bureau of Land Management. 1992. Manual 9015. Integrated Weed Management. Release 9-

321. 

USDI 1993 USDI Bureau of Land Management. 1993. Sandy Wild and Scenic River and State Scenic Waterway 

Management Plan 

USDI 2005 USDI Bureau of Land Management. 2005. Handbook 1601-1. Land Use Planning Handbook. Release 1-

1693. 

USDI 2007a

USDI Bureau of Land Management. 2007. Vegetation Treatments using Herbicides on Bureau of Land 

Management Lands in 17 Western States Programmatic Environmental Impact Statement. 

https://eplanning.blm.gov/epl-frontoffice/eplanning/planAndProjectSite.do?methodName=dispatchToPatternPage¤tPageId=1035

92

USDI 2007b

USDI Bureau of Land Management. 2007. Vegetation Treatments using Herbicides on Bureau of Land 

Management Lands in 17 Western States Record of Decision. https://eplanning.blm.gov/epl-frontoffice/eplanning/planAndProjectSite.do?methodName=dispatchToPatternPage¤tPageId=1035

92

USDI 2007c USDI Bureau of Land Management. 2007. Vegetation Treatments on Bureau of Land Management 

Lands in 17 Western States. Biological Assessment BLM, Nevada State Office, Reno, NV.

USDI 2007d

USDI Bureau of Land Management. 2007. Vegetation Treatments on Bureau of Land Management 

Lands in 17 Western States. Final Programmatic Environmental Report. BLM, Nevada State Office, 

Reno, NV. https://eplanning.blm.gov/epl-frontoffice/eplanning/planAndProjectSite.do?methodName=dispatchToPatternPage¤tPageId=1035

92

USDI 2007e USDI 2007. Department of the Interior Departmental Manual. Part 517. Pesticides.

USDI 2008a

USDI Bureau of Land Management. 2008. BLM Handbook H1740-2 Integrated Vegetation 

Management. Washington D.C. 

https://www.blm.gov/sites/blm.gov/files/uploads/Media_Library_BLM_Policy_Handbook_H-1740-

2.pdf

USDI 2008b USDI Bureau of Land Management. 2008. BLM Manual 6840, Special Status Species Management. IM 

2009-039.

USDI 2008c

USDI Bureau of Land Management. 2008. BLM Handbook H-1790-2 National Environmental Policy Act 

Handbook. Washington D.C. https://www.ntc.blm.gov/krc/uploads/366/NEPAHandbook_H1790_508.pdf

USDI 2008d USDI Bureau of Land Management. 2008. Westside Salem Integrated Non-Native Plant Management 

Plan Environmental Assessment

USDI 2008e

USDI Fish and Wildlife Service. 2008. Birds of Conservation Concern 2008. United States Department 

of Interior, Fish and Wildlife Service, Division of Migratory Bird Management, Arlington, Virginia. 85 

pp.

USDI 2009 USDI Bureau of Land Management. 2009. Cascades Resource Area Invasive Non-Native Plant 

Management EA.

USDI 2010a

USDI Bureau of Land Management. 2010. Vegetation Treatments Using Herbicides on BLM Lands in 

Oregon Final Environmental Impact Statement. https://eplanning.blm.gov/epl-frontoffice/eplanning/planAndProjectSite.do?methodName=renderDefaultPlanOrProjectSite&projectId=7

0730&dctmId=0b0003e880df5615

USDI 2010b

USDI Bureau of Land Management. 2010. Vegetation Treatments Using Herbicides on BLM Lands in 

Oregon Record of Decision. https://eplanning.blm.gov/epl-frontoffice/eplanning/planAndProjectSite.do?methodName=renderDefaultPlanOrProjectSite&projectId=7

0730&dctmId=0b0003e880df5615

USDI 2010c USDI Bureau of Land Management. 2015. Marys Peak Resource Area Noxious Weed Control Utilizing 

Glyphosate EA
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

References

66

Cited As Reference

USDI 2010d USDI Bureau of Land Management. 2015. Marys Peak Resource Area Noxious Weed Control Utilizing 

Glyphosate Final Decision and Rationale.

USDI 2010e

USDI Fish and Wildlife Service. 2010. Recovery Plan for the Prairie Species of Western Oregon and 

Southwestern Oregon. Portland, OR.

https://www.fws.gov/oregonfwo/Species/PrairieSpecies/Documents/PrairieSpeciesFinalRecoveryPla

n.pdf

USDI 2011 USDI Bureau of Land Management. 2011. Oak Basin Restoration/RAC Project Upper Willamette 

Resource Area BLM Eugene District Environmental Assessment DOI-BLM-OR-E060-2011-0005-EA.

USDI 2013a

USDI Fish and Wildlife Service. 2013. Endangered Species Act - Section 7 Consultation Programmatic 

Biological Opinion for Aquatic Restoration Activities in the States of Oregon, Washington and portions 

of California, Idaho and Nevada (ARBO II). 

USDI 2013b

USDI Fish and Wildlife Service. 2013. Endangered and Threatened Wildlife and Plants; Designation of 

Critical Habitat for Taylor's Checkerspot Butterfly and Streak Horned Lark; Final Rule. Federal Register 

78(192):61506-61589.

USDI 2014a USDI Bureau of Land Management. 2014. Biological Assessment for the Resource Management Plan 

for the West Eugene Wetlands in Lane County, Oregon on the US BLM – Eugene District.

USDI 2014b USDI Fish and Wildlife Service. 2014c. Biological Opinion For The Resource Management Plan For The 

West Eugene Wetlands In Lane County, Oregon. FWS Reference Number OlEOFW00-2014-F-0139.

USDI 2015a

USDI Bureau of Land Management. 2015. Proposed Resource Management Plan and Final 

Environmental Impact Statement for the Bureau of Land Management West Eugene WetlandsF

Resource Management Plan. Eugene District.

USDI 2015b USDI Bureau of Land Management. 2015. Record of Decision and Resource Management Plan West 

Eugene Wetlands. Eugene District.

USDI 2015c

USDI Fish and Wildlife Service. 2015. Coastal Recovery Unit Implementation Plan for Bull trout 

(Salvelinus confluentus). Lacey, WA.

https://www.fws.gov/pacific/bulltrout/pdf/Final_Coastal_RUIP_092915.pdf

USDI 2016a USDI Bureau of Land Management. 2016. Final Programmatic Environmental Impact Statement for 

Vegetation Treatments Using Aminopyralid, Fluroxypyr, and Rimsulfuron. Washington Office

USDI 2016b USDI Bureau of Land Management. 2016. Record of Decision for Vegetation Treatments Using 

Aminopyralid, Fluroxypyr, and Rimsulfuron. Washington Office

USDI 2016c USDI Bureau of Land Management. 2016. Biological Assessment for Vegetation Treatments Using 

Aminopyralid, Fluroxypyr, and Rimsulfuron. Washington Office

USDI 2016d USDI Bureau of Land Management. 2016. Northwestern and Coastal Oregon Resource Management 

Plan and Record of Decision

USDI 2016e USDI Bureau of Land Management. 2016. Proposed Resource Management Plan / Final 

Environmental Impact Statement for Resource Management Plans for Western Oregon. 

USDI 2017 USDI 2017. Department of the Interior Departmental Manual. Part 524. Invasive Species 

Management.

USDI 2018 USDI Bureau of Land Management. 2018. Categorical Exclusion for Invasive Plant Control: Siuslaw 

Field Office and Upper Willamette Field Office

USEPA 2001 Environmental Protection Agency. 2001. Office of Pesticide Programs. General Principles for 

Performing Aggregate Exposure and Risk Assessments.

USEPA 2004 US Environmental Protection Agency 2004. Human Health Risk Assessment for 2,4-D.

USEPA 2007

US Environmental Protection Agency. 2007. Inert (other) Pesticide Ingredients in Pesticide Products -

Categorized List of Inert (other) Pesticide Ingredients (outdated). 

http://www.epa.gov/opprd001/inerts/oldlists.html

Vencill et al. 2002 Vencill, W.K. (ed). 2002. Herbicide Handbook, 8th ed. Weed Science Society of America, Lawrence, 

KS. 155-157.

Washington 

Department of Ecology 

2002

Washington Department of Ecology. 2002. Eurasian Watermilfoil Infested Lake Control Strategies. 

Eradication - Whole Lake Furidone Treatment (Aquatic Herbicide).

Woodward et al. 1997 Woodrow J.E., Seiber J.N., and Baker L.W. 1997. Correlation techniques for estimating pesticide 

volatilization flux and downwind concentrations. Environ. Sci. Technol. 31(2), 523–529.
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendices

67

Appendices

Appendix A: Invasive Plants on the District..................................................................................................... 72

Existing Invasive Plant Sites.....................................................................................................................................72

Spread from Existing Invasive Plant Sites................................................................................................................74

Potential New Invaders ...........................................................................................................................................75

Appendix B: Integrated Invasive Plant Management...................................................................................... 81

Prevention, Education, and Awareness...................................................................................................................81

Coordination and Cooperation................................................................................................................................82

Planning ...................................................................................................................................................................82

Prioritizing Areas for Treatment..........................................................................................................................82

Monitoring...............................................................................................................................................................84

Implementation Monitoring................................................................................................................................84

Effectiveness Monitoring.....................................................................................................................................84

Direct Control Methods...........................................................................................................................................85

Manual Treatment Methods ...............................................................................................................................85

Mechanical Treatment Methods.........................................................................................................................86

Competitive Seeding and Planting.......................................................................................................................87

Prescribed Fire.....................................................................................................................................................87

Biological Treatment Methods............................................................................................................................88

Herbicide Treatment Methods............................................................................................................................89

Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan......................................... 98

Appendix D: Protection Measures ................................................................................................................ 144

Project Design Features.........................................................................................................................................144

Special Status Species........................................................................................................................................144

Native Vegetation..............................................................................................................................................145

Wildlife...............................................................................................................................................................146

Fish / Riparian....................................................................................................................................................146

Traditional and Cultural Uses (Native American Interests) ...............................................................................146

Soil .....................................................................................................................................................................147

Standard Operating Procedures and Mitigation Measures...................................................................................147

General ..............................................................................................................................................................148

Land Use ............................................................................................................................................................150

Air Quality..........................................................................................................................................................150

Soil Resources....................................................................................................................................................151

Water Resources................................................................................................................................................152

Wetlands and Riparian Areas ............................................................................................................................153

Vegetation .........................................................................................................................................................153

Pollinators..........................................................................................................................................................155

Fish and Other Aquatic Species .........................................................................................................................155

Wildlife Resources.............................................................................................................................................156

Threatened and Endangered Species................................................................................................................157

Cultural Resources.............................................................................................................................................158

Paleontological Resources.................................................................................................................................159

Visual Resources................................................................................................................................................159

Wilderness and Other Special Areas..................................................................................................................160

Recreation..........................................................................................................................................................161
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

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68

Social and Economic Values...............................................................................................................................162

Rights-of-way.....................................................................................................................................................163

Human Health and Safety..................................................................................................................................163

Protection Measures for Federally Listed Species.................................................................................................165

Conservation Measures from the 2007 and 2016 PEISs Biological Assessments..............................................168

Project Design Criteria for Listed Species from ARBO II (NMFS 2013, USDI 2013a)..........................................180

Appendix E: Herbicides Formulations and Adjuvants ................................................................................... 188

Appendix F: Herbicide Risk Assessment Summaries..................................................................................... 204

EPA Labels..............................................................................................................................................................204

Risk Assessments...................................................................................................................................................205

Drift........................................................................................................................................................................206

High, Moderate, and Low Risk in BLM and Forest Service Risk Assessments........................................................207

BLM Ecological Risk Assessments......................................................................................................................207

BLM Human Health Risk Assessments (2007 and 2016)....................................................................................208

Forest Service Risk Assessments........................................................................................................................208

Uncertainty in the Risk Assessment Process .........................................................................................................209

Appendix G: Issues Not Analyzed in Detail.................................................................................................... 220

Issue 4 (Native Vegetation): What are the effects of invasive plant treatments on desirable plant communities 

and Special Status plants? .................................................................................................................................220

Issue 5 (Fungi): How would invasive plant treatments affect fungi?.................................................................222

Issue 6 (Wildlife): How would integrated invasive plant management affect wildlife of conservation concern?

...........................................................................................................................................................................222

Issue 7 (Birds): How would treatments affect birds that may use potential treatment areas, especially during 

the nesting season? ...........................................................................................................................................223

Issue 8 (Pollinators): How would herbicide treatments affect pollinators, especially Special Status pollinator 

species? .............................................................................................................................................................224

Issue 9 (Turtles): How would the treatment of aquatic invasive plants affect the western pond turtle and 

painted turtle?...................................................................................................................................................225

Issue 10 (Fish and Aquatic Organisms): What are the effects of terrestrial herbicide treatments along streams 

to fish and aquatic organisms?..........................................................................................................................226

Issue 11 (Human Health): What are the effects to human health from incidentally coming into contact with 

herbicides used on BLM-administered lands?...................................................................................................226

Issue 12 (Human Health): What are the hazards to workers treating invasive plants? ....................................230

Issue 13 (Human Health): What are effects to human health of mixing two or more herbicides? What are the 

effects from adjuvants and other ingredients mixed with herbicides? What are the effects from the 

degradates when herbicides break down?........................................................................................................231

Issue 14 (Human Health): What are effects to human health of using glyphosate, which a California court 

recently found to be cancer-causing, the International Agency for Research on Cancer (IARC) has declared a 

cancer hazard, and has been found in breakfast cereal? ..................................................................................232

Issue 15 (Human Health): What are the effects to human health from invasive plants (allergies, rashes, etc.)?

...........................................................................................................................................................................234

Issue 16 (Soil): How do herbicides detrimentally affect soils? ..........................................................................234

Issue 17 (Water): How do herbicides treating terrestrial weeds affect water quality, including ground and 

surface water used for domestic and municipal supply? ..................................................................................235

Issue 18 (Water): How do herbicide treatments of aquatic invasive plants affect water quality? ...................236

Issue 19 (Air): How would the alternatives affect air quality? ..........................................................................237

Issue 20 (Air): How would the alternatives affect climate change, including greenhouse gas emissions and 

carbon storage?.................................................................................................................................................238
Integrated Invasive Plant Management for the Northwest Oregon District

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Issue 21 (Traditional and Cultural Uses): How would the treatment of invasive plants affect plant resources 

used by Native Americans given that these plants (or their locations) may not be known by the BLM?.........238

Issue 22 (Environmental Justice): How would the use of herbicides affect minorities and low-income 

populations? ......................................................................................................................................................240

Issue 23 (Socioeconomics): What are the impacts to local timber production, forest products, agriculture, and 

recreation economies from the management of invasive plants in the Northwest Oregon District? ..............240

Issue 24 (Socioeconomics): What is the potential for herbicide contamination of yards, gardens, organic farms, 

vineyards, and bee hives on private lands?.......................................................................................................242

Issue 25 (Recreation): How will invasive plant management affect the management and use of recreation 

sites?..................................................................................................................................................................242

Issue 26 (Recreation): What are the effects of herbicides on dogs, horses, and other pets that accompany 

recreationists? ...................................................................................................................................................243

Issue 27 (Wilderness / Wilderness Study Areas): How will invasive plant management affect Wilderness or 

Wilderness Study Areas on the District? ...........................................................................................................244

Issue 28 (Visual): Would the use of invasive plant treatments affect the visual quality of the landscape? .....244

Figures

Figure A-1. Gross and Net Treatment Acres................................................................................................................73

Figure B-1. Prioritizing Areas for Treatment................................................................................................................83

Figure B-2. Weed Mats, held with Sand Bags (treating Eurasian watermilfoil in Michigan) .......................................86

Figure B-3. Ground-Based Herbicide Applications with Backpack Sprayer .................................................................91

Figure D-1. Bureau Sensitive Species Treatment Conditions.....................................................................................145

Figure F-1. Basis for Risk Assessments.......................................................................................................................208

Tables

Table A-1. Summary of Invasive Plants Documented in NISIMS by Infestation Size ...................................................74

Table A-2. Invasive Plants on the Northwest Oregon District .....................................................................................75

Table A-3. Invasive Plants Mapped in NISIMS by Infestation Size...............................................................................78

Table B-1. Widespread Biological Control Agents on the Northwest Oregon District ................................................88

Table B-2. Herbicide Information ................................................................................................................................92

Table B-3. Herbicide Characteristics............................................................................................................................95

Table B-4. Guide for Herbicide Rotation......................................................................................................................97

Table C-1. Annual Grasses: Locations and Treatment Key ........................................................................................100

Table C-2. Annual Peas: Locations and Treatment Key .............................................................................................101

Table C-3. Aquatic Species: Locations and Treatment Key........................................................................................102

Table C-4. Biennial Thistles: Locations and Treatment Key .......................................................................................104

Table C-5. Borage: Locations and Treatment Key......................................................................................................106

Table C-6. Buckwheat Family: Locations and Treatment Key....................................................................................107

Table C-7. Buttercups: Locations and Treatment Key ...............................................................................................108

Table C-8. Canada Thistle: Locations and Treatment Key .........................................................................................109

Table C-9. Carnations: Locations and Treatment Key................................................................................................110

Table C-10. Carrot Family: Locations and Treatment Key .........................................................................................111

Table C-11. Geranium: Locations and Treatment Key ...............................................................................................112

Table C-12. Hawkweeds: Locations and Treatment Key............................................................................................114

Table C-13. Knapweeds: Locations and Treatment Key ............................................................................................115
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Table C-14. Lilies, Iris, Sedges, Rushes: Locations and Treatment Key......................................................................116

Table C-15. Loosestrifes: Locations and Treatment Key............................................................................................117

Table C-16. Miscellaneous Herbaceous - Annual: Locations and Treatment Key......................................................118

Table C-17. Miscellaneous Herbaceous - Perennial: Locations and Treatment Key..................................................120

Table C-18. Mustards: Locations and Treatment Key................................................................................................122

Table C-19. Perennial Grasses: Locations and Treatment Key ..................................................................................123

Table C-20. Perennial Mints: Locations and Treatment Key......................................................................................125

Table C-21. Perennial Peas: Locations and Treatment Key .......................................................................................126

Table C-22. Snapdragons: Locations and Treatment Key ..........................................................................................128

Table C-23. Spurges: Locations and Treatment Key ..................................................................................................129

Table C-24. St. Johnswort: Locations and Treatment Key .........................................................................................130

Table C-25. Sunflower Family: Locations and Treatment Key ...................................................................................131

Table C-26. Teasel: Locations and Treatment Key.....................................................................................................133

Table C-27. Woody Species: Locations and Treatment Key.......................................................................................134

Table C-28. Summary of Species Group Information and Treatment Adequacy.......................................................137

Table C-29. Summary of Treatment Options Available under One or More Alternatives, by Species Group ...........138

Table C-30. Annual Treatment Plan...........................................................................................................................140

Table D-1. Buffer Distances to Minimize Risk to Vegetation from Off-Site Drift of BLM-Evaluated Herbicides .......164

Table D-2. Buffer Distances to Minimize Risk to Vegetation from Off-Site Drift of Forest Service-Evaluated 

Herbicides..................................................................................................................................................................164

Table D-3. Buffer Distances to Minimize Risk to Fish and Aquatic Invertebrates from Off-Site Drift of BLM-Evaluated 

Herbicides..................................................................................................................................................................165

Table D-4. Buffer Distances (in feet) to Minimize Risk to Non-target Vegetation from Off-site Drift.......................165

Table D-5. Listed Species on the Northwest Oregon District ....................................................................................165

Table D-6. Endangered Species Act Consultation......................................................................................................166

Table D-7. No-application buffer widths in feet for herbicide application, by stream types and application methods

...................................................................................................................................................................................183

Table D-8. Disturbance Distances and Time Periods When Disturbance (and Possibly Disruption) May Occur for 

Terrestrial Species .....................................................................................................................................................184

Table D-9. Optimal Survey Times for Flowering Periods of Listed Plants in Oregon and Washington......................185

Table D-10. Disturbance, disruption (harass) and/or physical injury (harm) distance thresholds for Spotted Owls.

...................................................................................................................................................................................186

Table D-11. Disturbance, disruption (harass) and/or physical injury (harm) distance thresholds for Marbled 

Murrelet during the nesting season ..........................................................................................................................187

Table E-1. General Constraints from Herbicide Labels..............................................................................................189

Table E-2. Herbicide Formulations Approved for Use on BLM-Administered Lands.................................................192

Table E-3. Adjuvants Approved for Use on BLM Administered Lands.......................................................................197

Table F-1. Herbicide Label Categories .......................................................................................................................204

Table F-2. Human Health and Ecological Risk Assessment Sources ..........................................................................206

Table F-3. BLM-Evaluated Herbicide Risk Categories for Vegetation ........................................................................210

Table F-4. BLM-Evaluated Herbicide Risk Categories for Wildlife, Fish, and Aquatic Species...................................211

Table F-5. BLM-Evaluated Herbicide Risk Categories for Human Health...................................................................214

Table F-6. Forest Service-Evaluated Herbicide Risk Categories for Vegetation.........................................................215

Table F-7. Forest Service-Evaluated Herbicide Risk Categories for Wildlife, Fish, and Aquatic Species....................216

Table F-8. Forest Service-Evaluated Herbicide Risk Categories for Human Health ...................................................218

Table G-1. Human Health Herbicide Risk Summary, Public.......................................................................................227

Table G-2. Summary of Effects of Herbicides on Human Health...............................................................................228

Table G-3. Human Health Herbicide Risk Summary, Workers...................................................................................230
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

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71

Maps

Map A-1 East. Terrestrial Invasive Plants Documented in NISIMS

Map A-1 West. Terrestrial Invasive Plants Documented in NISIMS

Map A-2. Aquatic Invasive Plants Documented in NISIMS

Map A-3 East: Routes of Invasive Plant Spread: Recreation Sites and Waterways

Map A-3 West. Routes of Invasive Plant Spread: Recreation Sites and Waterways

Map A-4 East. Routes of Invasive Plant Spread: Ground Transportation Road Network

Map A-4 West. Routes of Invasive Plant Spread: Ground Transportation Road Network

Map A-5 East. Routes of Invasive Plant Spread: Material Sites and Mineral Resources

Map A-5 West. Routes of Invasive Plant Spread: Material Sites and Mineral Resources

Map A-6 East. Routes of Invasive Plant Spread: Transmission Lines and Water Developments

Map A-6 West. Routes of Invasive Plant Spread: Transmission Lines and Water Developments

Map A-7. Routes of Invasive Plant Spread: Landcover and Population Centers
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Appendix A –Invasive Plants on the District

72

Appendix A: Invasive Plants on the 

District

This appendix summarizes information about infestations of invasive plants on the District, including known or 

estimated invasive plant sites, to help clarify invasive plant treatments described in Appendices B and C and the 

analysis in Chapter 3 and Appendix G. An invasive plant thrives and spreads aggressively outside its natural range. 

An invasive species that colonizes a new area may gain an ecological edge since the insects, diseases, and foraging 

animals that naturally keep its growth in check in its native range are not present in its new habitat. The 

susceptibility of plant communities to colonization by invasive plants is influenced by many factors, including 

community structure, disturbance, proximity to infested areas, and the biological traits of the invading species.

Existing Invasive Plant Sites

This section describes infestations known to occur on the District, some of which the BLM has digitally mapped in 

GIS, and others the BLM estimated or documented on paper maps. Invasive plant inventories on the District focus 

on locations where invasive plants are most likely to occur and spread from, such as waterways, road corridors, 

and areas with recent or frequent disturbance. The BLM also conducts project clearance or risk assessment 

surveys1 in advance of planned projects, such as forest management projects, so the BLM can take measures to 

prevent the introduction and spread of invasive plants into and from project areas. The District maps and 

documents invasive plant infestations found through inventories, project risk assessment surveys, and incidental 

observations made during the course of conducting other land management work. Most of the known invasive 

plant sites documented on the District have been found by BLM staff and contractors completing inventories and 

project risk assessment surveys. The BLM is required to monitor new project areas with moderate likelihood of 

noxious weed introduction2 for the first three years after completion and areas with high likelihood for five years 

(USDI 1992b).

The District uploads inventory data to the BLM’s National Invasive Species Information Management System 

(NISIMS), the GIS that links to BLM planning and reporting systems. NISIMS records include the infestation’s spatial 

location, size, and shape; the invasive plant’s abundance and distribution pattern; treatment records; and other 

associated characteristics. Sites where the species appear to have been controlled are retained in NISIMS to guide 

future site monitoring. The BLM has historically had data sharing agreements with the Oregon Department of 

Agriculture to make District noxious weed distribution information available to the public on their WeedMapper

website. The BLM also shares data with the IMapInvasives website. In addition, the BLM is in the process of making 

NISIMS data about invasive plant sites and treatment history accessible to the public.

The most prevalent species mapped on the District in NISIMS are Scotch broom, slender false brome, St. 

Johnswort, tansy ragwort, thistles, and blackberry (Himalayan and cutleaf)3

. NISIMS includes 81 different invasive 

 1 Surveys are conducted to determine if an invasive plant is present or absent in a project area. If presence is confirmed, 

inventories are completed to catalog the abundance and distribution of the invasive plants present. 2 Generally, any type of project resulting in ground disturbance, such as slash / pile / burn units, timber harvest areas, road / 

bridge construction, and trail construction. Current handbook direction requires this assessment only for noxious weeds 

(Integrated Weed Management Manual 9015; USDI 1992b). Handbook direction is in the process of being updated to include all 

invasive plant species in order to comply with Executive Order 13112 (February 1999, amended December 2016). 3 St. Johnswort, tansy ragwort, and thistle infestations tend to be less dense than other widespread species; these species may

occur on more gross acres but have fewer net acres than other pervasive invasive plants.
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix A –Invasive Plants on the District

73

plant species occupying 17,430 acres on 49,491 sites4 on the District. In addition, there are species and infestations 

that are known to occur on the District, but are not mapped in NISIMS. These species are generally widespread and 

dispersed throughout the District. Field office invasive plant management staff estimated these unmapped areas 

based on their professional judgement and field experience. While the locations are not mapped, it is possible to 

characterize the areas and habitat where they may occur. Some of these species are widespread, and while the 

precise acreage occupied by these species on the District is unknown, the unmapped acres column in the tables in 

Appendix C indicates how many additional acres invasive plant management staff estimate to be in need of 

treatment. Map A-1, Invasive Plants Documented in NISIMS shows the locations of mapped invasive plants. Map A2, Submerged and Floating Aquatic Invasive Plants, shows the locations of mapped aquatic invasive plants.

As shown in Figure A-1, the gross infested area is the area of land defined by drawing a line around the general 

perimeter of the infestation, and does not reflect the percent cover of the plants. This area may contain large 

areas of land that are not occupied by an invasive plant species. Net acres are the actual infestation within the 

area. In some areas, a large area may have a sparse infestation and net acres would be calculated by multiplying

the gross acres by the percent cover of the infestation. The net acres of many infestations on the District is not 

known; hence, acres described in this analysis are gross acres.

Figure A-1. Gross and Net Treatment Acres

 4 Many of these sites overlap with sites of other invasive plants species. For example, a blackberry infestation may exist on the 

same acreage as a thistle infestation. 
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix A –Invasive Plants on the District

74

Table A-1. Summary of Invasive Plants Documented in NISIMS by Infestation Size

Tables A-1 and A-3 indicate the size of invasive plant 

infestations mapped in NISIMS within the Northwest 

Oregon District boundary. Eighty-five percent of 

mapped sites are smaller than one gross acre each (see 

Table A-1 and Table A-3, Invasive Plants Mapped in 

NISIMS by Infestation Size); however, a relatively small 

number of large sites account for a majority of infested 

acres (about 39 percent of the mapped acres are on 

sites that are larger than 5 gross acres).

Spread from Existing Invasive Plant Sites

As described in the Oregon FEIS, the current spread rate for noxious weeds is estimated to be about 12 percent 

annually (USDI 2010a:135-137, 594-597) and new sites are found on the District with each invasive plant inventory. 

As described in the Proposed Resource Management Plan/Final Environmental Impact Statement for the Resource 

Management Plans for Western Oregon, timber harvest, road construction, and public motorized vehicle use can 

all contribute to invasive plant spread as well as actions such as management of special forest products, rights-ofway agreements, road maintenance, and fuels reduction treatments (USDI 2016e:419-438). Invasive plants can 

spread quickly and over great distances by wind, water, animals, and humans through vehicle and foot traffic. 

Infestations begin mostly on disturbed sites such as roads and trails, logged areas, burned areas, cultivated fields 

and pastures, wildlife concentration areas, mining areas, and recreation sites. Wildlife (including birds) can 

introduce invasive plant seeds from their coats and feces (USDI 2010a:132). Proximity to urban areas and the 

checkerboard ownership pattern increases opportunities for invasive plant movement onto the District (See Map 

A-7, Routes of Invasive Plant Spread: Landcover and Population Centers).

Linear disturbances such as roads and utility corridors are primary pathways for spread on the District. Many 

invasive plant species for which there are no currently available effective control methods are being spread along 

roads by vehicles annually. (See Map A-4, Routes of Invasive Plant Spread: Ground Transportation Network and 

Map A-6, Transmission Lines and Water Developments.)

Water developments such as heliponds, reservoirs, and water tanks and troughs may also spread invasive plants 

throughout the District. For example, aquatic invasive plants in heliponds (areas where surface water is available 

for firefighting operations) have the potential to be spread into newly disturbed burned areas. (Map A-6, 

Transmission Lines and Water Developments.)

Streams are also major pathways for the movement of invasive plants. The Willamette, Sandy, Nestucca, Siletz, 

and their tributaries transport invasive plant propagules downstream. These areas attract birds, wildlife, and 

humans who spread invasive plants along these corridors. (See Map A-3, Routes of Invasive Plant Spread: 

Recreation Sites and Waterways.)

Recreation sites, both developed and dispersed, are the hub of several means of invasive plant spread. Recreation 

sites bring together people and their recreation equipment, vehicles, pack stock, and pets where roads, trails, and 

waterways converge. Invasive plants are easily transported from one site to other areas on the District and 

beyond. (See Map A-3, Routes of Invasive Plant Spread: Recreation Sites and Waterways.)

Timber harvest, restoration, prescribed fire, and silviculture activities disturb vegetation and soil in ways that can 

stimulate existing invasive plant seed banks, reduce barriers to invasive seed dispersal, and improve site conditions 

for invasive plant establishment and growth. Particularly where project disturbances are more severe, such as skid 

roads and burn pile scars, invasive plant infestations can persist and become sources for further invasive plant

spread. Equipment and work crews can also spread invasive plants to and from project areas.

Infestation 

Size (in Acres)

Number of Sites

(percent of total sites)

Total Acres

(percent of total acres)

< 0.1 17,173 22% 1,142 2%

0.1 to < 0.5 37,065 48% 10,177 16%

0.5 to < 1 10,772 14% 7,742 12%

1 to < 5 10,066 13% 19,019 31%

5 to < 20 1,445 2% 13,036 21%

20 to <100 285 <1% 9,400 15%

>100 7 <1% 1,426 2%
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendix A –Invasive Plants on the District

75

Mineral material sites such as quarries and mining operation sites are continuously disturbed and may have 

numerous users. Vegetation and top soil are removed during mining activities, and revegetation efforts may need 

several successional phases in order to reclaim the site. During these phases, the site may be vulnerable to 

establishment by invasive plants. (See Map A-5, Routes of Invasive Plant Spread: Material Sites and Mineral 

Resources.)

Potential New Invaders

Species of invasive plants not previously documented on the District may be found at any time. Initial infestations 

are small, but may become large before being discovered. BLM staff, partners, and contractors check common 

routes of spread (e.g., roads and waterways) regularly. Species of concern not yet documented on the District but 

documented on adjacent lands include garlic mustard, false indigo bush, Eurasian watermilfoil, water primrose, 

floating water primrose, and tree-of-heaven. For example, garlic mustard is present around Colton, Estacada, and 

Welches on public and private lands close to BLM, but has yet to be detected on BLM-administered lands. The 

District works with numerous entities to coordinate early detection activities across jurisdictional boundaries and 

educate the public about new invasive plants that are invading the area. The District assigns all new invaders a high 

priority for treatment in order to prevent them from becoming established on the District (see further information 

in the Prioritizing Areas for Treatment section in Appendix B).

Table A-2. Invasive Plants on the Northwest Oregon District

Common Name Scientific Name Species Group (Treatment Key Table) Known on District? Noxious 

Weed?

Red top, creeping 

bentgrass Agrostis stolonifera Perennial Grasses (Table C-19) Existing

Tree of heaven Ailanthus altissima Woody Species (Table C-27) Potential new invader 

Garlic mustard Alliaria petiolata Mustards (Table C-18) Potential new invader 

Meadow foxtail Alopecurus pratensis Perennial Grasses (Table C-19) Existing

European beachgrass Ammophila arenaria Perennial Grasses (Table C-19) Existing

False indigo bush Amorpha fruticosa Perennial Peas (Table C-21) Potential new invader 

Common bugloss Anchusa officinalis Borage (Table C-5) Potential new invader 

Sweet vernal grass Anthoxanthum odoratum Perennial Grasses (Table C-19) Existing

Common burdock Arctium minus Biennial Thistles (Table C-4) Existing

Tall oatgrass Arrhenatherum elatius Perennial Grasses (Table C-19) Existing

Italian arum Arum italicum Lilies, Iris, Sedges, Rushes (Table C-14) Potential new invader

Wild oat Avena fatua Annual Grasses (Table C-1) Existing 

Slender false brome Brachypodium sylvaticum Perennial Grasses (Table C-19) Existing 

Soft brome Bromus hordeaceus Annual Grasses (Table C-1) Existing 

Butterfly bush Buddleja davidii Woody Species (Table C-27) Existing 

Flowering rush Butomus umbellatus Aquatic Species (Table C-3) Potential new invader 

Italian thistle Carduus pycnocephalus Biennial Thistles (Table C-4) Potential new invader 

Distaff thistle Carthamus lanatus Biennial Thistles (Table C-4) Potential new invader 

Meadow knapweed Centaurea ×moncktonii Knapweeds (Table C-13) Existing 

Diffuse knapweed Centaurea diffusa Knapweeds (Table C-13) Existing 

Malta thistle Centaurea melitensis Knapweeds (Table C-13) Potential new invader

Yellow starthistle Centaurea solstitialis Knapweeds (Table C-13) Existing 

Spotted knapweed Centaurea stoebe L. ssp. 

micranthos Knapweeds (Table C-13) Existing 

Canada thistle Cirsium arvense Canada Thistle (Table C-8) Existing 

Bull thistle Cirsium vulgare Biennial Thistles (Table C-4) Existing 

Old man's beard Clematis vitalba Woody Species (Table C-27) Potential new invader 

Poison hemlock Conium maculatum Carrot Family (Table C-10) Existing 
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendix A –Invasive Plants on the District

76

Common Name Scientific Name Species Group (Treatment Key Table) Known on District? Noxious 

Weed?

Field bindweed Convolvulus arvensis Miscellaneous Herbaceous - Perennial 

(Table C-17) Existing 

Jubata grass Cortaderia jubata Perennial Grasses (Table C-19) Potential new invader 

Cotoneaster spp. Cotoneaster Woody Species (Table C-27) Existing

Hawthorn Crataegus Woody Species (Table C-27) Existing

Oneseed hawthorn Crataegus monogyna Woody Species (Table C-27) Existing

Gypsyflower/ 

houndstounge Cynoglossum officinale Borage (Table C-5) Existing 

Scotch broom Cytisus scoparius Woody Species (Table C-27) Existing 

Striated broom Cytisus striatus Woody Species (Table C-27) Existing 

Orchardgrass Dactylis glomerata Perennial Grasses (Table C-19) Existing

Spurge laurel Daphne laureola Woody Species (Table C-27) Existing 

Purple foxglove Digitalis purpurea Snapdragons (Table C-22) Existing

Fuller's teasel Dipsacus fullonum Teasel (Table C-26) Existing

Patterson’s curse Echium plantagineum Borage (Table C-5) Potential new invader 

Weeping lovegrass Eragrostis curvula Perennial Grasses (Table C-19) Potential new invader

Leafy spurge Euphorbia esula Spurges (Table C-23) Existing 

Oblong spurge Euphorbia oblongata Spurges (Table C-23) Potential new invader 

Common fennel Foeniculum vulgare Carrot Family (Table C-10) Potential new invader

French broom Genista monspessulana Woody Species (Table C-27) Existing 

Shining geranium Geranium lucidum Geranium (Table C-11) Existing 

Herb Robert Geranium robertianum Geranium (Table C-11) Existing 

Waxy mannagrass Glyceria declinata Perennial Grasses (Table C-19) Potential new invader

English ivy Hedera helix Woody Species (Table C-27) Existing 

Giant hogweed Heracleum mantegazzianum Carrot Family (Table C-10) Existing 

Orange hawkweed Hieracium aurantiacum Hawkweeds (Table C-12) Existing

Yellow hawkweed Hieracium floribundum Hawkweeds (Table C-12) Potential new invader

Common velvet grass Holcus lanatus Perennial Grasses (Table C-19) Existing

Creeping velvet grass Holcus mollis Perennial Grasses (Table C-19) Existing

Hydrilla Hydrilla verticillata Aquatic Species (Table C-3) Existing 

St. Johnswort Hypericum perforatum St (Table C-24) Existing 

English holly Ilex aquifolium Woody Species (Table C-27) Existing

Policeman's helmet Impatiens glandulifera Miscellaneous Herbaceous - Annual 

(Table C-16) Existing 

Yellow flag iris / 

paleyellow iris Iris pseudacorus Lilies, Iris, Sedges, Rushes (Table C-14) Existing 

Dyers woad Isatis tinctoria Mustards (Table C-18) Potential new invader 

Yellow archangel Lamiastrum galeobdolon Perennial Mints (Table C-20) Existing

Perennial pea Lathyrus latifolius Perennial Peas (Table C-21) Existing 

Flat pea Lathyrus sylvestris Perennial Peas (Table C-21) Existing 

Purpleanther field 

pepperweed Lepidium heterophyllum Mustards (Table C-18) Existing

Oxeye daisy Leucanthemum vulgare Sunflower Family (Table C-25) Existing

Butter and eggs Linaria vulgaris Snapdragons (Table C-22) Existing 

Birdsfoot trefoil Lotus corniculatus Perennial Peas (Table C-21) Existing

Water primrose Ludwigia hexapetala Aquatic Species (Table C-3) Potential new invader 

Floating water 

primrose Ludwigia peploides Aquatic Species (Table C-3) Potential new invader 

Money plant Lunaria annua Mustards (Table C-18) Potential new invader

Creeping jenny Lysimachia nummularia Loosestrifes (Table C-15) Existing

Garden loosestrife Lysimachia vulgaris Loosestrifes (Table C-15) Potential new invader 

Purple loosestrife Lythrum salicaria Loosestrifes (Table C-15) Potential new invader 

Sweetclover Melilotus offincinalis Annual Peas (Table C-2) Existing
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendix A –Invasive Plants on the District

77

Common Name Scientific Name Species Group (Treatment Key Table) Known on District? Noxious 

Weed?

Pennyroyal Mentha pulegium Perennial Mints (Table C-20) Existing

Parrot feather Myriophyllum aquaticum Aquatic Species (Table C-3) Existing 

Eurasian watermilfoil Myriophyllum spicatum Aquatic Species (Table C-3) Potential new invader 

Daffodil Narcissus Lilies, Iris, Sedges, Rushes (Table C-14) Existing

Fragrant water lily Nymphaea odorata Aquatic Species (Table C-3) Potential new invader

Yellow floating heart Nymphoides peltata Aquatic Species (Table C-3) Potential new invader 

Scotch cottonthistle Onopordum acanthium Biennial Thistles (Table C-4) Existing 

Bulbous canarygrass Phalaris aquatica Perennial Grasses (Table C-19) Existing

Reed canarygrass Phalaris arundinacea Perennial Grasses (Table C-19) Existing 

Timothy Phleum pratense Perennial Grasses (Table C-19) Existing

Bristly oxtongue PIcris echioides Sunflower Family (Table C-25) Potential new invader

Japanese knotweed Polygonum cuspidatum Buckwheat Family (Table C-6) Existing 

Cultivated knotweed Polygonum polystachyum Buckwheat Family (Table C-6) Existing 

Giant knotweed Polygonum sachanlinense Buckwheat Family (Table C-6) Existing 

Bohemian knotweed Polygonum X bohemicum Buckwheat Family (Table C-6) Existing

Sulfur cinquefoil Potentilla recta Miscellaneous Herbaceous - Perennial 

(Table C-17) Potential new invader 

Sweet cherry Prunus avium Woody Species (Table C-27) Existing

Cherry laurel Prunus laurocerasus Woody Species (Table C-27) Potential new invader

Kudzu Pueraria lobata Perennial Peas (Table C-21) Potential new invader 

Common pear Pyrus communis Woody Species (Table C-27) Existing

Lesser celandine Ranunculus ficaria Buttercups (Table C-7) Potential new invader 

Creeping buttercup Ranunculus repens Buttercups (Table C-7) Existing

Cultivated radish Raphanus sativus Mustards (Table C-18) Existing

Creeping yellowcress Rorippa sylvestris Mustards (Table C-18) Existing 

Non-native invasive 

roses Rosa Woody Species (Table C-27) Existing

Multiflora rose Rosa multiflora Woody Species (Table C-27) Existing

Cutleaf blackberry Rubus laciniatus Woody Species (Table C-27) Existing

Himalayan blackberry Rubus armeniacus Woody Species (Table C-27) Existing 

European blackberry Rubus vestitus Woody Species (Table C-27) Existing

Curly dock Rumex crispus Buckwheat Family (Table C-6) Existing

Tall fescue Schedonorus arundinaceus Perennial Grasses (Table C-19) Existing

Stinking willie, tansy 

ragwort Senecio jacobaea Sunflower Family (Table C-25) Existing 

Bladder campion Silene vulgaris Carnations (Table C-9) Existing

Milk thistle Silybum marianum Biennial Thistles (Table C-4) Existing 

Bittersweet / 

Climbing nightshade Solanum dulcamara Miscellaneous Herbaceous - Perennial (Table C-17) Existing

Spanish broom Spartium junceum Woody Species (Table C-27) Existing 

Medusahead Taeniatherum caput-medusae Annual Grasses (Table C-1) Existing 

Puncturevine Tribulus terrestris Miscellaneous Herbaceous - Annual 

(Table C-16) Existing 

Coltsfoot Tussilago farfara Sunflower Family (Table C-25) Existing 

Common gorse Ulex europaeus Woody Species (Table C-27) Existing 

North Africa grass Ventenata dubia Annual Grasses (Table C-1) Existing

Brazilian verbena Verbena bonariensis Miscellaneous Herbaceous - Perennial 

(Table C-17) Existing

Bigleaf periwinkle Vinca major Miscellaneous Herbaceous - Perennial 

(Table C-17) Existing

Common periwinkle Vinca minor Miscellaneous Herbaceous - Perennial 

(Table C-17) Existing
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix A –Invasive Plants on the District

78

Table A-3. Invasive Plants Mapped in NISIMS by Infestation Size

Common Name Scientific Name

Sites >100 acres Sites 20 to 100 

acres Sites 5 to 20 acres Sites 1 to 5 acres Sites 0.5 to 1 acre

Sites 0.1 and 

<0.5 acres Sites <0.1 acre

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Bigleaf periwinkle Vinca major 1 9.15 3 0.30 1 0.07

Birdsfoot trefoil Lotus corniculatus 3 0.60 2 0.03

Bittersweet / Climbing nightshade Solanum dulcamara 6 3.58 14 4.67 1 0.07

Bohemian knotweed Polygonum X bohemicum 2 0.13

Bulbous canarygrass Phalaris aquatica 2 1.24 1 0.13 11 0.24

Bull thistle Cirsium vulgare 36 1,085.51 87 831.81 881 1,574.23 863 627.31 2,289 717.06 1,606 108.54

Butter and eggs Linaria vulgaris 2 0.27 4 0.31

Butterfly bush Buddleja davidii 2 0.20 2 0.12

Canada thistle Cirsium arvense 31 950.98 53 493.12 455 741.03 788 569.64 2,487 821.04 1,269 86.83

Common burdock Arctium minus 2 25.43 4 4.67 5 3.48 16 5.44

Common gorse Ulex europaeus 2 0.04

Common pear Pyrus communis 2 43.28 2 17.78 2 2.83

Common periwinkle Vinca minor 1 2.50 3 1.62 12 1.97 12 1.19

Common velvet grass Holcus lanatus 6 234.48 14 120.90 8 14.92 2 1.24 13 3.02 22 0.59

Cotoneaster spp. Cotoneaster 1 0.02

Creeping buttercup Ranunculus repens 9 1.23 3 0.05

Creeping jenny Lysimachia nummularia 1 0.39 2 0.07

Creeping velvet grass Holcus mollis 1 0.58 9 1.20 34 3.29

Creeping yellowcress Rorippa sylvestris 2 4.03 2 1.77 85 9.52 4 0.15

Cultivated knotweed Polygonum polystachyum 1 1.07 1 0.50 2 0.20

Cultivated radish Raphanus sativus 1 0.10

Curly dock Rumex crispus 1 1.60 3 1.94 7 1.37 10 0.51

Cutleaf blackberry Rubus laciniatus 4 138.94 21 199.59 575 922.26 891 638.82 3,248 928.70 1,689 106.22

Daffodil Narcissus 1 0.01

Diffuse knapweed Centaurea diffusa 1 1.04 2 1.50 1 0.14 1 0.10

English holly Ilex aquifolium 1 5.58 4 12.42 47 9.84 33 2.59

English ivy Hedera helix 3 22.71 13 22.49 9 5.66 52 13.45 51 2.79

European beachgrass Ammophila arenaria 2 35.66 1 2.01 1 0.59 1 0.47 5 0.32

European blackberry Rubus vestitus 1 38.34 2 14.61 14 36.16 22 15.75 37 10.66 144 10.30

Field bindweed Convolvulus arvensis 1 0.99 32 11.59 3 0.11

Flat pea Lathyrus sylvestris 1 2.86 5 0.97

French broom Genista monspessulana 2 11.77 4 1.03 1 0.04

Fuller's teasel Dipsacus fullonum 1 5.41 2 3.19 8 5.41 21 3.91 126 4.11

Giant hogweed Heracleum mantegazzianum 1 0.18

Giant knotweed Polygonum sachanlinense 3 6.46 10 2.76 3 0.16

Gypsyflower / Houndstongue Cynoglossum officinale 1 0.10

Hawthorn Crataegus 2 43.28 6 47.27 7 17.49 29 0.43
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix A –Invasive Plants on the District

79

Common Name Scientific Name

Sites >100 acres Sites 20 to 100 

acres Sites 5 to 20 acres Sites 1 to 5 acres Sites 0.5 to 1 acre

Sites 0.1 and 

<0.5 acres Sites <0.1 acre

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Herb Robert Geranium robertianum 1 107.39 4 172.76 16 143.22 129 290.32 104 70.30 865 137.05 483 28.58

Himalayan blackberry Rubus armeniacus 2 339.71 41 1,478.13 250 2,301.51 1,373 2,707.19 1,449 1,031.84 6,914 1,643.46 2,680 186.56

Japanese knotweed Polygonum cuspidatum 1 23.57 1 7.55 2 3.02 10 7.24 62 14.49 45 2.62

Leafy spurge Euphorbia esula 1 1.38

Meadow foxtail Alopecurus pratensis 1 22.37 2 20.68 3 12.37 3 0.43 11 0.24

Meadow knapweed Centaurea ×moncktonii 4 90.60 73 576.21 328 708.03 289 212.80 571 150.53 292 19.19

Medusahead Taeniatherum caput-medusae 1 4.39 1 0.10

Multiflora rose Rosa multiflora 3 6.10 3 1.73 9 2.09 36 0.77

Non-native invasive roses Rosa 1 10.28 1 1.84 1 0.52 3 0.39 9 0.25

Oneseed hawthorn Crataegus monogyna 1 12.49 13 0.14

Orange hawkweed Hieracium aurantiacum 3 0.21

Orchardgrass Dactylis glomerata 1 0.47 15 0.26

Oxeye daisy Leucanthemum vulgare 7 14.98 1 0.57 12 2.29 69 2.13

Parrot feather Myriophyllum aquaticum 4 0.24

Perennial pea Lathyrus latifolius 7 357.35 3 46.23 9 17.82 23 16.08 205 46.29 26 1.76

Poison hemlock Conium maculatum 4 1.15 21 0.64

Policeman's helmet Impatiens glandulifera 17 3.92

Purple foxglove Digitalis purpurea 20 135.44 611 1,038.10 720 521.90 1,769 628.88 7 0.48

Purpleanther field pepperweed Lepidium heterophyllum 4 0.03

Red top / Creeping bentgrass Agrostis stolonifera 2 76.69 2 16.66 7 23.51 4 3.19 5 1.48 17 0.59

Reed canarygrass Phalaris arundinacea 1 21.24 3 20.45 22 43.64 43 30.79 238 79.09 351 16.08

Scotch broom Cytisus scoparius 3 790.28 53 1,749.69 543 4,894.95 2,617 5,306.50 2,319 1,668.87 7,082 1,858.70 3,347 243.62

Scotch cottonthistle Onopordum acanthium 2 0.53 1 0.10

Shining geranium Geranium lucidum 15 23.35 27 19.11 478 72.77 269 8.07

Slender false brome Brachypodium sylvaticum 1 188.36 8 359.31 90 773.97 549 1,130.55 483 337.00 3,227 645.20 1,867 131.01

Soft brome Bromus hordeaceus 5 1.49 17 0.50

Spanish broom Spartium junceum 1 0.68 1 0.38

Spotted knapweed Centaurea stoebe L. ssp. 

micranthos 4 39.41 8 14.25 19 12.30 124 37.40 56 4.05

St. Johnswort Hypericum perforatum 38 1,153.30 121 1,088.57 1,246 2,271.98 1,315 951.15 3,555 1,177.74 45 2.82

Stinking willie / Tansy ragwort Senecio jacobaea 37 1,143.34 98 920.58 1,045 1,820.70 1,217 877.05 2,998 947.58 2,343 158.28

Striated broom Cytisus striatus 2 0.21 1 0.04

Sweet cherry Prunus avium 1 0.24

Sweet vernal grass Anthoxanthum odoratum 5 186.71 15 138.35 14 33.09 5 3.14 11 2.57 11 0.36

Sweetclover Melilotus offincinalis 75 108.47 115 83.37 444 159.64 5 0.44

Tall fescue Schedonorus arundinaceus 4 37.58 21 55.97 8 6.05 11 2.98 24 0.86

Tall oatgrass Arrhenatherum elatius 1 10.81 3 8.38 6 4.21 9 1.90 13 0.55

Timothy Phleum pratense 2 0.10
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Appendix A –Invasive Plants on the District

80

Common Name Scientific Name

Sites >100 acres Sites 20 to 100 

acres Sites 5 to 20 acres Sites 1 to 5 acres Sites 0.5 to 1 acre

Sites 0.1 and 

<0.5 acres Sites <0.1 acre

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Total 

Acres

Number 

of Sites

Wild oat Avena fatua 6 0.08

Yellow archangel Lamiastrum galeobdolon 1 29.98 7 1.61 3 0.25

Yellow flag iris / paleyellow iris Iris pseudacorus 2 0.29

Yellow starthistle Centaurea solstitialis 1 0.25
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix B – Integrated Invasive Plant Management 

81

Appendix B: Integrated Invasive 

Plant Management

This appendix explains how various methods are used together programmatically to control invasive plants. 

Actions taken for prevention, education, and coordination are described as context and do not vary between 

alternatives. This appendix also describes direct control methods, which may vary between alternatives. Direct 

control methods include manual and mechanical treatment methods, competitive planting and seeding, 

solarization, prescribed fire, biological treatment methods (insects and targeted grazing), and herbicide 

application.

As noted in Chapter 1, the action alternatives would update the direct control methods that are available to the 

existing invasive plant management program, making all treatment options available to the entire district and 

increasing the number of herbicides available for use. In addition, Alternatives 2 and 3 would allow herbicide 

treatments on invasive plants that are not listed as noxious weeds District-wide. (Currently, the District uses 

herbicides in the West Eugene Wetlands to control invasive plants, including noxious weeds. The Cascades, Marys 

Peak, and Tillamook Field Offices can treat only plants that are listed by the State as noxious. Outside of the West 

Eugene Wetlands and Tyrrell Seed Orchard5

, the Siuslaw and Upper Willamette Field Offices do not use 

herbicides.) Other elements of the program would remain the same across all alternatives. These unchanging 

elements of the program, including prevention, education, awareness, coordination, cooperation, planning, and 

monitoring are described below. This is followed by information on direct control methods, which varies by 

alternative.

Prevention, Education, and Awareness

Prevention, education, and awareness are the highest priority for the management of invasive plants. The District 

has incorporated weed prevention into regular field work and project management practices. Examples of 

prevention practices include cleaning vehicles and equipment before moving onto or from BLM-administered lands 

and helping with community invasive plant education events. Specific responsibilities are assigned for keeping 

administrative sites free of invasive plants, reestablishing desirable vegetation on disturbed sites, inspecting gravel 

and other materials sites, and including invasive plant prevention measures in all planning documents, contracts, 

and leases. Other prevention activities include the continuing education of employees, contractors, and the public.

Additionally, BLM policy requires that planning for ground-disturbing projects, or projects that have the potential 

to alter plant communities, include an assessment of the risk of introducing or spreading noxious weeds (USDI 

1992b). The District practice, however, is to include all invasive plant species in these project risk assessments. If 

there is a moderate or high risk of spread, actions to reduce the risk must be implemented and monitoring of the 

site (see Monitoring section below) must be conducted to prevent establishment of new infestations (USDI 1992b). 

The BLM requires weed-free forage for pack stock, weed-free seed for revegetation projects, and weed-free straw 

for erosion control, and specifies in contracts that materials brought on to the District are to be weed-free. The 

District uses competitive seeding and planting as both a preventative and a control measure. Further information 

can be found in the Direct Control Methods section later in this appendix.

The District actively contributes and participates with other organizations to provide workshops and trainings for a 

wide variety of publics and organizations (see next section). 

 5 This EA does not address invasive plant management at the Horning Seed Orchard (Cascades Field Office) and Tyrell Seed 

Orchard (Siuslaw Field Office).
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix B – Integrated Invasive Plant Management 

82

Coordination and Cooperation

Due to the size of the population centers and the amount of human development within the District, there are 

dozens of organizations working cooperatively to combat the spread of invasive plants. These organizations 

include other Federal entities like the U.S. Forest Service and the U.S. Army Corps of Engineers; state entities such 

as the Oregon Department of Agriculture (ODA) and the Oregon Department of Transportation (ODOT); as well as 

local cities, counties, Tribes, watershed councils, non-governmental organizations, and private landowners. District

staff work in cooperation with the Western Invasives Network, its associated Cooperative Weed Management 

Areas, and Soil and Water Conservation Districts. The District is also involved with the Northwest Oregon 

Restoration Partnership and the Clackamas River Invasive Species Partnership.

Coordination includes the implementation of prevention and education activities (see previous section), sharing of 

inventory and monitoring information, and developing and implementing annual treatment programs. The District 

works closely with Oregon Parks and Recreation Department, ODA, ODOT, and the Oregon Department of 

Forestry, as well as watershed councils and other non-governmental organizations through interagency and 

cooperative agreements in which grant monies and BLM contributions help fund youth crews, volunteer “Let’s Pull 

Together” events, and other invasive plant treatments on BLM and adjacent lands.

Planning

Integrated invasive plant management includes a process to determine when and where to take management 

action. The Integrated Vegetation Management Manual (USDI 2008a:59) describes an adaptive management 

approach based on clearly identified outcomes (see Prioritizing Areas for Treatments, below), monitoring to 

determine if management actions are meeting outcomes (see Monitoring, below), and if not, facilitating 

management changes that will best ensure that outcomes are met or re-evaluated (see Appendix C, Tables C-1 to 

C-27, Treatment Key). 

In general, the District’s strategy is to manage invasive plants while minimizing adverse effects to ecological 

function and economic values. This strategy requires District staff to set action thresholds and to evaluate sites to 

determine when the BLM has reached or exceeded those thresholds. Action thresholds are the levels of ecological 

or economic damage that invasive plant infestations cause before needing treatments, and these thresholds differ 

across sites, projects, and species. For example, for most invasive plant species, the action threshold would be 

different along a disturbed roadside than it would be next to a population of a rare plant species known to be 

intolerant of competition. For some invasive plant species (e.g., giant hogweed) the threshold may be a single 

plant, regardless of the site, while for other species (e.g., St. Johnswort) the threshold would rarely be reached 

except at extremely sensitive sites.

Prioritizing Areas for Treatment

The District recommends management action for invasive plant infestations that exceed action thresholds. The 

District prioritizes treatment sites because the number of invasive plant infestations requiring management action 

exceeds the District’s annual treatment capacity. Priorities are determined based on abundance of the target 

species (e.g., is it previously unknown on the District, or is it widespread?), location where the infestation is found, 

type and value of resources near the infestation, potential rate and severity of spread, and whether the treatment 

would be effective.

Early Detection Rapid Response (EDRR) is used whenever possible to prevent establishment and increase chances 

of eradication. Infestations targeted for EDRR include:
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• Species included on District, cooperative weed management area, and state EDRR lists.

• Observations of non-native species spreading quickly (even if they are not already included on an EDRR list).

• Small outlier infestations of established invasive plant species.

The following factors help the District set treatment priorities:

• Whether the species or infestation is EDRR, new invader, or an established species.

• The proximity of the infestation to ground disturbing project planned and sensitive resources (rare species, 

special management areas)

• The proximity of the infestation to administrative sites and areas likely to serve as sources of spread (e.g., 

recreation sites, gravel stockpiles, roads, major rights-of-way).

• Whether the infestation is part of a partnered project (allowing for an opportunity to combine resources).

• Whether the species or infestation is currently or potentially could cause high ecological or economic impacts.

It is a higher priority to retreat an infestation than to start treatment on a new infestation.

Treatment objectives for priority infestations are generally as follows:

• EDRR – treat for eradication.

• New Invaders – treat for eradication if possible; otherwise, containment to decrease infestation size and 

prevent spread

• Established species – treat to contain infestations, decrease infestation size and density, and prevent the 

infestation from spreading.

Figure B-1 shows a generalized process for prioritizing invasive plant treatments across the District.

Figure B-1. Prioritizing Areas for Treatment

1. These areas include Table Rock Wilderness Area, Little Sink Instant Study Area, Special Recreation Management Ares and Extensive 

Recreation Management Areas, ACECs, Special Status species habitat, and lands managed for their wilderness characteristics.
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Monitoring

Monitoring is required for many resources managed by the BLM. Some of this monitoring, while not directly done 

because of the invasive plant program, can reveal information about the program. For example, habitat quality 

monitoring at the West Eugene Wetlands for federally listed species has shown that invasive plant species are in all 

monitored sites (Gray and Bahm 2015). Directly related to the invasive plant program, BLM staff monitor many 

timber sales for invasive plant infestations for three to five years following harvest. Implementation and 

effectiveness monitoring are also required (Integrated Vegetation Management Handbook, USDI 2008a:71). The 

methods in these handbooks and manuals are followed and adjusted as necessary for different sites and 

objectives. Data from monitoring identifying the location of invasive plants are recorded in NISIMS.

Implementation Monitoring

BLM policy and the EPA require monitoring where the BLM uses herbicide (USDI 1992a). The District develops and 

the State Office approves Pesticide Use Proposals (PUPs) prior to application; PUPs identify the site, target species, 

herbicide (product and active ingredient) and application rate, adjuvants, and anticipated effects to non-target 

species and susceptible areas. Pesticide applicators fill out Pesticide Application Records within 24 hours of each 

application, documenting environmental conditions at the time of treatment, invasive plant species targeted, 

actual herbicide use, treatment method, applicator and license, and equipment used. Both documents have 

sufficient detail to determine if the BLM and the pesticide applicators met all planning and application 

requirements. The District also documents non-herbicide treatment activities.

Invasive plant treatments conducted by contractors, regardless of treatment method, must also comply with all 

laws, Bureau policies, Standard Operating Procedures and other Protection Measures (see Appendix D), and 

contract specifications. To ensure proper implementation, District project inspectors review contractor operations, 

treatment sites, and treatment records.

As required by existing Standard Operating Procedures, District staff would monitor targeted grazing activities to 

control the timing and intensity of the grazing, incorporating actions such as moving the animals off the site before 

the site is prone to erosion and compaction. The Oregon Department of Agriculture’s Noxious Weed Control 

Program conducts the monitoring of traditional biological control agent populations in coordination with the BLM.

In addition, the West Eugene Wetlands Resource Management Plan requires monitoring. This monitoring focuses 

specifically on monitoring the Resource Management Plan itself. For example, monitoring would assess whether 

implemented projects followed standard operating procedures for herbicide application (USDI 2015a: Appendix B).

Effectiveness Monitoring

Monitoring integrated invasive plant treatments involves revisiting treated sites to assess how the infestation and 

associated plant community have changed over time. Observers look at factors such as the size and density of the 

invasive plant infestation; the amount of colonization by other nonnative plants; the amount of damage or 

mortality in non-target plants; the growth, vigor, and density of native vegetation; and the need for follow-up 

treatments. The District recommends follow-up treatments when an integrated invasive plant management 

treatment has not reduced the target invasive plant infestation to below an acceptable threshold and / or when 

sufficient native vegetation has not reoccupied the site. BLM records infestation and treatment data in BLM’s 

corporate geospatial databases (e.g., NISIMS).

The following example is provided to illustrate how adaptive management and effectiveness monitoring would be 

implemented within the context of invasive plant treatments. Integrated invasive plant management includes a 

process to determine when and where to take action. The Integrated Vegetation Management Manual (USDI 
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2008a:59) describes an adaptive management approach based on clearly identified outcomes, monitoring to 

determine if management actions are being met, and if not, changing management approaches to those that will 

better ensure that outcomes are met.

The Planning section (above) explains that the District manages invasive plants to minimize adverse effects to 

ecological function. Setting treatment priorities is primarily driven by the resources that would be adversely 

affected by the invasive plants (such as habitats for Special Status species). For example, Canada thistle (and 

several other invasive plant species) occurs in an ACEC within proximity of a Special Status plant, the Umpqua 

swertia. The Treatment Key for Canada thistle (Table C-8) shows potential treatment options for this infestation.

Mowing Canada thistle is effective when it is repeated every 3 to 4 weeks over several growing seasons (DiTomaso 

et al. 2013), but can adversely affect desirable intermingled species. Under the action alternatives, aminopyralid

and clopyralid would both be selective treatment methods for Canada thistle intermingled with the Umpqua 

swertia (Dow AgroSciences 2015). In the first year, clopyralid could be used on Canada thistle, applied at the 

rosette stage. As described above, sites are revisited following treatments to assess how the infestation and 

associated plant community have changed over time. This would be done several months after treatments; 

clopyralid begins to kill target plants within two weeks after contact but can take several weeks for complete 

control. Staff conducting the monitoring would evaluate factors such as the size and density of the Canada thistle 

infestation; the amount of colonization by nearby St. Johnswort; the amount of damage or mortality in 

neighboring native species as well as their growth, vigor, and population density; and the need for follow-up 

treatments. If the Umpqua swertia were unharmed by this treatment and were able to colonize the site (instead of 

the St. Johnswort) and the population of Canada thistle was reduced, but not eliminated, another follow-up 

treatment would occur the following spring. However, spring rain accelerates seed growth, and in the spring, the 

Canada thistle seedbank may have begun to produce additional plants. In this case, BLM would use aminopyralid 

to control Canada thistle seedlings during the second year, as it has longer soil residual than clopyralid. If instead 

the original treatment eliminates the Canada thistle but St. Johnswort appear in the following spring, the St 

Johnswort Treatment Key (Table C-24) would direct BLM to use aminopyralid or glyphosate during the second year.

Direct Control Methods

Direct control methods vary by alternative. Selection of a treatment method considers what would be effective for 

each species and what is appropriate for the lands infested (including what nearby resources may be affected). For 

many species, BLM controls small infestations with manual or other non-herbicide treatments. Other species may 

require herbicides to obtain adequate control or minimize ground disturbance. The selection of a treatment 

method is guided by Department of the Interior policy which states “Bureaus will accomplish pest management 

through cost-effective means that pose the least risk to humans, natural and cultural resources, and environment” 

and requires bureaus to “[e]stablish site management objectives and then choose the lowest risk, most effective 

approach that is feasible for each pest management project” (USDI 2007e).

Manual Treatment Methods

Manual treatment methods (such as pulling, digging, chopping, girdling, cutting/lopping, weed wrenches, and 

grubbing) can provide adequate control for some invasive plant species, particularly if the infestation is relatively 

small. These techniques can be extremely target specific and the BLM often uses them to minimize damage to 

adjacent desirable plants. However, manual control methods can be labor and time intensive. Treatments often 

must be conducted several times annually to prevent the invasive plant from re-establishing, which often makes 

manual treatments of invasive plants in remote locations impractical. The BLM uses manual techniques on small 

infestations and / or where a large pool of labor is available. The BLM frequently uses manual treatments in 

combination with other techniques. For example, shrubs can be pulled and cut, and re-sprouts and seedlings can 

be treated with herbicides several weeks or months later (Tu et al. 2001).
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Land managers use manual treatment methods, including hand pulling, rakes, shovels, and bottom barriers / weed 

mats to control infestations of submerged and floating aquatic invasive plants. Weed mats placed on the bottom 

of an aquatic body and held in place with a heavy object (see Figure B-2) for up to a few years can eradicate some 

infestations. (This method would not be used in areas where invasive plants are intermingled with desirable 

vegetation.) Bottom barriers have been used successfully by Rogue River-Siskiyou National Forest to control yellow 

floatingheart at Squaw Lakes.

Figure B-2. Weed Mats, held with Sand Bags (treating Eurasian watermilfoil in Michigan)

© Big Foot Media / The Nature Conservancy

Solarization involves putting a barrier like a plastic sheet, shade cloth, or tarp over an area for up to six months to 

trap heat from solar radiation in order to kill extant vegetation and the associated seed bank. Areas where invasive 

plants are not intermingled with native vegetation create the best conditions for using solarization. Solarization is 

generally used on annual invasive plants because perennials often have deeply buried underground vegetative 

structures such as roots and rhizomes that may resprout. The best solarization will occur on areas where there is 

little or no slope or where the slope has a south or southwest exposure. Solarization prepares sites for seeding and 

planting desirable vegetation.

Mechanical Treatment Methods

Mechanical treatment methods include tilling or disking, string trimmers, chainsaws, propane torches, and 

mowers. Some of these methods (e.g., chainsaws and string trimmer) can be more target-specific than other 

methods. Land managers commonly use string trimmer and mowing methods in recreation, communication, and 

storage and administrative sites to prevent invasive plants from becoming a fire hazard and to maintain clear 

access. Propane torches can be used on invasive plants in the annual grasses, snapdragons, geranium, and 

perennial peas species groups (see Appendix C) growing in parking lots, cobble bars, and other sparsely vegetated 

sites. Propane torches are used to heat plants to boil the water in invasive plant cells, not to consume plants with 

fire.

For aquatic invasive plants, tractors or diver assisted suction harvest (DASH) can be used to remove large 

quantities of invasive plants more quickly than manual methods alone. A diver physically removes (hand-pulls) the 
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targeted plant, being careful to remove the entire root system and to minimize fragmentation. A pump is located 

on the surface (on a boat or the bank of the waterbody), with a four-inch suction hose that the diver uses to 

transport the hand-pulled plant and any root fragments to the surface for collection and disposal. Water and 

sediment is allowed to flow through back into the lake or pond. The objective is not to remove the sediment but to

remove only the target plants to retain visibility in the water for the diver. Tractors can also be used to remove the 

entire root system of aquatic infestations. Aquatic weed harvesters would not be used to mow and remove aquatic 

vegetation.

Competitive Seeding and Planting

When revegetating degraded and disturbed sites, the District uses locally adapted grass and forbs seeds and 

mulches that meet strict weed-free standards. All plant materials are native and genetically appropriate for each 

revegetation site, increasing the probability of successful and persistent native plant establishment that is resilient 

and resistant to invasive plants.

The objective of competitive seeding and planting is to provide a desirable native vegetative component to 

compete with invasive plants in treatment areas. BLM’s Integrated Vegetation Management Handbook states, 

“Diverse, healthy, and resilient native plant communities provide the greatest opportunity to be successful in 

meeting multiple use objectives within BLM. [BLM is required to] set resource management objectives that can be 

met using native species for most situations.” (USDI 2008a:87). Competitive seeding and planting of native, locally 

sourced seeds and plants often occurs in conjunction with other treatments but can also occur independently as a 

measure to prevent invasive plant establishment. The District most commonly seeds by hand spreading to achieve 

a specific density of seed per area. If soil compaction has occurred, raking of the soil may be necessary to allow for 

successful root development. Mulching with weed-free straw often occurs in conjunction with seeding, unless the 

site is difficult to access. Mulch prevents seed herbivory, prevents seeds from blowing or washing off site, protects 

from environmental extremes, retains moisture to increase successful germination, and reduces soil erosion. The 

District plants native species to complement seeding at sites to generate immediate vegetation cover or to include 

native species that do not establish well from seed.

Decisions on which species to include in a planting prescription are based on an evaluation of the surrounding 

native plant community so that the planted site has similar species composition and structure once established. 

Other factors that affect the planting prescription include environmental conditions, availability and condition of 

native plant materials, and budget. Planting prescriptions can include a combination of plant functional groups 

including perennial grasses, annual forbs, and perennial forbs. Most of the seeding prescribed on the District calls 

for grass species. Prescriptions including annual and perennial forbs are usually associated with restoration 

projects. Shrubs and trees are included in some prescriptions.

Prescribed Fire

Prescribed fires are used for invasive plant control, and can be most effective in spring or in fall when conducted 

just before flower or seed set, or at the young seedling or sapling stage. It may also be used in conjunction with 

other methods as a pre-treatment to an herbicide application, such as when the target invasive plants have gone 

to seed and there is a need to remove the seed source or to remove thatch (the mat of un-decomposed plant 

material) in invasive annual grass stands. Like other treatments, timing is critical and is dependent on 

characteristics of the invasive plant, presence of desirable plants, soil moisture, and environmental conditions.

These prescribed fires could be broadcast fires (across monocultures or areas where all species are invasive) or 

machine or hand piled and burned (generally woody species). Treatment areas are calculated by infestation sizes; 

for example, if two acres of woody invasive plant species were collected into a 20 square foot pile, this would 

count as a two-acre treatment.

Propane torches are described above, in the Mechanical Treatment Methods section.
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Biological Treatment Methods

Biological treatment methods involve the intentional use of domestic animals (such as goats or sheep) or biological 

control agents (such as insects, bacteria, or fungi) that weaken or destroy vegetation (USDI 2007d). Biological 

control is used to reduce the targeted invasive plant population to an acceptable background level by stressing 

target plants and reducing competition with desirable plant species.

Biological Control Agents (Biocontrols)

Classical biological control refers to a subset of organisms (or “agents”) that includes plant-eating insects, 

nematodes, mites, or pathogens. Biological control agents are usually acquired from the same ecosystems where 

the target invasive plant originated, and are rigorously tested by the Federal Animal and Plant Health Inspection 

Service (APHIS) Plant Protection and Quarantine Program to ensure that they are host specific and feed only on the 

target plant and not on crops or native flora. Issuance of permits by APHIS for the environmental release of 

nonindigenous invasive plant biological control organisms is considered a Federal action and triggers compliance 

with the Endangered Species Act and the National Environmental Policy Act. The ODA’s Noxious Weed Control 

Program coordinates releases of the agents and monitors populations. Since the biological control agents are not 

successful unless there are enough invasive plants for them to feed upon, typically only large infestations are 

targeted. Often, several biological control agents are used together to reduce the density of undesired vegetation 

but biological controls seldom remove an invasive plant population entirely. Many biological control agents are 

common and widespread on noxious weeds throughout Oregon. For example, the cinnabar moth and tansy flea 

beetle were introduced in the 1960s and persist at background levels in the environment until the tansy ragwort 

population spreads and provides a food source for the biocontrol populations to grow again. The primary factors 

for when and where to release additional biocontrols are infestation size and availability of effective agents for the 

specific site.

Biological control agents (primarily insects) have been used on noxious weeds throughout northwest Oregon. All 

available biocontrol agents that are appropriate for the species present on the District have been released; there 

are no additional releases that are recommended at this time. Table B-1 shows in which counties biocontrols are 

widespread. The Oregon Department Agriculture is currently evaluating several prospective new biological control 

agents for Japanese knotweed and garlic mustard.

Table B-1. Widespread Biological Control Agents on the Northwest Oregon District

Invasive plant (host) Biocontrol

County

Benton

Clackamas

Clatsop

Columbia

Lane

Lincoln

Linn

Marion

Multnomah

Polk

Tillamook

Yamhill

Broom species1

Bruchidius villosus (beetle)         

Exapion fuscirostre (weevil)            

Leucoptera spartifoliella (twig miner)            

Gorse Exapion ulicis (weevil)   

Tetranychus lintearius (spider mite)   

Knapweed species1

Bangasternus fausti (weevil) 

Chaetorellia acroloph (peacock fly) 

Larinus spp. (weevil)       

Metzneria paucipunctella (moth)  

Sphenoptera jugoslavica (root borer)  

Terellia virens (fly) 
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Invasive plant (host) Biocontrol

County

Benton

Clackamas

Clatsop

Columbia

Lane

Lincoln

Linn

Marion

Multnomah

Polk

Tillamook

Yamhill

Urophora quadrifasciata (fly)         

Purple loosestrife

Galerucella spp. (beetle)         

Nanophyes marmoratus (weevil)    

Rush skeletonweed Eriophyes chondrillae (gall mite) 

Puccinia chondrillina (rust fungus) 

St. Johnswort Aplocera plagiata (inchworm)      

Chrysolina spp. (beetle)            

Tansy ragwort

Botanophila seneciella (fly)            

Longitarsus jacobaeae (flea beetle)            

Tyria jacobaeae (cinnabar moth)            

Thistle species1 Cheilosia corydon (fly) 

Rhinocyllus conicus (weevil)            

Thistles and knapweed 

species1 Urophora spp. (fly)      

Toadflax species1 Brachypterolus pulicarius (beetle) 

Gymnetron antirrhini (weevil) 

1. May include one or more species in this group.

Targeted Grazing

Targeted grazing6 is the purposeful application of a specific species of livestock at a determined season, duration, 

and intensity, to accomplish defined vegetation or landscape objectives (ASI 2006). The basic goal of targeted 

grazing is to give the desired plants a competitive advantage over the target invasive plant or plants. In general, 

goats and sheep eat broadleaf plants. Grazing can be seasonally timed for when the target plant is most palatable 

to livestock and to minimize effects to non-target plants and surrounding resources. Typically, a full-time herder or 

fencing is required to keep the grazing focused on the target areas and species. Employing grazing prescriptions 

may be particularly useful in areas with limited access, steep slopes, or where the most effective herbicide for a 

particular plant species cannot be applied (e.g., a non-aquatic herbicide application near water). Although targeted 

grazing with livestock can reduce invasive plant abundance and / or vigor at a particular site, grazing rarely, if ever,

eradicates invasive plants. As with many other treatments, targeted grazing with livestock can be most effective 

when used in combination with other treatments (USDI 2010a:75).

Herbicide Treatment Methods

Herbicides used on BLM-administered lands must be approved by the BLM National Office, and must, by policy, be 

subject to detailed ecological and human health risk assessments (see Appendix F, Herbicide Risk Assessment 

Summaries) for wildland applications to help satisfy the requirements of NEPA (USDI 2010a:37). However, BLM 

practice allows for limited and controlled use of herbicides that do not have Risk Assessments on demonstration 

plots up to 5 acres in size, with a maximum of 15 acres per field office7

. Approval to use an herbicide for research 

 6 Also referred to as directed livestock grazing or prescribed grazing.

7 Not an annual limit. This 15-acre limit could only be exceeded by the issuance of ecological and human health Risk 

Assessments, done or adopted by the BLM, and results evaluated through programmatic NEPA analysis done at the National or 

State level.
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and demonstration is provided by the BLM National Office after an initial evaluation of Federal Insecticide, 

Fungicide and Rodenticide Act registration materials and associated risk assessments (USDI 2010a:478)8

. 

Herbicides analyzed in this EA are shown in Table B-2, Herbicide Information, and Table B-3, Herbicide 

Characteristics. Herbicides are utilized:

• on pure stands of a single invasive plant species where desirable and non-target plants are scarce or absent;

• for rhizomatous invasive plant species that would otherwise require repeated cutting or pulling for control;

• on plants whose characteristics make them difficult or unfeasible to remove with non-herbicide methods;9

• in areas where non-herbicide methods are cost prohibitive;

• in areas where non-herbicide methods have unacceptable adverse effects to native plants;

• in areas where considerable soil disturbance is not acceptable;

• for species located in remote or limited access areas where non-herbicide methods are not feasible;

• in combination with other control treatments (for example, woody species like gorse can be controlled by 

cutting stems close to the ground in the fall and then spraying the cut stumps with an herbicide registered for 

this use).

BLM only applies herbicides to lands and uses for which they are labeled and only by certified or licensed 

applicators or persons working under their direct supervision (USDI 2010a:85). Applicators complete a Pesticide 

Application Record within 24 hours of the application to document environmental conditions at the time of 

treatment as well as actual herbicide use. This record, kept in District files for 10 years, helps the BLM duplicate 

successes, change procedures to improve effectiveness, and understand when and if unintended effects occur.

Herbicide products (brands), as well as adjuvants (used to enhance the effectiveness of the herbicide) must be on 

the BLM lists of approved herbicides and adjuvants at the time of application. The current lists are included in 

Appendix E, Herbicides Formulations and Adjuvants. For applications with a potential to enter streams or other 

waterbodies, herbicides are limited to aquatic formulations. Applicators use aquatic-approved adjuvants10 for 

applications with a potential to affect federally listed and Bureau Sensitive fish.

Herbicides are primarily applied to plant foliage, but some herbicides may be applied to the soil (see Table B-2 for 

information about point of application by herbicide). These treatments are usually done only in small areas (see 

Table A-1 for a summary of invasive plant infestation sizes). Herbicide applications can be done with a backpack 

sprayer (see Figure B-3). Sprayers are generally non-motorized and are pressurized by a diaphragm or piston-style 

pump. Spot treatments using hand-held sprayers are attached to vehicle-mounted trucks, utility vehicles (UTVs), 

boats, or on horseback. In spot treatments, the hand-held sprayer can target specific plants, so that effects to nontarget species can be kept to a minimum. Broadcast treatments would also occur under the action alternatives, 

although this would happen rarely (less than five percent of the time). The District would usually do these 

treatments with a handheld sprayer. Broadcast treatments using a boom would most often occur in the West 

Eugene Wetlands or in special plant communities (such as a meadow or grassland). Broadcast treatments would be 

done with selective herbicides that would not harm non-target plants or these treatments would happen on larger 

monocultures of invasive plants (larger than 300 square feet). All broadcast treatments (with a handheld sprayer 

or a boom) would be specifically noted on the Annual Treatment Plan. Interdisciplinary team review of Annual 

Treatment Plans with broadcast treatments would include natural resource specialists with expertise in soil and 

hydrology. The District has not and would not use aerial applications to control non-native invasive plants.

Other ground-based herbicide application methods that the District could use include:

• basal bark treatments (where herbicides are applied to the bark of woody plants with a backpack sprayer 

or handheld spray bottle);

 8 If research and demonstration results appear favorable, then the BLM further considers the herbicide for general approval 

after human health and ecological Risk Assessments are undertaken, and the results are evaluated through the NEPA process.

9 For example, Canada thistle root fragments readily resprout and some plants can be injurious to workers attempting to 

manually remove them.

10 These “approved adjuvants” shown in Appendix E are indicated in the ARBO II column of Table E-3. These adjuvants were 

analyzed in the U.S. Fish and Wildlife Service and National Marine Fisheries Service ARBO II (USDI 2013a, NMFS 2013).
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• frill or “hack and squirt” (where herbicides are applied to a continuous downward cut around a woody 

plant that extends into the sapwood);

• wipers (where herbicides are wiped directly onto the plant or to cut stems and stumps); or 

• injecting herbicides into the inner bark. 

Figure B-3. Ground-Based Herbicide Applications with Backpack Sprayer

Stressors such as imperfect growing conditions (too wet, too dry, or poor soil nutrients) may prevent the herbicide 

from acting optimally. In addition to the effects of the herbicides themselves, the application methods may have 

unintended adverse consequences. Similar to manual and mechanical treatments, personnel and equipment may 

trample vegetation and disturb soil, which can cause further spread of invasive plants. However, herbicide 

treatments are less likely to require numerous retreatments. In the Oregon FEIS, overall treatment efficacy was 

estimated at 30 percent if herbicides were not used11.

 11 See Chapter 2 and Issue 1 in Chapter 3 of this EA for information treatment efficiency under each alternative.
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Table B-2. Herbicide Information

Herbicide: Representative Trade Names1

Common Targets

Selective to Plant Types

Pre / post emergent

Point of application

Areas Where Registered Use is 

Appropriate3

Application Rate4

(lbs. / acre / year) Alternatives

Rangeland

Forest and Woodland

Riparian / Seasonal Wetland

Aquatic / Wetland

Oil, Gas, & Mineral Sites

Rights-of-Way

Recreation & Cultural Sites

Typical Max2

No Action

Alternative 2Alternative 3

2, 4-D: Many, including Amine 4, HardBall, Unison, Saber, and 

Aqua-Kleen

Broadleaf plants

broadleaf

Post

Foliar

Annual and Perennial Species

      1 (1.9 or 29)   

Woody Species / Floating and Emerged Aquatic Species

   3    2 (4)  

Submerged Aquatic Species – treatments in water

3 5.4 (10.8) 

Submerged Aquatic Species – bottom treatments

3 19 (38) 

Aminopyralid: Milestone

Starthistle, St. Johnswort, thistles, knapweeds

broadleaf

Post

Foliar

      0.078 0.11  

Chlorsulfuron: Telar XP

Perennial mustards, purple foxglove, houndstongue

broadleaf

Pre and early post

Foliar

     0.047 0.141  

Clopyralid: Transline, Stinger, Spur

Knapweed, hawkweed, biennial thistles, starthistles 

broadleaf

Post

Foliar

      0.35 0.5  

Dicamba: Vanquish, Banvel, Diablo, Vision, Clarity

Perennial mustards, biennial thistles, field bindweed 

broadleaf, woody plants

Pre and post

Foliar

     0.3 27   

Diflufenzopyr + Dicamba: Overdrive, Distinct

Field bindweed, oxeye daisy, St. Johnswort

broadleaf

Post

Foliar

    0.2625 0.35  

Dicamba 0.1875 0.25

Diflufenzopyr 0.075 0.1

Fluridone: Avast!, Sonar AS

Aquatic plants

submerged plants

Post

Aquatic

 0.15 (1.3) 
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Herbicide: Representative Trade Names1

Common Targets

Selective to Plant Types

Pre / post emergent

Point of application

Areas Where Registered Use is 

Appropriate3

Application Rate4

(lbs. / acre / year) Alternatives

Rangeland

Forest and Woodland

Riparian / Seasonal Wetland

Aquatic / Wetland

Oil, Gas, & Mineral Sites

Rights-of-Way

Recreation & Cultural Sites

Typical Max2

No Action

Alternative 2Alternative 3

Fluroxypyr: Comet Selective, Vista XRT

Mustards, spurge, blackberry

broadleaf

Post

Foliar

      0.26 0.5  

Glyphosate: Many, including Rodeo, Mirage, Roundup Original, 

Mad Dog Plus, and Honcho

Grasses, trees and shrubs, yellow flag iris

non-selective

Post

Foliar

   3    2 3 or 75, 6   

Hexazinone: Velpar DF

Grasses

grasses, broadleaf, woody plants

Pre and post

Foliar

     2 46  

Imazapic: Plateau, Panoramic 2SL

Annual grasses

some broadleaf and grasses

Pre and post

Soil

      0.0313 0.1875  

Imazapyr: Arsenal, Stalker, Habitat, Polaris

Trees and shrubs, yellow flag iris

non-selective

Pre and post

Foliar

       0.45 1.507  

Metsulfuron methyl: Escort XP, Patriot, PureStand

Perennial mustards, St. Johnswort, biennial thistles 

broadleaf

Pre and post

Foliar

      0.03 0.157  

Picloram: Triumph 22K, OutPost 22K, Tordon 22K

Leafy spurge, field bindweed, knapweed, St. Johnswort, 

starthistles, biennial thistles 

broadleaf, woody plants

Pre and post

Foliar

     0.35 1   

Rimsulfuron: Matrix SG

Annual grasses

annual grasses

Pre and post

Soil

      0.0469 0.0625  

Sulfometuron methyl: Oust XP, Spyder

Annual grasses

non-selective

Pre and post

Foliar

     0.14 0.38  

Triclopyr: Garlon 3A, Renovate 3, Element 4, Vastlan

Purple loosestrife, blackberry, trees and shrubs

broadleaf, woody plants

Post

Foliar

   3    1 (10)  
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Herbicide: Representative Trade Names1

Common Targets

Selective to Plant Types

Pre / post emergent

Point of application

Areas Where Registered Use is 

Appropriate3

Application Rate4

(lbs. / acre / year) Alternatives

Rangeland

Forest and Woodland

Riparian / Seasonal Wetland

Aquatic / Wetland

Oil, Gas, & Mineral Sites

Rights-of-Way

Recreation & Cultural Sites

Typical Max2

No Action

Alternative 2Alternative 3

Proposed For Research and Demonstration

Fluazifop-P-butyl9: Fusilade DX

Perennial grasses

grasses

Post

Foliar

   

Single app. 0.1 to 0.375.

Maximum annual 

application 1.1258

 

Sethoxydim: Poast, Torpedo, Ultima, Vantage, Conclude, and 

Rezult

Perennial grasses

grasses

Post

Foliar

   0.310 0.37510  

1. See Table E-2, Herbicide Formulations Approved for use on BLM-Administered Lands, in Appendix E for the full list of herbicide trade names approved for use on lands managed by the BLM in Oregon, including 

formulations with two or more active ingredients.

2. Maximums are determined by herbicide product label and information analyzed in Risk Assessments. In cases where these two rates differ, the lower of the two rates is the maximum that can be applied on BLMadministered lands. Parentheticals denote herbicides that are limited by PEIS Mitigation Measures to typical application rates where feasible.

3. Different registrations are listed on the herbicide product label. Some types of registration (e.g., aquatic) require extensive additional testing with the EPA; the lack of registration for an area may indicate that a product 

has not completed that registration, not that there would be a risk. Some herbicide products may not be registered for use in an area, even though the active ingredient may have registration (e.g., in aquatic habitats, only 

certain formulations of glyphosate, the amine formulation of 2,4-D, and the trimethylamine (TEA) salt formulation of triclopyr are registered for aquatic use).

4. Actual application rates can be found in Appendix C, Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

5. Three lbs. / acre acid equivalent for the No Action Alternative and 7 lbs. / acre under the action alternatives. The existing NEPA analyses on the District relies on a 1985 glyphosate Risk Assessment that analyzes 

glyphosate at 3 lbs. / acre acid equivalent, based on the maximum application rate on a Rodeo © label. The 2011 glyphosate Risk Assessment (SERA 2011a) analyzes a maximum rate of 7 lbs. / acre. Maximum rates on 

formulated product labels listed in Table E-2 (Appendix E) range from 7 lbs. / acre to 14 lbs. / acre.

6. PEIS Mitigation Measures include “where practical, limit glyphosate and hexazinone to spot applications in grazing land and wildlife habitat areas to avoid contamination of wildlife food items”

7. Mitigation Measures adopted by the Oregon Record of Decision state, “where there is a potential for herbivore consumption of treated vegetation, apply dicamba, imazapyr, and metsulfuron methyl at the typical, rather 

than maximum, application rate to minimize risks.”

8. Information from SERA (2014). BLM maximum and typical rates have yet to be calculated.

9. 1.9 lbs. / acre for the No Action Alternative and 2 lbs. / acre under the action alternatives. 

10. As described in the sethoxydim Risk Assessment (SERA 2001). BLM maximum and typical rates have yet to be calculated.
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Table B-3. Herbicide Characteristics

Herbicides analyzed for Research and Demonstration

Fluazifop-P-butyl Fluazifop-P-butyl and sethoxydim are effective on annual and perennial grasses, but do not affect 

Sethoxydim broadleaf plants.

Herbicides approved for use on BLM-administered lands

2,4-D

2,4-D is effective on a wide range of broadleaf invasive plants while not affecting most grasses. 2,4-D 

can help inhibit seed production, prevent herbicide resistance, and effectively treat multiple invasive 

plant species when a variety are encountered in a particular treatment area. While having additional 

herbicides available can allow for more target specific control, having one herbicide that controls a vast 

range of vegetation can be beneficial in areas dominated by a variety of invasive broadleaved plants. In 

addition, adding a small amount of an amine formulation of 2,4-D to a tank mix can often improve the 

effectiveness of the other herbicides and reduce the likelihood of a population developing herbicide 

resistance. The amount of 2,4-D used in combination with other herbicides would vary, based on these 

factors.

2,4-D is formulated as an amine or an ester. Esters have higher vapor pressures than amines, which 

results in increased volatilization. On the Northwest District, amine formulations would be preferred. 

The use of ester formulations is not anticipated and would not be permitted near surface water or 

conduits to surface water.

Aminopyralid

Aminopyralid is selective for broadleaf species, particularly members of the Asteraceae (sunflower) and 

Fabaceae (pea) families and is also effective on certain species in the Apiaceae (carrot), and 

Polygonaceae (knotweed) families. It is effective at controlling knapweed and various thistles 

(DiTomaso and Kyser 2006, Enloe et al. 2008, Bell et al. 2012). It is an alternative to other growth 

regulator herbicides that are commonly used on broadleaf invasive plants, such as picloram, clopyralid, 

2,4-D, and dicamba. Studies have also found aminopyralid to be as or more effective than the currently 

approved growth regulator herbicides at lower application rates (Enloe et al. 2007, 2008; Bell et al. 

2012). Aminopyralid has a higher specific activity than other growth regulator herbicides, so less of it 

needs to be used to achieve the same result (Iowa State University 2006). It is more effective than 

clopyralid on tough to control members of the Asteraceae family. In mixtures with other active 

ingredients like metsulfuron methyl, it can be used on hard-to-control species like poison hemlock 

(DiTomaso et al. 2013).

Chlorsulfuron

Chlorsulfuron is especially effective on broadleaf plants such as mustards, houndstongue, and thistles. It 

is often mixed with 2,4-D to reduce the likelihood of developing plant resistance and to deter seed 

production. Some grass species can be damaged by this herbicide, particularly wet meadow grass 

species.

Clopyralid

Clopyralid targets many of the same species as picloram, but is more selective. It is particularly effective 

on knapweeds and Canada thistle, while minimizing risk to surrounding desirable brush, grass, and 

trees. 

Dicamba

Dicamba provides control right up to seed set, which extends the treatment window. It is often used in 

a tank mix with 2,4-D amine. It is effective on invasive broadleaves but offers minimal residual control. 

It is an option where resistance to sulfonylureas is a concern. It can reduce seed set in mustards but 

does not provide effective control. 

Dicamba + 

Diflufenzopyr

Diflufenzopyr + dicamba would be used for many of the same species as dicamba. Used where

resistance to sulfonylureas is a concern. It is applied in the fall when native plants are dormant. Often 

used on roadsides. 

Fluridone

Fluridone is an aquatic herbicide that requires prolonged plant contact, so it can only be used on 

aquatic plants in still water. It is used primarily post-emergent to control submerged aquatic vegetation. 

To achieve effective control a minimum of 45 days (up to 90) of herbicide contact is required. 

Fluroxypyr

Fluroxypyr is effective on annual and biennial invasive plants. It would be used to manage teasel, 

shining geranium, or herb Robert. Fluroxypyr is an option for addressing invasive plants that are 

resistant to herbicides with different modes of action. Its uses would likely include administrative sites 

and rights-of-way where resistance to currently approved herbicides could be a problem.

Glyphosate

Glyphosate is used on broadleaf invasive plants and woody species and has been used to treat nearly all 

of the mapped noxious weed species on the District. However, it is a non-selective herbicide and can 

harm desirable plants. The overall use of glyphosate would decrease in aquatic / riparian areas if 

additional aquatic formulations were available since glyphosate and 2,4-D have been the only two 

aquatic herbicides available to the District. Aminopyralid would replace glyphosate for many terrestrial 

broadleaf species. The BLM does not use glyphosate formulated with polyoxyethyleneamine (POEA).
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Imazapic

Imazapic is a broad-spectrum herbicide for broadleaf and grass species, but is particularly effective on 

invasive annual grasses such as soft brome and medusahead. It is selective for these grasses at low

rates, leaving the perennial herbaceous species critical for restoration unharmed. It is applied before 

plants have emerged or to small rapidly growing plants. If heavy thatch or leaf litter is present, herbicide 

effectiveness is reduced.

Imazapyr

Imazapyr is very effective on brushy and woody species such as brooms, blackberry, hawthorn, and 

tree-of-heaven. It is also used to treat perennial grasses and loosestrife. Imazapyr may be used for the 

control of aquatic invasive plants like parrot feather, flowering rush, hydrilla, and yellow flag iris in and 

around standing and flowing water, as well as in riparian / wetland settings. 

Metsulfuron methyl

Metsulfuron methyl has similar targets and effects as chlorsulfuron. It could be used on the mustard 

family, as well as thistles. It can be used in combination with aminopyralid to treat species in the 

carnation, carrot, mustards, knapweed species groups (such as bladder campion, poison hemlock, garlic 

mustard and yellow starthistle). 

Picloram

Picloram is effective on knapweeds, hawkweed, leafy spurge, and thistles, and provides good residual 

control. Appropriate at sites where soils are not sandy or gravelly. Aminopyralid and clopyralid target 

many of the same species and are more selective. Picloram is a restricted used herbicide.

Rimsulfuron

Rimsulfuron is effective against annual grasses in the fall pre-emergence, or post emergence in the fall 

or spring when soil temperature is cool and rainfall is available to activate the herbicide. It provides a 

longer window of control than imazapic, although it must be used at the highest label rates for effective 

spring applications. Rimsulfuron has a one-year grazing restriction. It would not be applied near water. 

Sulfometuron 

methyl

Like imazapic, sulfometuron methyl is effective on medusahead rye and can be selective for annuals at 

low rates. It has a shorter half-life than imazapic, which speeds restoration efforts. At typical and 

maximum rates, sulfometuron methyl controls many annual and perennial grass and broadleaf species. 

At low rates, it is safe on perennial grasses while controlling forbs and annual grasses. Sulfometuron 

methyl has a one-year grazing restriction (although it is not registered for use in rangelands).

Triclopyr

Triclopyr is effective on woody plants, and would be used on blackberry, brooms, gorse, and other trees 

and shrubs. It may also be used on select broadleaf species such as annual peas and buttercups. The 

aquatic formulations are also the most effective herbicide for treatment of purple loosestrife and other 

aquatic species. Triclopyr BEE, the ester formulation (butoxyethyl ester), is more effective at smaller 

doses, but is more toxic to fish (and as a result, triclopyr BEE cannot be used in aquatic or riparian 

habitat). It is often used as a cut-stump treatment.

Resistance and Rotation

Herbicide resistance12 is the evolved ability of an invasive plant population to survive an herbicide application that 

was previously known to control the population. Where invasive plant infestations have been sprayed annually 

with the same herbicides with low likelihood of effective control, a concern is that plant populations could become 

herbicide resistant. Most plant populations showing herbicide resistance are in agriculture settings; however, 

resistance has been documented in wildland vegetation management settings and invasive plant programs 

(University of Idaho 2011). Resistance can result from repeated use of the same herbicides, or several herbicides 

with the same site of action13.

The use of additional herbicides would help prevent herbicide resistance by adding chemicals that control the 

plants through different modes and sites of action. More effective rotation of herbicides (see Table B-4), when 

coupled with integrated invasive plant management, would help prevent the development of herbicide resistance. 

 12 Naturally resistant plants occur within a population in extremely small numbers (somewhere between 1 in 100,000 to more 

than 1 in 1,000,000). They differ slightly in genetic makeup from the original populations, but they remain reproductively 

compatible with them. The repeated use of one herbicide, or of herbicides that kill the plants the same way (same mode or site 

of action), allows these few plants to survive and reproduce. The number of resistant plants then increases in the population

until the herbicide no longer effectively controls it. 13 Site of action is defined as the specific process in plants that the herbicide disrupts to interfere with plant growth and 

development. Mode of action is defined as all herbicide interactions with the plant, from application to final effect. The mode 

of action involves absorption into the plant, translocation or movement in the plant, metabolism of the herbicide, and the 

physiological plant response.
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Many product labels for the acetolactate synthase (ALS)-inhibitors (such as chlorsulfuron and metsulfuron methyl) 

recommend tank-mix partners and / or sequential herbicide applications that have different modes of action.

Table B-4. Guide for Herbicide Rotation1

Herbicide 

Group

Herbicide Chemical 

Family

Herbicide Common 

Name Resistant Plants States with Resistant Plants

ACCase 

Inhibitors

Cyclohexanediones Sethoxydim Italian ryegrass Idaho, Oregon

Aryloxyphenoxypropanoates Fluazifop-P-butyl cheatgrass Oregon

ALS Inhibitors

Imidazolinones Imazapic none none

Imazapyr none none

Sulfonylureas

Chlorsulfuron

prickly lettuce

kochia

Russian thistle

Italian ryegrass

stinking chamomile 

littlepod falseflax

Idaho, Oregon, Washington

Idaho, Oregon, Washington

Idaho, Oregon, Washington

Oregon

Idaho, Washington

Oregon

Metsulfuron methyl

prickly lettuce

kochia

Russian thistle

littlepod falseflax

Idaho, Oregon

Oregon

Oregon

Oregon

Rimsulfuron none none

Sulfometuron methyl none none

Synthetic auxins

Phenoxyacetic acids 2,4-D prickly lettuce Washington

Benzoic acids Dicamba kochia

prickly lettuce

Idaho

Washington

Pyridines

Aminopyralid none none

Clopyralid none none

Fluroxypyr none none

Picloram yellow starthistle Washington

Triclopyr none none

Photosystem II 

inhibitors As-triazines Hexazinone shepherd’s purseItalian ryegrass Oregon

ESPS synthase 

inhibitors Glycines Glyphosate Italian ryegrasskochia

Oregon

Oregon, Idaho

To avoid selecting for herbicide-resistant invasive plants, rotate to a different group every year if possible. Avoid using herbicides from the same 

group more than once every three years.

1. Adapted from Herbicide-Resistant Weeds and Their Management (University of Idaho 2011), which did not include fluridone. However, 

plants have been shown to develop resistance to repeated fluridone use (ENSR 2005c).
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98

Appendix C: Treatment Key, Invasive 

Plant Sites, and the Annual 

Treatment Plan

Tables C-1 through C-27 contain information about invasive plant infestations and their potential treatments under 

each alternative (the Treatment Key). The District arranged species of invasive plants that would be treated in the 

same manner into groups. Information about which plants species are in which group and the locations of those 

groups are included in the first part of each table and treatment methods are included in the second part. Groups 

include existing invasive plant sites (species known on the District), as well as species not yet found on the District 

that may spread to the District in the future. Noxious weeds are listed in bold. (Note that invasive plants that are 

not listed as noxious weeds cannot be treated with herbicides under the No Action Alternative.) Acres are gross 

acres (see Figure A-1 in Appendix A) and acres are rounded to two digits; acres that are shown as 0.00 are smaller 

than 0.005 acres. 

The Treatment Key portion of each table shows treatment options under each alternative, as well as 

considerations for when treatment methods may be used. Most treatments are suggested by Weed Control in 

Natural Areas in the Western United States (DiTomaso et al. 2013). For each species group, the preferred 

treatment method is listed first, with second and third choices (and so on) listed subsequently. Factors that could 

lead to the preferred (and subsequent) methods not being appropriate are listed in the Treatment Considerations

column, and includes information such as plant life cycle, soil types, plant resistance to herbicides, infestation size, 

herbicide selectivity to neighboring desirable vegetation, weather conditions, and protection measures or label 

restrictions that limit areas an herbicide could be used in. The Treatment Considerations column includes common 

treatment considerations and is not an exhaustive list. Application rates are shown as lbs./acre and are averages. 

Actual formulations may vary slightly, depending on mixes of herbicides or adjuvants, timing, and other factors 

that could increase effectiveness on individual plants. Lbs./acre are calculated from rates per acre on the label, and 

can vary based on formulation. Typical and maximum application rates are listed on Table B-2, Herbicide 

Information. Lbs./acre in bold are at or above the typical application rate. Red indicates lbs./acre at the maximum 

application rate. Rates are rounded to two digits; e.g., the max rate of imazapic is 0.1875 lbs./acre is shown as 0.19 

in this table. In some cases, application rate is listed as (minimal), which indicates that the rate would be 1/10th or 

less of the typical application rate.

As described under the alternatives in Chapter 2, competitive planting and seeding may also occur to revegetate 

areas in conjunction with other treatment methods. In addition, prescribed fire may also occur in any group.

Within each species group, area or field office, and by alternative, the Percent of Acres where Treatment Would be 

Used column adds up to 100 percent and shows how often a treatment method would be used when a species 

infestation is targeted for treatment. For example, under the No Action Alternative in the Tillamook and Marys 

Peak Field Offices, annual grasses would be controlled manually 50 percent of the time, mechanically 5 percent of 

the time, with glyphosate 10 percent of the time, propane torch less than 1 percent of the time, and 35 percent of 

the time, there would be no adequate control method. These estimates are generally based on treatment of 

known sites. These percentages are based on acres treated, not on number of sites treated. For example, if 20 oneacre sites had invasive plants that were manually pulled, and one 20-acre site is sprayed with imazapyr, manual 

and imazapyr would both be 50 percent each. Under the No Action Alternative, areas (e.g., field offices) are 

grouped if similar treatments occur in both areas. For example, Tillamook and Marys Peak Field Offices are both 

covered by the Westside Salem Integrated Non-Native Plant Management Plan EA (USDI 2008d) and would use the 

same treatment methods on the same species.
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It should be noted that the District would not necessarily treat all invasive plants or the infestations listed in these 

tables. The District would treat approximately 2,000 to 6,000 gross acres (on average 3,000 gross acres) annually 

and these acres would be selected based on type of species, location, and potential for spread. Further 

information can be found in Appendix B, in the Prioritizing Areas for Treatment section. Many of the species 

groups include a row for “no adequate control” after the listed treatment methods. This indicates the percent of 

acres targeted for treatment that the District cannot control because adequate control methods are unavailable or 

unfeasible and treatments would not be attempted even in high priority circumstances.

A summary of treatment methods and species groups can be found in Table C-28, Summary of Treatment Options 

Available under One or More Alternatives, by Species Group. This year’s proposed invasive plant treatments can be 

found in Table C-29, Annual Treatment Plan.
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Table C-1. Annual Grasses: Locations and Treatment Key

Annual Grasses Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook 

Field Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Medusahead

Taeniatherum caput-medusae 6 4.50 6 4.50 No Limited distribution. In clay soils and open disturbed areas.

North Africa grass

Ventenata dubia 0.10 0.10 No Roadsides, open areas, grasslands, plantations

Soft brome

Bromus hordeaceus 22 1.98 22 1.98 No Forest, woodland, roadside, riparian

Wild oat

Avena fatua 6 0.08 6 0.08 No Meadows, fields

Totals 0.10 28 2.06 6 4.50 34 6.56 0.10

Annual Grasses Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 50% 50% 50% 5% Small sites can be controlled through hand-pulling.

Mechanical control NA 5% 5% 5% 5% 5% 5% Mowing at the bolt to early flowering stage may help to suppress plants. However, 

mowing after seed set will disperse seeds.

Imazapic 0.06 to 0.12 NA NA NA NA NA 45% Apply at the pre-emergent stage in the fall, when desirable grasses and forbs are 

dormant.

Rimsulfuron 0.03 to 0.06 NA NA NA NA NA 35% Apply pre-emergence to early post-emergence when target plants are young and 

actively growing. Perennial grasses are tolerant to fall applications.

Glyphosate <3.00 NA NA 10% 10% 10% 1% Apply at the seedling stage. Since it is non-selective, minimize exposure to nontarget plants. 

Fluazifop-P-butyl 0.38 NA NA 1% NA NA 1%

Research and Demonstration herbicide. See Special Local Needs Label (FIFRA Sec 

24, OR-120016). Apply to actively growing grasses. Repeat applications may be 

needed. 

Sulfometuron 

methyl 0.05 to 0.09 NA NA NA NA NA 1% Apply pre-emergence or early when plants are germinating and actively growing. May be used in seasonally wet areas when water is not present. 

Hexazinone 0.75 NA NA NA NA NA 1% Apply pre-emergence or early post emergence. Use primarily on road rights-ofway.
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Annual Grasses Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Sethoxydim 0.30 NA NA NA NA NA 1% Research and Demonstration herbicide.

Targeted grazing 

(cattle) NA NA NA NA 0% 0% 1%

Would be used only in limited situations, primarily in meadows from late fall to 

early spring. Would be used to reduce biomass and seed production of grasses. 

Would be followed by broadcast applications of imazapic or rimsulfuron at some 

heavily infested sites. Would often be followed by competitive seeding with native 

grasses and forbs.

Propane torch NA NA NA 1% <1% <1% 4% Most effective on small plants. Use only on infestations on non-flammable 

substrate (e.g., sand, gravel, concrete).

No adequate 

control methods NA 45% 45% 13% 35% 35% 0%

Table C-2. Annual Peas: Locations and Treatment Key

Annual Peas Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette Field 

Office

Siuslaw Field Office Tillamook 

Field Office

Marys Peak 

Field Office

Cascades

Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Sweetclover

Melilotus offincinalis 71 36.14 375 318.60 74.31 1.00 446 354.74 75.31 In areas1 Meadows, prairies, open woodlands, waste areas

1. Marys Peak Field Office

Annual Peas Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 75% 75% 25% 75% 75% 25% Hand-pulling can be used on small infestations or isolated plants, as long as belowground tissue is also removed (to prevent re-sprouting).

Aminopyralid 0.05 to 0.11 NA NA 35% NA NA 35% Apply in spring before flowering.

Clopyralid 0.09 to 0.19 NA NA 15% NA NA 15% Apply in spring before flowering.

Triclopyr 2.00 NA NA 15% NA NA 15% Apply in spring when plants are rapidly growing.
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

102

Annual Peas Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Glyphosate <3.00 NA NA 10% NA NA 5% Apply in spring before flowering.

2,4-D 1.00 NA NA NA NA NA 5% Apply in spring to actively growing plants, particularly at bud to flower.

Picloram 0.50 to 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Evaluate soil, slope, and proximity to water when considering this herbicide. Works 

best when plants are growing rapidly in spring before full bloom or in late summer 

to early fall.

Mechanical control NA <1% <1% <1% <1% <1% <1%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple 

treatments/year for effective weed control.

Targeted grazing 

(goats or sheep) NA NA NA <1% <1% <1% <1% Targeted grazing can reduce the biomass of invasive plants. Fencing or herding required.

No adequate 

control methods NA 25% 25% 0% 25% 25% 0%

Table C-3. Aquatic Species: Locations and Treatment Key

Aquatic Species Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook 

Field Office

Marys Peak 

Field Office

Cascades

Field Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Eurasian watermilfoil

Myriophyllum spicatum Currently unknown on District Aquatic

Flowering rush

Butomus umbellatus Currently unknown on District Aquatic

Fragrant water lily

Nymphaea odorata Currently unknown on District Aquatic

Hydrilla

Hydrilla verticillata Currently unknown on District Aquatic

Parrot feather

Myriophyllum aquaticum 3 0.32 3 0.32 No Aquatic, river
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

103

Aquatic Species Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook 

Field Office

Marys Peak 

Field Office

Cascades

Field Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Water primrose

Ludwigia hexapetala Currently unknown on District Aquatic in shallow slow-moving water along rivers, ditches, ponds

Floating water primrose

Ludwigia peploides Currently unknown on District Aquatic in shallow slow-moving water along rivers, ditches, ponds

Yellow floating heart

Nymphoides peltata Currently unknown on District Aquatic

Aquatic Species Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative and Alternative 2

Alternative 

3

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA NA NA NA NA NA 50% Weed mats, held in place with a heavy object, can be used to eradicate infestations. 

Hand pulling can be effective on small infestations.

Glyphosate (Minimal) NA NA NA NA NA 10% Non-selective. Likely to be used on smaller infestations where exposure to non-target 

plants can be minimized.

Triclopyr (Minimal) NA NA NA NA NA 35% Emergent shoots of parrot feather are difficult to “wet” due to dense waxy cuticle

and a surfactant should be used. Broadleaf selective (more selective than 2,4-D).

Imazapyr (Minimal) NA NA NA NA NA 4% Slow acting systemic. Non-selective.

Mechanical control NA NA NA NA NA NA 1% Diver assisted suction harvest or tractor. Tractor can be effective but difficult to get 

entire plant.

Fluridone (Minimal) NA NA NA NA NA <1%

Use various formulations (variable release-rates) or repeated applications for five to 

seven weeks. Would only be applied in ponds, lakes, and other non-flowing water 

bodies. Non selective.

2,4-D (Minimal) NA NA NA NA 0% <1%

Emergent shoots of parrot feather are difficult to “wet” due to dense waxy cuticle 

and a surfactant should be used. Broadleaf selective; use infestations where exposure 

to non-target plants can be minimized.

No adequate 

control methods NA 100% 100% 100% 100% 100% 0%
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

104

Table C-4. Biennial Thistles: Locations and Treatment Key

Biennial Thistles Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bull thistle

Cirsium vulgare 1,442 1,191.40 1,390 1,425.62 341.05 1,824.70 594 2,047.54 1,574 194.14 5,000 4,858.70 2,165.75 Yes Roadside, open forest, clearings

Common burdock

Arctium minus 21 24.15 6.16 21 24.15 6.16 Yes Open forests, roadside, riparian areas

Distaff thistle

Carthamus lanatus Currently unknown on District Roadsides, disturbed openings

Italian thistle

Carduus pycnocephalus Currently unknown on District Urban, grassland

Milk thistle

Silybum marianum Widespread on District Roadsides, grasslands, disturbed openings

Scotch cottonthistle

Onopordum acanthium 4 0.60 4 0.60 Yes Roadside, rangeland, prairies, riparian

Totals 1,442 1,191.40 1,411 1,449.77 347.21 1,824.70 594 2,047.54 1,578 194.74 5,025 4,883.45 2,171.91

Biennial Thistles Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 45% 45% 25% 40% 40% 5% Grubbing and pulling can be effective in controlling existing plant, but will not be 

effective on seed bank. Would only be used on small infestations. 

Mechanical control NA 5% 5% 15% 10% 10% 15% Thistles can be controlled with mowing or weed whackers, but can adversely affect 

desirable intermingled species.

Aminopyralid 0.08 to 0.11 NA NA 45% NA NA 48% Preferred treatment method. Longer soil residual than clopyralid. 90 percent control 

if applied at the bud stage.

Clopyralid + 2,4-D 0.38 + 0.95 NA NA NA NA NA 10% Treatment for young plants (actively growing thru flowering).

Metsulfuron 

methyl 0.04 NA NA NA NA NA 10% Good choice at the rosette to bud stage. It is harder on some wet-meadow grass species than chlorsulfuron.

Glyphosate 1.00 NA NA 5% 20% 20% 5% Non-selective. Apply postemergence to plants in the rosette state in spring or before 

freeze-up in the fall.

Picloram + 2,4-D 0.25 + 0.95 NA NA NA NA <1% <1% Appropriate from rosette to flowering, where there is an established seed bank at 

site, where soils are not sandy or gravelly, where treatments are within labeled 
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105

Biennial Thistles Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

distances from water or wells, and where adverse effects to desirable vegetation can 

be minimized.

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA 10% 3% Appropriate if treatment occurs at spring and fall rosette stage.

Chlorsulfuron + 

Clopyralid + 2,4-D

0.05 + 0.38

+ 0.95 NA NA NA NA NA 1%

Appropriate when there is an established seed bank at site. Treat from rosette to 

flowering. This treatment is particularly useful when Canada thistle occurs in the 

infestation mix. Combination to consider using when burn-down to prevent seed 

formation / set is needed or where resistance to sulfonylureas is a concern. It adds a 

second mode or site of action.

Chlorsulfuron + 

2,4-D 0.05 + 0.95 NA NA NA NA NA 1%

Combination to consider using when burn-down to prevent seed formation / set is 

needed or where resistance to sulfonylureas is a concern. It adds a second mode or 

site of action.

Chlorsulfuron 0.05 NA NA NA NA NA 1% Treatment at the rosette to bud stage. This treatment is particularly useful when 

Canada thistle occurs in the infestation mix.

Clopyralid 0.38 NA NA <1% NA NA <1% Post emergence in spring up to bud stage. Can also apply to fall re-growth. Results 

are best if applied to rapidly growing weeds. More selective than picloram.

Picloram + 2,4-D + 

Dicamba

0.25 + 0.95 

+ 0.50 NA NA NA NA 0% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Apply where residual control is desired.

Chlorsulfuron + 

Picloram 0.05 + 0.5 NA NA NA NA NA <1%

Use when there is an established seed bank at site, treat from rosette to flowering, 

where soils are not sandy or gravelly, where treatments are within labeled distances 

from water or wells, and where adverse effects to desirable vegetation can be 

minimized.

Targeted grazing 

(goats) NA NA NA NA 0% 0% 1% Goats will eat young plants.

No adequate 

control methods NA 50% 50% 15% 30% 20% 0% Large infestations may be infeasible to treat using manual/mechanical methods.

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on bull and milk thistle infestations. See Table B-1, Widespread Biological Control Agents on 

the Northwest Oregon District, for further information.
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

106

Table C-5. Borage: Locations and Treatment Key

Borage Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Common bugloss

Anchusa officinalis Currently unknown on District Fields, roadsides, riparian, waste areas

Gypsyflower/houndstounge

Cynoglossum officinale 1 0.10 1 0.10 No Roadsides, pastures, meadows, open forest

Patterson’s curse

Echium plantagineum Currently unknown on District Open areas, pastures

Borage Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 50% 50% 50% 50% Hand pulling is feasible for scattered plants or for areas where other control 

methods are not feasible. Manual control would be limited to small infestations. 

Glyphosate <3.00 NA NA 25% 25% 30% 15% Preferred herbicide near water.

Chlorsulfuron + 

2,4-D 0.06 + 0.95 NA NA NA NA NA 15%

Combination to consider using when burn-down to prevent seed formation / set is 

needed or where resistance to sulfonylureas is a concern. This combination adds a 

second mode or site of action.

Metsulfuron 

methyl + 2,4-D 0.04 + 0.95 NA NA NA NA NA 10%

Combination to consider using when burn-down to prevent seed formation / set is 

needed or where resistance to sulfonylureas is a concern. This combination adds a 

second mode or site of action. Less expensive than chlorsulfuron but is harder on 

some wet meadow grass species.

Metsulfuron 

methyl 0.04 to 0.08 NA NA NA NA NA 8% Can be used safely around grasses. Early post emergence, apply early spring to be most effective.

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA <1% 1% Appropriate from the seedling to flowering stage. Option to prevent resistance to 

sulfonylureas.

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% 1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirables can be minimized.

No adequate 

control methods NA 50% 50% 25% 25% 20% 0%
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

107

Table C-6. Buckwheat Family: Locations and Treatment Key

Buckwheat Family Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook 

Field Office

Marys Peak 

Field Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bohemian knotweed

Polygonum X bohemicum 2 0.13 2 0.13 No Riparian, waste areas, forest edges

Cultivated knotweed

Polygonum polystachyum 2 1.60 2 0.20 4 1.80 No Riparian, waste areas, forest edges

Curly dock

Rumex crispus 21 5.42 0.02 21 5.42 0.02 No Widespread in open disturbed areas

Giant knotweed

Polygonum sachanlinense 1 0.42 8 5.21 8 2 2.48 11 8.11 No Riparian, waste areas, forest edges

Japanese knotweed

Polygonum cuspidatum 10 1.66 86 11.05 1,313.81 1 0.10 0.10 2 0.54 2 20 34.95 119 48.30 1,313.91 No Riparian, waste areas, forest edges

Totals 10 1.66 110 17.03 1,313.83 3 1.70 0.10 10 5.76 24 37.62 157 63.76 1,313.93

Buckwheat Family Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 5% 5% <1% <1% <1% <1% Recommended when rhizomes can be completely removed. Should only be used for 

very small upland infestations (less than 50 stems).

Imazapyr 0.75 to 1.00 NA NA NA NA NA 50% Most effective treatment method. Repeat applications necessary.

Aminopyralid 0.11 NA NA 40% NA NA 30% Apply in mid-summer to autumn, when plants are fully leafed. Optimum results 

when plants are 3-5 ft. tall. Repeat applications necessary.

Glyphosate <3.00 NA NA 30% 10% 50% 15% Apply mid-summer to fall, when plants are fully leafed. Injection treatments are also 

effective. Repeat applications necessary.

Triclopyr 0.50 to 2.00 NA NA 30% NA NA 3% Apply midsummer to actively growing plants.

Triclopyr + 2,4-D 1.50 + 0.95 NA NA NA NA NA 2% Apply midsummer to actively growing plants.

No adequate 

control methods NA 95% 95% 0% 90% 50% 0%
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108

Table C-7. Buttercups: Locations and Treatment Key

Buttercups Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Creeping buttercup

Ranunculus repens 1 0.02 1.20 10 1.30 5.00 1 0.00 100.00 12 1.32 106.20 In areas1 Roadside, fields, pastures, forest edges, riparian

Lesser celandine

Ranunculus ficaria Currently unknown on District Woodland, urban, wetland, riparian

1. In Siuslaw, Tillamook, and Cascades Field Offices

Buttercups Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field Office West Eugene 

Wetlands

Manual methods NA 60% 60% 2% 20% 20% 5% Roots must be removed from site, will regenerate from stem fragments and 

runners.

Aminopyralid 0.05 to 0.11 NA NA NA NA NA 25% Apply to actively growing plants.

Glyphosate <3.00 NA NA 40% 75% 60% 10% Effective when applied in summer/fall before leaf dieback.

Metsulfuron methyl 0.01 to 0.08 NA NA NA NA NA 20% Apply early when plants are small and actively growing.

Chlorsulfuron 0.05 NA NA NA NA NA 10% Treat marshes, swamps and bogs after water has receded as well as seasonally 

dry flood deltas. 

Dicamba + 2,4-D 0.50 to 1.00

+ 0.95 NA NA NA NA 5% 5% Apply early spring before flowers appear.

Triclopyr 2.00 NA NA 56% NA NA 15% Apply when actively growing to full bloom.

Triclopyr + 2 4-D 2.00 + 0.95 NA NA NA NA NA 5% Apply when actively growing to full bloom.

2,4-D 0.95 NA NA NA NA 5% 5% Apply in spring to rosettes.

Picloram 0.50 to 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and 

where soils are not sandy or gravelly, where treatments are within labeled 

distances from water or wells, and where adverse effects to desirables can be 

minimized. Evaluate soil, slope, and proximity to water when considering this 

herbicide.

Targeted grazing 

(sheep) NA NA NA NA NA <1% <1% Sheep will feed on seedlings and young vines at ground level. (Some buttercup species can be toxic.)

Mechanical control NA 2% 2% 2% <1% <1% 0% Tillage must be conducted before roots become well established.
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

109

Buttercups Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field Office West Eugene 

Wetlands

No adequate 

control methods NA 38% 38% 0% 5% 10% 0%

Table C-8. Canada Thistle: Locations and Treatment Key

Canada Thistle Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Canada thistle

Cirsium arvense 1,236 1,256.51 792 634.10 142.54 1,418.80 422 1,595.51 1,314 174.12 3,764 3,660.25 1,561.34 Yes Grasslands, open forest, roadside, pastures, clearings

Canada Thistle Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Clopyralid 0.50 NA NA 30% NA NA 35% One of the preferred herbicide treatments, post-frost.

Aminopyralid 0.08 to 0.11 NA NA 30% NA NA 30% One of the most effective herbicides. Apply post-emergence, bud stage to 

senescence. Applications can be made into winter if conditions permit.

Glyphosate (Minimal) NA NA 25% 35% 35% 24% Would be used where herbicide treatments could get into the water.

Chlorsulfuron 0.06 NA NA NA NA NA 5% Can be used for Canada thistle at any stage.

Clopyralid + 2,4-D 0.50 + 0.95 NA NA NA NA NA 1% Treatment for young plants (actively growing thru flowering). Adding 2,4-D is helpful 

if treatment occurs at the bud to flowering stage.

Picloram + 2,4-D 0.25 + 0.95 NA NA NA NA <1% <1%

Appropriate at sites where there is a known seed bank, where soils are not sandy or 

gravelly, where treatments are within labeled distances from water or wells, and 

where adverse effects to desirable vegetation can be minimized. Adding 2,4-D is 

helpful if treatment occurs at the bud to flowering stage.

Picloram 0.25 NA NA NA NA NA <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

110

Canada Thistle Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Mechanical control NA 0% 0% 10% 10% 10% 5%

Mowing can be used to reduce the nutrient storage in the roots and suppress flower 

formation. However, for mowing to be effective it must be repeated at least every 3-

4 weeks for several seasons. Or should be combined with other control practices.

Manual NA 5% 5% 5% 5% 5% <1% Pulling is an inadequate control method; cutting and bagging heads can reduce seed 

set.

No adequate 

control methods NA 95% 95% 0% 50% 50% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on Canada thistle infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.

Table C-9. Carnations: Locations and Treatment Key

Carnations Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bladder campion

Silene vulgaris Currently unknown on District Open areas and meadows

Carnations Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 50% 50% 50% 50% Hand pull scattered plants or for areas where other control methods are not 

feasible. Limited to small infestations. 

Mechanical control NA 5% 5% 5% 5% 5% 5% Repeated mowing of small patches is laborious but effective.

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA NA 5% Apply in spring from rosettes to bolting, on plants with green basal leaves. 

Glyphosate <3.00 NA NA 32% NA NA 32% Apply in spring to actively growing plants from germination to bolting, with green 

basal leaves.
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Carnations Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Aminopyralid + 

Metsulfuron 

methyl

0.08 to 0.11

+ 0.12 to 

0.15

NA NA NA NA NA 3% Apply pre-emergence in fall or when target plants are in the seedling to rosette 

stage.

2,4-D 0.95 NA NA NA NA NA 5% Apply to spring rosettes or to bolting plants with green basal leaves.

No adequate 

control methods NA 45% 45% 13% 45% 45% 0%

Table C-10. Carrot Family: Locations and Treatment Key

Carrot Family Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Common fennel

Foeniculum vulgare Currently unknown on District Roadsides, ditches, open disturbed sites

Giant hogweed

Heracleum mantegazzianum 1 0.18 0.08 5 0.60 6 0.78 0.08 No Riparian, clearings, meadows, roadsides

Poison hemlock

Conium maculatum 20 1.23 25 1.83 No Roadside, meadow, riparian, flood plains, ditches

Totals 21 1.42 0.08 5 0.60 26 2.02 0.08

Carrot Family Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 5% 5% 5% 5% 5% 5% Good for single plants or small infestations, try to get as much of the taproot 

as possible to prevent regrowth.

Mechanical control NA 45% 45% 30% 45% 45% 5%

Target plants are suppressed with mowing or weed whackers before seed 

set, nonselectively removes growth of desirable species. May require 

multiple treatments per year for effective weed control.
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Carrot Family Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Aminopyralid + 

Metsulfuron methyl

0.08 to 0.11

+ 0.12 to 

0.15

NA NA NA NA NA 30% Pre-emergence in fall, or post-emergence in the seedling to rosette stage.

Metsulfuron methyl + 

Dicamba + 2,4-D

0.02 + 0.50

+ 1.00 NA NA NA NA NA 25% Appropriate for use in rights-of-way.

Imazapyr 0.50 NA NA NA NA NA 15% Non-selective. Apply pre-emergence or in the rosette stage. Can be used 

near water.

Chlorsulfuron + 2,4-D 0.05 + 0.95 NA NA NA NA NA 10%

Treat marshes, swamps and bogs after water has receded as well as 

seasonally dry flood deltas. (Do not make application to natural or man-made 

bodies of water such as lakes, reservoirs, ponds, streams and canals.)

Metsulfuron methyl 0.07 NA NA NA NA NA 5%

Treat marshes, swamps and bogs after water has receded as well as 

seasonally dry flood deltas. (Do not make application to natural or man-made 

bodies of water such as lakes, reservoirs, ponds, streams and canals.)

Glyphosate 1.00 to 2.00 NA NA 5% 5% 5% 5% Use where herbicide treatments could contact water. For glyphosate, apply 

to rosettes before they bolt.

No adequate control 

methods NA 50% 50% 60% 45% 45% 0%

Table C-11. Geranium: Locations and Treatment Key

Geranium Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette Field 

Office

Siuslaw Field Office Tillamook Field Office Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Herb Robert

Geranium robertianum 169 224.59 241 139.51 10.93 113 28.07 159.00 520 172.91 20.00 537 95.87 1,580 660.94 189.93 Yes Roadside, forest

Shining geranium

Geranium lucidum 17 8.24 43 16.35 2.14 546 80.67 10.00 60 11.00 20.00 53 5.08 50.00 719 121.34 82.14 Yes Roadside, forest

Totals 186 232.83 284 155.86 13.07 659 108.74 169.00 580 183.91 40.00 590 100.95 50.00 2,299 782.28 272.07
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113

Geranium Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 5% 5% 5% 5% 5% 5% Pull, dig, or till before flowers and seeds.

Mechanical control NA 5% 5% 5% 5% 5% 5%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple treatments 

per year for effective weed control.

Propane torch NA NA NA 1% 0% 0% 1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).

Metsulfuron 

methyl 0.01 to 0.02 NA NA NA NA NA 20% Apply in spring before flowering on rapidly growing plants.

Aminopyralid 0.05 to 0.11 NA NA 20% NA NA 20% Apply in spring on rosette to flowering stages or in fall to seedlings or rosettes.

Imazapyr 0.38 to 0.75 NA NA NA NA NA 20% Apply pre- or post-emergence to control visible plants and seeds.

Dicamba + 

Diflufenzopyr 0.18 to 0.35 NA NA NA NA NA 15% Apply in spring to actively growing weeds. Use higher rates on perennials or large plants. 

Dicamba + 2,4-D 0.75 + 0.25 NA NA NA NA 5% 5% Apply in spring before flowering on rapidly growing plants.

2,4-D 0.95 NA NA NA NA 5% 5% Apply from seedling to flowering, to actively growing plants.

Glyphosate <3.00 NA NA 3% 50% 50% 3% Apply to rapidly growing plants. Use higher rates on larger plants. 

Triclopyr + 2 4-D 1.00 + 1.00 NA NA NA NA NA 1% Provides excellent control (>95%) according to Weed Control in Natural Areas in the 

Western United States (DiTomaso et al. 2013).

Imazapic 0.03 NA NA NA NA NA <1% Provides good control (80-95%) according to Weed Control in Natural Areas in the 

Western United States (DiTomaso et al. 2013).

Sulfometuron 

methyl 0.14 NA NA NA NA NA <1% Apply during the rainy season when weeds are rapidly growing, has mixed selectivityand desired grasses may be stunted.

Fluroxypyr 0.49 NA NA NA NA NA <1% Apply in spring on rapidly growing plants.

No adequate 

control methods NA 90% 90% 66% 40% 30% 0%
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114

Table C-12. Hawkweeds: Locations and Treatment Key

Hawkweeds Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette Field 

Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Orange hawkweed

Hieracium aurantiacum 3 0.21 3 0.21 No Roadside, open forest, pasture, rangeland

Yellow hawkweed

Hieracium floribundum Currently unknown on District Roadside, grasslands, forest

Hawkweeds Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 5% 5% 2% 5% 5% 5% Hand pulling effective for small infestations. 

Clopyralid 0.25 to 0.5 NA NA 45% NA NA 45% For meadow hawkweed, apply up to bloom stage. For orange hawkweed, apply in 

the spring before bolting. Preferred on orange hawkweed. 

Triclopyr + 

Clopyralid

0.40 to 0.60 + 

0.14 to 0.19 NA NA 30% NA NA 30% Preferred for meadow hawkweed; apply rosette to early bolt. Triclopyr not necessary unless seed set is imminent.

Aminopyralid 0.08 NA NA 23% NA NA 20% Apply from seedling to full bloom in spring.

Dicamba + 2,4-D 0.5 + 0.95 NA NA NA NA <1% <1% Appropriate from the seedling to flowering stage.

Picloram 0.25 to 0.5 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Glyphosate 2.00 NA NA <1% 80% 80% <1% Non-selective.

No adequate 

control methods NA 95% 95% 0% 15% 15% 0%
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115

Table C-13. Knapweeds: Locations and Treatment Key

Knapweeds Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Diffuse knapweed

Centaurea diffusa 2 1.10 3 1.70 5 2.80 No Roadsides, waste areas

Malta thistle

Centaurea melitensis Currently unknown on District Disturbed soils, grassy areas

Meadow knapweed

Centaurea ×moncktonii 22 13.02 288 395.27 71.23 6 1.37 25.10 55 31.05 229 52.42 600 493.13 96.33 In areas1

Widespread on western portion of the district:

roadsides, fields, meadows, forest openings, waste areas

Spotted knapweed

Centaurea stoebe L. ssp.

micranthos

53 29.71 45 28.73 4.57 2.60 33 18.94 45 26.95 176 104.33 7.17 In 

areas2 Roadside, pasture, open forests, prairies, waste areas

Yellow starthistle

Centaurea solstitialis 3 0.20 3 0.20 No Grasslands, rangelands, roadside

Totals 77 43.83 333 424.00 75.8 6 1.37 27.7 88 49.99 280 81.27 784 600.46 103.5

1. In Siuslaw, Tillamook, and Marys Peak Field Offices.

2. In Tillamook and Marys Peak Field Offices.

Knapweeds Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 5% 50% 25% 17%

Hand pulling is feasible for scattered plants or for areas where other control 

methods are not feasible. Manual control would be limited to small infestations and 

would be needed up to 3 times a year. Sometimes an inadequate control method in 

hard compacted soils (roadsides).

Aminopyralid 0.05 to 0.11 NA NA 45% NA NA 48% One of the most effective herbicides for knapweeds. Apply post-emergence, bud 

stage to senescence. Applications can be made into winter if conditions permit.

Aminopyralid + 

Metsulfuron 

methyl 

0.08 to 0.11

+ 0.12 to 

0.15

NA NA NA NA NA 15% Apply to plants in spring.

Clopyralid 0.38 NA NA 10% NA NA 10% Apply at the rosette to bolting stage.
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Knapweeds Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Clopyralid + 2,4-D 0.38 + 0.95 NA NA NA NA NA 5%

Treat invasive plants from rosette to flowering. It also offers residual control for late 

season applications to kill fall rosettes and to inhibit seedling growth the following 

year.

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1% Apply post-emergence from rosette to beginning of bolting, or autumn rosette. 

Optimal at early flowering stage.

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Glyphosate (minimal) NA NA 40% 5% 30% 5% Appropriate where adverse effects to desirable vegetation can be minimized. Use 

where treatments could get into the water.

No adequate 

control methods NA 50% 50% 0% 45% 45% 0% Manual/mechanical not effective on older plants.

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on diffuse, meadow, and spotted knapweed and yellow starthistle infestations. See Table B1, Widespread Biological Control Agents on the Northwest Oregon District, for further information.

Table C-14. Lilies, Iris, Sedges, Rushes: Locations and Treatment Key

Lilies, Iris, Sedges, Rushes: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook 

Field Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Daffodil

Narcissus 1 0.00 1 0.00 No Roadsides, wet meadows, old homesites

Italian arum

Arum Italicum Currently unknown on District Urban areas, forests, roadsides, shady areas

Yellow flag iris / paleyellow iris

Iris pseudacorus 1 0.19 1 0.19 No Aquatic, wet shores of rivers, ditches, and in marshes

Totals 2 0.19 2 0.19 
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Lilies, Iris, Sedges, Rushes: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative (and Alternative 21)

(Alternative 21

and) Alternative 3

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 20% 20% 20% 19% 18% 15% Hand pulling can be effective on single plants.

Imazapyr 0.75 to 1.00 NA NA NA NA NA 50% Apply post-emergence to plants at pre-bloom stage or to late season plants in 

autumn.

Glyphosate <3.00 NA NA 79% 40% 40% 25% Apply post-emergence to foliage when plants are growing rapidly, but before 

flowering in late spring or early summer. Can also apply in fall.

2,4-D 1.00 NA NA NA NA 1% 5% Post-emergence to early bloom. Use aquatic formulations near water.

Mechanical 

control NA 1% 1% 1% 1% 1% 5% Tractor can be effective but difficult to get entire rhizome.

Hexazinone 0.75 NA NA NA NA NA <1% Apply pre-emergence or early post emergence. Primarily for road right-of-ways. 

Not registered for aquatic use; would not be used on yellow flag iris.

No adequate 

control methods NA 100% 100% 100% 100% 100% 0%

1. Yellow flag iris, an aquatic species, would only be treated under Alternative 3. If sites of non-aquatic species in this species group where treated, they could be treated under the No Action Alternative and Alternative 2.

Table C-15. Loosestrifes: Locations and Treatment Key

Loosestrifes Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Creeping jenny

Lysimachia nummularia 2 0.41 2 0.41 No Riparian, meadows, marshes, forests

Garden loosestrife

Lysimachia vulgaris Currently unknown on District Riparian along lakeshores, rivers, open wetland habitats

Purple loosestrife

Lythrum salicaria Currently unknown on District Riparian areas, ditches, wetlands, pond and lake margins
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118 

Loosestrifes Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate 

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office West Eugene 

Wetlands

Manual control NA 25% 25% 25% 25% 25% 25% Hand pulling or digging can be effective on single plants.

Triclopyr 1.00 NA NA 40% NA NA 40% Preferred treatment. Use aquatic formulations. It can be used at all stages but 

primarily at the flowering stage.

Glyphosate <3.00 NA NA 20% 60% 60% 15% Can be applied at all stages but primarily at the flowering stage. This is a nonselective product and care should be taken to avoid treating desirable vegetation.

Imazapyr 0.75 to 1.00 NA NA NA NA NA 15% Apply after mid-bloom until killing frost.

Metsulfuron 

methyl 0.04 to 0.08 NA NA NA NA NA 5% Most effective at flower-bud and flowering stage but can be applied earlier.

No adequate 

control methods NA 75% 75% 15% 15% 15% 0% 

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on purple loosestrife infestations. See Table B-1, Widespread Biological Control Agents on 

the Northwest Oregon District, for further information.

Table C-16. Miscellaneous Herbaceous - Annual: Locations and Treatment Key

Miscellaneous Herbaceous - Annual: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook 

Field Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Policeman's helmet

Impatiens glandulifera 2 0.50 11 2.51 13 3.01 No Riparian, woodland, wetland

Puncturevine

Tribulus terrestris Currently unknown on District Disturbed sites, roadsides, open disturbed areas, sandy soils
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119

Miscellaneous Herbaceous - Annual: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 20% 20% 10% 10% 10% 10% Hand pulling can be effective on single plants or small infestations.

Mechanical 

control NA 10% 10% 10% 10% 10% 10%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple 

treatments/year for effective weed control.

Imazapyr 0.75 NA NA NA NA NA 20% Non-selective and long soil residual activity. Use where adverse effects to desirable

vegetation can be minimized.

Glyphosate <3.00 NA NA 35% 50% 50% 20% Apply in spring to actively growing plants from germination to bolting, with green 

basal leaves.

Triclopyr 1.00 NA NA 35% NA NA 10% Apply at flowering. Can be used at all stages.

Glyphosate + 2,4-

D 0.50 + 0.70 NA NA NA NA 10% 8% Apply in late spring, prior to seed set.

Dicamba + 

Diflufenzopyr 0.18 to 0.35 NA NA NA NA NA 8% Apply in spring to actively growing weeds. Use higher rates on perennials or large plants. 

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA NA 7% Apply to actively growing plants. 

Aminopyralid 0.05 to 0.11 NA NA 10% NA NA 4% Apply to actively growing plants. 

Metsulfuron 

methyl 0.12 to 0.15 NA NA NA NA NA 3% Apply early when plants are small and rapidly growing.

2,4-D 1.00 NA NA NA NA 5% <1% Apply in spring to rosettes.

Picloram 0.50 to 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Evaluate soil, slope, and proximity to water when considering this herbicide. 

Targeted grazing 

(sheep) NA NA NA <1% <1% <1% <1% Sheep selectively choose broadleaved plants over grass. Fencing or herding required.

Propane torch NA <1% <1% <1% <1% <1% <1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).

No adequate 

control methods NA 70% 70% 0% 30% 15% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on puncturevine infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

120

Table C-17. Miscellaneous Herbaceous - Perennial: Locations and Treatment Key

Miscellaneous Herbaceous - Perennial: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bigleaf periwinkle

Vinca major 2 0.17 2 0.20 1 9.10 5 9.47 No Forest, roadside, old home sites, residential areas

Bittersweet / Climbing nightshade

Solanum dulcamara 4 1.00 11 5.00 1.76 10 2.70 25 8.70 1.76 In areas1

Roadsides, moist clearings, open 

forests

Brazilian verbena

Verbena bonariensis Currently unknown on District Wetlands, open areas

Common periwinkle

Vinca minor 1 0.29 0.29 29 6.77 30 7.06 0.29 No Forest, roadside

Field bindweed

Convolvulus arvensis 17 6.20 17 5.36 1.92 0.90 1 1.00 1 0.10 36 12.66 2.82 No Widespread along roadsides, residential and agricultural areas

Sulfur cinquefoil

Potentilla recta Currently unknown on District Roadsides, open areas, grasslands

Totals 21 7.20 31 10.83 3.97 2 0.20 0.90 1 1.00 41 18.67 96 37.89 4.87

1. In Siuslaw Field Office.

Miscellaneous Herbaceous - Perennial: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 40% 40% 10% 10% 10% 10% Hand pulling can be effective on single plants or small infestations.

Mechanical 

control NA 5% 5% 5% 5% 5% 5%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple 

treatments/year for effective weed control.

Imazapyr 0.75 to 1.00 NA NA NA NA NA 20% Non-selective and long soil residual activity. Use where adverse effects to desirable

vegetation can be minimized.

Glyphosate <3.00 NA NA 40% 60% 60% 20% Apply in spring to actively growing plants from germination to bolting, with green 

basal leaves.

Triclopyr 2.00 NA NA 20% NA NA 10% Apply at flowering. Can be used at all stages.

Glyphosate + 2,4-

D 0.50 + 0.70 NA NA NA NA 5% 5% Apply in late spring, prior to seed set.
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

121

Miscellaneous Herbaceous - Perennial: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Dicamba + 

Diflufenzopyr 0.18 to 0.35 NA NA NA NA NA 10% Apply in spring to actively growing weeds. Use higher rates on perennials or large plants. 

Dicamba + 2,4-D 0.50 to 1.00

+ 0.95 NA NA NA NA NA 5% Apply to actively growing plants. 

Aminopyralid 0.05 to 0.11 NA NA 24% NA NA 10% Apply to actively growing plants.

Metsulfuron 

methyl 0.01 to 0.08 NA NA NA NA NA 3% Apply early when plants are small and rapidly growing.

2,4-D 0.95 NA NA NA NA 1% 1% Apply in spring to rosettes.

Picloram 0.50 to 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Evaluate soil, slope, and proximity to water when considering this herbicide.

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Evaluate soil, slope, and proximity to water when considering this herbicide. 

Targeted grazing 

(sheep) NA NA NA <1% <1% <1% <1% Sheep selectively choose weeds over grass. Fencing or herding required.

Propane torch NA 1% 1% 1% 1% 1% 1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).

No adequate 

control methods NA 54% 54% 0% 24% 18% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on field bindweed infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

122

Table C-18. Mustards: Locations and Treatment Key

Mustards Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw 

Field Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades

Field Office

Northwest Oregon 

District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Creeping yellowcress

Rorippa sylvestris 92 15.40 0.10 1 0.10 93 15.50 0.10 No Disturbed wetlands, ditches, wet meadows, poorly drained areas

Cultivated radish

Raphanus sativus 1 0.10 1 0.10 No Waste areas, fields

Dyers woad

Isatis tinctoria Currently unknown on District River banks, roadsides, flood plains

Garlic mustard

Alliaria petiolate Currently unknown on District Forest, woodland, urban, riparian

Money plant

Lunaria annua Currently unknown on District Widespread in forests, woodlands, near residential and urban areas

Purpleanther field pepperweed

Lepidium heterophyllum 4 0.03 4 0.03 No Riparian, floodplains, marshes, meadows, roadsides

Totals 4 0.03 92 15.40 0.10 1 0.10 1 0.10 98 15.63 0.10

Mustards Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 20% 20% 20% 20% Can work on individuals or small populations. Remove as much of the root as 

possible.

Chlorsulfuron + 

2,4-D 0.06 + 0.95 NA NA NA NA NA 35%

Combination to consider using where resistance to sulfonylureas is a concern. It adds 

a second mode or site of action. Apply when weeds are germinating or actively 

growing.

Aminopyralid + 

Metsulfuron 

methyl 

0.02 + 0.01 NA NA NA NA NA 15% Optimum timing is when the plants are in the bloom stage. 

Glyphosate 3.00 NA NA 79% 40% 40% 25% Non-selective.

Chlorsulfuron 0.06 NA NA NA NA NA 1% Safe around grasses and most effective at flower bud or flowering stage.

Triclopyr 1.00 NA NA 1% NA NA 1% Apply postemergence in spring when plants are in rosette stage. 

Imazapic 0.06 to 0.09 NA NA NA NA NA 1% Apply postemergence fall or early spring.
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

123

Mustards Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Metsulfuron 

methyl + 2,4-D 0.07 + 0.95 NA NA NA NA NA 1% Combination to consider using where resistance to sulfonylureas is a concern. Aquatic 2,4-D would be used in riparian areas.

Mechanical control NA <1% <1% <1% <1% <1% 1% Mowing multiple times can reduce root reserves and seed production.

No adequate 

control methods NA 50% 50% 0% 40% 40% 0%

Table C-19. Perennial Grasses: Locations and Treatment Key

Perennial Grasses Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

NISIMS

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bulbous canarygrass

Phalaris aquatica 14 1.61 14 1.61 Roadsides, forests, grasslands

Common velvet grass

Holcus lanatus 61 374.25 3.37 61 374.25 3.37 In areas1 Meadows, woodlands

Creeping velvet grass

Holcus mollis 1.20 8 1.30 37 3.79 45 5.09 1.20 Meadows, woodlands

European beachgrass

Ammophila arenaria 6 20.17 6 20.17 Dunes

Jubata grass

Cortaderia jubata Currently unknown on District

Limited distribution, ditch 

banks, coastal habitats, 

forests, roadsides

Meadow foxtail

Alopecurus pratensis 20 56.09 0.09 20 56.09 0.09 Meadows, fields

Orchardgrass

Dactylis glomerata 16 0.73 16 0.73 In areas2 Roadsides, meadows

Red top, creeping 

bentgrass

Agrostis stolonifera

33 119.57 0.04 33 119.57 0.04 Riparian, wet meadows

Reed canarygrass

Phalaris arundinacea 102 60.91 335 125.87 19.68 0.20 3 0.17 20.00 156 23.56 15.00 596 210.52 54.88 In areas2

Roadside, ditches, marshes, 

wet meadows
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

124

Perennial Grasses Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

NISIMS

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Slender false brome

Brachypodium 

sylvaticum

1,054 1,154.83 465 417.44 54.22 63 75.02 10.00 1,009 482.75 10.00 1,163 289.92 20.00 3,754 2,419.96 94.22 Yes

Widespread; roadside, forest, 

woodland, riparian, shady 

areas

Sweet vernal grass

Anthoxanthum 

odoratum

54 350.29 2.15 54 350.29 2.15 In 

areas1 Meadows, pastures

Tall fescue

Schedonorus 

arundinaceus

1 1.70 57 92.74 1.55 58 94.44 1.55 In 

areas1

Damp grasslands, river banks, 

coastal habitats

Tall oatgrass

Arrhenatherum elatius 27 22.70 0.35 27 22.70 0.35 Forest edges, meadows, fields

Timothy

Phleum pratense 2 0.10 2 0.10 Meadows, pastures, woodlands

Waxy mannagrass

Glyceria declinata Currently unknown on District Ditches, swales, seasonally wet habitats, disturbed areas

Weeping lovegrass

Eragrostis curvula Currently unknown on District Roadsides, disturbed areas, residential areas

Totals 1,157 1,217.44 1,090 1,581.57 81.45 63 75.02 11.40 1,020 484.22 30.00 1,356 317.27 35.00 4,686 3,675.53 157.85

1. In Siuslaw Field Office.

2. In Siuslaw, Marys Peak, and Cascades Field Offices.

Perennial Grasses Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Fluazifop-P-butyl 0.38 NA NA <1% NA NA <1% Research and Demonstration herbicide. Apply post-emergence. Spring is best to 

control seedlings, but established plants can be treated in mid-summer to fall.

Sethoxydim < 0.38 NA NA NA NA NA <1% Research and Demonstration herbicide. Apply post-emergence. Spring is best to 

control seedlings, but established plants can be treated in mid-summer to fall.

Manual control NA 25% 50% 10% 10% 0% 25% Remove entire plant. Effective for smaller populations of false brome.

Imazapyr 0.75 to 1.50 NA NA NA NA NA 10% Apply early spring when reed canarygrass is sprouting. 
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

125

Perennial Grasses Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Sulfometuron 

methyl 0.14 to 0.38 NA NA NA NA NA 5% Appropriate for use on roadsides.

Imazapyr + 

Glyphosate

0.75 to 1.50

+ 3.00 NA NA NA NA NA 25% Apply in spring to young growth.

Glyphosate <3.00 NA NA 40% 20% 20% 10% Non-selective. Good for pure stands. May require 2 to 3 years of retreatments.

Hexazinone 2.00 NA NA NA NA NA 5% Pre or postemergence. Mobile in soil and has long soil residual activity. Should not 

be used in areas with shallow water table. Ideal for upland use.

Mechanical 

control NA 25% <1% 10% 10% 10% 10% Mow to remove annual seed production, clean equipment prior to moving it elsewhere. Not effective treatment by itself.

No adequate 

control methods NA 50% 50% 38% 60% 70% 10%

Table C-20. Perennial Mints: Locations and Treatment Key

Perennial Mints Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Pennyroyal

Mentha pulegium 0.10 No Widespread, wetland, agricultural areas.

Yellow archangel

Lamiastrum galeobdolon 2 0.60 5 0.75 0.11 1 30.00 8 31.35 0.11 No Roadside, forest edges, riparian

Totals 2 0.60 5 0.75 0.21 1 30.00 8 31.35 0.11
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

126

Perennial Mints Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 25% 50% 10% 5% 5% 10%

Infestations can be suppressed by manual removal of plants before flowering, 

including rhizomes and stolons. Belowground tissues should be severed 

approximately three inches below soil surface.

Triclopyr 1.50 to 3.00 NA NA 45% NA NA 45% Apply when plants are mature. Most effective when they have bolted but before 

seed production.

Glyphosate + 

Triclopyr 2.00 + 2.00 NA NA 25% NA NA 25% Apply when actively growing and not during drought stress.

Glyphosate <3.00 NA NA 18% 90% 90% 10% Apply when plants are bolting but before seed production.

Metsulfuron 

methyl 0.10 NA NA NA NA NA 2% Effective on dry sites.

Mechanical 

control NA 0% 0% 2% 0% 0% 2%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple treatments 

per year for effective weed control.

2,4-D 1.00 NA NA NA NA 0% 5% Apply after bolting and before seed production. 

Propane torch NA NA NA 0% 0% 0% 1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).

No adequate 

control methods NA 75% 50% 0% 5% 5% 0%

Table C-21. Perennial Peas: Locations and Treatment Key

Perennial Peas Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Birdsfoot trefoil

Lotus corniculatus 5 0.64 0.11 5 0.64 0.11 No Roadsides, meadows, pastures, riparian

False indigo bush

Amorpha fruticosa Currently unknown on District Riparian along lakeshores, rivers, open wetland habitats

Flat pea

Lathyrus sylvestris 3.40 6 3.80 6 3.80 3.40 No Forest edges, meadows

Kudzu Currently unknown on District Forest, woodland, urban
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

127

Perennial Peas Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak 

Field Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Pueraria lobata

Perennial pea

Lathyrus latifolius 50 31.10 32 12.10 3.76 117 428.21 19 3.28 35 10.40 253 485.09 3.76 In areas1 Roadside, forest edges

Totals 50 31.10 37 12.74 3.87 117 428.21 3.40 25 7.08 35 10.40 264 489.53 7.27

1. In Siuslaw Field Office.

Perennial Peas Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 50% 50% 30% 50% 50% 30% Hand pulling can be used on small infestations or isolated plants, as long as 

belowground tissue is also removed (to prevent re-sprouting).

Aminopyralid 0.05 to 0.11 NA NA 30% NA NA 25% Apply in spring before flowering.

Clopyralid 0.23 to 0.49 NA NA 10% NA NA 10% Apply in spring before flowering.

Triclopyr 2.00 NA NA 15% NA NA 15% Apply in spring when plants are rapidly growing.

Glyphosate <3.00 NA NA 15% 25% 25% 10% Apply in spring before flowering.

Imazapyr 0.45 NA NA NA NA NA 4% Non-selective with long residual soil activity. Appropriate where adverse effects to 

desirable vegetation can be minimized.

2,4-D 0.95 NA NA NA NA 0% 1% Apply in spring to actively growing plants, particularly at bud to flower stage.

Picloram 0.50 to 0.95 NA NA NA NA 0% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Evaluate soil, slope, and proximity to water when considering this herbicide. 

Chlorsulfuron 0.05 NA NA NA NA 0% 1% Safe around grasses and most effective at flower bud or flowering stage.

Metsulfuron 

methyl 0.03 NA NA NA NA NA 1% Safe around grasses and most effective at flower bud or flowering stage.

Sulfometuron 

methyl 0.14 NA NA NA NA NA 1% Non-selective and can be used in limited areas (roadsides).

Propane torch NA NA NA <1% 0% 0% 1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

128

Perennial Peas Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Targeted grazing 

(goats or sheep) NA NA NA NA 0% 0% 1% Delay spring grazing until target plants are at least 8 inches tall.

Mechanical 

control NA <1% <1% <1% <1% <1% <1%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple treatments 

per year for effective weed control.

No adequate 

control methods NA 50% 50% 0% 25% 25% 0%

Table C-22. Snapdragons: Locations and Treatment Key

Snapdragons Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field Office

Marys Peak 

Field Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Butter and eggs

Linaria vulgaris 3 0.36 5 0.41 8 0.77 No Meadows, roadsides, waste places

Purple foxglove

Digitalis purpurea 844 848.00 987 1,453.30 326.30 15.80 13 17.74 200.00 1,844 2,319.04 542.10 In areas1 Roadside, open forests, clearings

Totals 847 848.36 987 1,453.30 326.30 15.80 13 17.74 5 0.41 200.00 1,852 2,319.82 542.10

1. In Cascades, Siuslaw, and Tillamook Field offices.

Snapdragons Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 15% 15% 15% 15% 15% 15% Effective in spring on small infestations.

Metsulfuron

methyl 0.12 to 0.15 NA NA NA NA NA 20% Apply in spring or fall to plants in the rosette stage or to bolting plants less than 12inches tall.

Chlorsulfuron +

2,4-D 0.05 + 0.70 NA NA NA NA NA 20% Apply in spring or fall to plants in the rosette stage or to bolting plants less than 12 inches tall.

Chlorsulfuron 0.05 NA NA NA NA NA 20% Apply in fall for most consistent control.
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Appendix C: Treatment Key, Invasive Plant Sites, and the Annual Treatment Plan

129

Snapdragons Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Imazapyr 0.75 to 1.50 NA NA NA NA NA 10% Apply in spring when plants are growing rapidly or apply in mid-fall to dormant 

infestation.

Picloram + 2,4-D 0.50 + 1.50 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Glyphosate <3.00 NA NA 75% 75% 75% 13% Apply in spring to rapidly growing plants.

Picloram 0.50 to 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized. 

Evaluate soil, slope, and proximity to water when considering this herbicide. 

Propane torch NA <1% <1% <1% <1% <1% 1% Most effective on small plants. Use only on infestations on non-flammable substrate 

(e.g., sand, gravel, concrete).

Mechanical 

control NA 1% 1% 1% 1% 1% 1%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple treatments 

per year for effective control.

No adequate 

control methods NA 84% 84% 9% 9% 9% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on butter and egg infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.

Table C-23. Spurges: Locations and Treatment Key

Spurges Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office

Siuslaw Field 

Office

Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Leafy spurge

Euphorbia esula 1 1.38 1 1.38 Roadsides, pastureland, waste areas

Oblong Spurge

Euphorbia oblongata Currently unknown on District Riparian
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130

Spurges Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Imazapyr 0.75 NA NA NA NA NA 40% Non-selective with no residual soil activity. Appropriate where an extensive seed 

bank is present.

Glyphosate (minimal) NA NA 60% 60% 60% 25% Non-selective with no residual soil activity. 

Mechanical 

control NA 15% 15% 15% 15% 15% 15% Mowing or weed whacking in conjunction with herbicide is effective control on infestations. 

Dicamba + 2,4-D 1.00 + 0.95 NA NA NA NA 9% 9% Apply in spring at flower emergence or to fall regrowth.

Imazapic 0.13 to 0.19 NA NA NA NA NA 5% Apply after summer dry period when plants begin to grow (fall / winter).

Glyphosate + 2,4-

D 0.50 + 1.50 NA NA NA NA 5% 5% Apply as spring treatment before seed set. May take 3-5 years of repeated application.

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Three to five consecutive years of treatment needed.

Picloram 0.50 to 1.00 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where 

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

Targeted grazing 

(goats) NA NA NA NA 1% 1% 1% Targeted grazing by goats/ sheep in spring can control spurges. Toxic to cattle and horses.

No adequate 

control methods NA 85% 85% 25% 24% 10% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on leafy spurge infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.

Table C-24. St. Johnswort: Locations and Treatment Key

St. Johnswort Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

St. Johnswort

Hypericum perforatum 674 2,506.89 968 2,026.07 411.92 1,863.70 544 2,093.15 200.00 2,186 6,626.10 2,475.62 Yes Roadside, fields, waste areas, disturbed openings
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131

St. Johnswort Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 20% 20% 20% 20% 20% 20% Only for very small infestations. Not effective control. 

Aminopyralid 0.08 to 0.11 NA NA 50% NA NA 35% Post-emergence to rapidly growing plants before bloom.

Glyphosate 2.00 NA NA 30% 70% 70% 30% Non-selective with no residual soil activity.

Metsulfuron 

methyl + 2,4-D 0.06 + 0.95 NA NA NA NA NA 1% Targets plants that are small or rapidly growing. 

Dicamba + 

Diflufenzopyr 0.35 NA NA NA NA NA 14% Primarily for use on roadsides.

Picloram + 2,4-D 0.50 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and where

soils are not sandy or gravelly, where treatments are within labeled distances from 

water or wells, and where adverse effects to desirable vegetation can be minimized.

No adequate 

control methods NA 80% 80% 0% 10% 10% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on St. Johnswort infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.

Table C-25. Sunflower Family: Locations and Treatment Key

Sunflower Family Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Bristly oxtongue

Picris echioides Currently unknown on District Roadsides, open areas, grasslands

Coltsfoot

Tussilago farfara Currently unknown on District

Riparian, forests, 

woodlands, riverbanks, 

shorelines, grasslands

Oxeye daisy

Leucanthemum 

vulgare

89 19.97 0.19 5.00 50.00 200.00 89 19.97 255.19 In 

areas1

Roadside, pastures, open 

woodlands, meadows

Stinking willie, 

tansy ragwort

Senecio 

jacobaea

1,221 1,509.32 1,296 1,510.77 242.16 1,981.40 772 2,199.09 2,459 508.81 5,748 5,727.99 2,223.56 Yes Widespread in roadsides, 

clearings
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132

Sunflower Family Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper Willamette 

Field Office Siuslaw Field Office Tillamook Field Office

Marys Peak Field 

Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Totals 1,221 1,509.32 1,385 1,530.74 242.35 1,986.40 772 2,199.09 50.00 2,459 508.81 200.00 5,837 5,747.96 2,478.75

1. In Siuslaw and Cascades Field Offices

Sunflower Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 30% 30% 10% 30% 30% 10%

Hand pulling and grubbing are effective on visible plants. These treatments 

stimulate the seed bank. Would only be used on small infestations and where 

retreatment is planned. 

Mechanical 

control NA 30% 30% 15% 40% 40% 15%

Target plants are suppressed with mowing or weed whackers before seed set, nonselectively removes growth of desirable species. May require multiple treatments 

per year for effective weed control.

Aminopyralid 0.05 to 0.11 NA NA 45% NA NA 45% Apply in spring at bud stage. Preferred treatment when desirable plants in 

susceptible families are not present. Longer soil residual than clopyralid. 

Clopyralid 0.23 to 0.49 NA NA 5% NA NA 5% Apply at the rosette to bolting stage.

Dicamba + 

Diflufenzopyr 0.18 to 0.35 NA NA NA NA NA 5% Apply in spring to actively growing weeds. Use higher rates on perennials or large plants. 

Metsulfuron 

methyl 0.02 to 0.04 NA NA NA NA NA 5% Use where resistance to sulfonylureas is a concern or to prevent seed formation or set. Primarily on roadsides.

Picloram + 2,4-D 0.25 + 0.95 NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and 

where soils are not sandy or gravelly, where treatments are within labeled 

distances from water or wells, and where adverse effects to desirable vegetation

can be minimized. Evaluate soil, slope, and proximity to water when considering 

this herbicide. 

Glyphosate <3.00 NA NA 25% 25% 25% 13% Apply in spring to rapidly growing plants before flowering.

Targeted grazing 

(sheep and goats) NA NA NA NA 0% 0% 1% Palatable, but does not control.

Propane torch NA NA NA <1% 0% 0% 1% Most effective on small plants. Use only on infestations on non-flammable 

substrate (e.g., sand, gravel, concrete).

No adequate 

control methods NA 40% 40% 0% 5% 5% 0%
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Sunflower Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on stinking willie infestations. See Table B-1, Widespread Biological Control Agents on the 

Northwest Oregon District, for further information.

Table C-26. Teasel: Locations and Treatment Key

Teasel Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette Field 

Office

Siuslaw Field Office Tillamook Field 

Office

Marys Peak Field 

Office

Cascades Field 

Office Northwest Oregon District

Common Habitat

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Fuller's teasel

Dipsacus fullonum 148 21.59 0.46 148 21.59 0.46 No Meadows, clearings, roadsides

Teasel Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook Field 

Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 30% 30% 10% 30% 30% 10% With small infestation, digging or hand pulling before flowering are effective 

controls. 

Aminopyralid 0.08 to 0.11 NA NA 40% NA NA 40% Provides over 90 percent control when applied to rosettes. Long soil residual 

activity.

Glyphosate <3.00 NA NA 20% NA NA 20% Apply to rapidly growing plants from rosette to early bolting stage.

Imazapic 0.13 to 0.19 NA NA 20% NA NA 10% Apply postemergence to rosettes.

Chlorsulfuron 0.05 NA NA NA NA NA 10% Apply post-emergence from rosette to bolting stage. 

Fluroxypyr 0.24 NA NA NA NA NA 2% Post-emergence from rosette to beginning of bolting, or fall rosette stage. Safe for 

most grasses.

Metsulfuron 

methyl 0.02 to 0.04 NA NA NA NA NA 2% Apply post-emergence from rosette to bolting stage.

Clopyralid 0.23 to 0.49 NA NA 10% NA NA 2% Treatments effective for young plants.

Dicamba + 

Diflufenzopyr 0.18 to 0.35 NA NA NA NA NA 2% Apply post emergence to rapidly growing plants.
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134

Teasel Group: Treatment Key (Methods and Considerations)

Treatment 

Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook Field 

Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Dicamba + 2,4-D 0.50 + 0.95 NA NA NA NA NA 2% Apply to rosettes until bolting stage.

No adequate 

control methods NA 70% 70% 0% 70% 70% 0%

Table C-27. Woody Species: Locations and Treatment Key

Woody Species Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field Office Marys Peak Field Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

NISIMS

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Butterfly bush

Buddleja davidii 4 0.32 4 0.32 No Riparian, roadside

Cherry laurel

Prunus 

laurocerasus

Currently unknown on District

Common gorse

Ulex europaeus 1 0.00 1 0.00 No

Forest, roadside, 

open disturbed 

sites

Common pear

Pyrus communis 6 63.89 0.27 6 63.89 0.27 No

Roadside, fields, 

meadows, 

woodlands

Cotoneaster spp.

Cotoneaster 1 0.02 1 0.02 No Open areas

Cutleaf 

blackberry

Rubus laciniatus

1,605 1,464.69 1,426 891.14 163.82 0.01 25.00 47 12.80 50.00 1,498 279.61 100.00 4,576 2,648.25 338.82 Yes

Open forest, 

roadside, wet 

areas

English holly

Ilex aquifolium 1 0.04 27 9.11 0.10 5.00 34 9.26 25.00 62 18.41 30.10 In areas1 Forests

English Ivy

Hedera helix 21 11.74 36 8.11 3 1.20 6.00 13 6.50 29 15.96 25.00 102 43.51 31.00 No

Forest, riparian, 

roadside, near 

residential areas, 

old home sites
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135

Woody Species Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field Office Marys Peak Field Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

NISIMS

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

European 

blackberry

Rubus vestitus

184 118.00 36 7.03 0.45 220 125.03 0.45 In 

areas1

Open forest, 

roadside

French broom

Genista 

monspessulana

4 6.80 1 0.04 0.10 1 0.10 6 6.94 0.10 No Forest, woodland,

meadows

Hawthorn

Crataegus 44 108.47 1.42 44 108.47 1.42 No

Meadows, 

woodlands, open 

areas

Himalayan 

blackberry

Rubus 

armeniacus

1,925 3,475.25 1,824 2,126.80 201.01 721 424.92 570.80 1,521 612.77 2,762 837.31 100.00 8,753 7,477.05 871.81 Yes

Widespread in 

open forest, 

roadside, wet 

areas.

Multiflora rose

Rosa multiflora 35 2.46 1.52 35 2.46 1.52 In areas1

Roadside, open 

areas

Non-native 

invasive roses

Rosa

63 95.95 0.03 63 95.95 0.03 No Open areas, 

prairies

Old man's beard

Clematis vitalba Currently unknown on District Woodland, urban, riparian

Oneseed 

hawthorn

Crataegus 

monogyna

14 12.62 0.43 14 12.62 0.43 No Forest edges, 

meadows

Scotch Broom

Cytisus scoparius 1,226 3,536.14 1,405 3,717.31 511.08 1,012 767.15 450.00 591 475.78 50.00 3,604 1,456.23 7,838 9,952.61 1,011.08 Yes

Open forest, 

roadside, 

woodland, 

grassland, 

clearings

Spanish broom

Spartium 

junceum

2 1.10 2 1.10 No Roadsides, open 

disturbed habitats
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136

Woody Species Group: Locations (Species and Sites)

Common Name

Scientific Name

Upper 

Willamette 

Field Office

Siuslaw Field Office Tillamook Field Office Marys Peak Field Office Cascades Field Office Northwest Oregon District

Common Habitat

NISIMS Sites

NISIMS

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

NISIMS Sites

Acres

Widespread?

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

NISIMS

Unmapped

Spurge laurel

Daphne laureola 0.10 0.10 No

Woodlands, shady 

areas, well 

drained soils

Striated broom

Cytisus striatus 2 0.16 1 0.10 3 0.26 No

Roadsides, forest 

openings, 

woodlands, 

meadows

Sweet cherry

Prunus avium 1 0.24 1 0.24 No Fields, hardwood forests

Tree of Heaven

Ailanthus 

altissima

Currently unknown on District

Forest, woodland, 

urban, riparian, 

residential areas

Totals 4,970 8,613.91 4,920 7,043.19 880.23 1,736 1,193.28 1,056.90 2,173 1,107.95 100.00 7,932 2,598.78 250.00 21,731 20,557.12 2,287.13

1. Marys Peak Field Office

Woody Species Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Manual control NA 5% 10% 5% 10% 9% 5% Grubbing can effectively control small infestations.

Mechanical control NA 45% 45% 53% 25% 35% 10% Cut shrubs off at ground level. Can be combined with herbicide treatments or 

multiple treatments over a period of years.

Triclopyr 2.00 NA NA 25% NA NA 50%

Used primarily as a cut stump treatment or drill and fill the stem of large mature 

plants. Use formulations labeled for aquatic use if treatments near water. Or Apply 

as a foliar treatment mid-summer to early fall to smaller plants.

Glyphosate <3.00 NA NA 15% 24% 40% 15% Apply as foliar or cut stump. Foliar treatments would be made in late summer. 

Aquatic formulations would be used near water. 

Imazapyr 1.00 to 1.50 NA NA NA NA NA 16% Apply late summer to early fall.

Triclopyr + 2 4-D 2.00 + 0.95 NA NA NA NA NA 1% Apply when plants are actively growing.
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Woody Species Group: Treatment Key (Methods and Considerations)

Treatment Method

Application 

Rate

(lbs./acre)

Percent of Acres where Treatment Would be Used

Treatment Considerations

No Action Alternative

Action 

Alternatives

Upper 

Willamette 

Field Office

Siuslaw Field Office Marys Peak / 

Tillamook 

Field Offices

Cascades

Field 

Office

West Eugene 

Wetlands

Triclopyr + 

Aminopyralid 1.00 + 0.11 NA NA 2% NA NA 2% Apply before bud to early flowering.

Targeted grazing 

(goats) NA NA NA NA 1% 1% 1% Effective at defoliating blackberries, but does not provide long-term control. Limited to areas without desirable plants or vehicle traffic.

Picloram NA NA NA NA <1% <1%

Appropriate from rosette to flowering stage, where there are seed banks and 

where soils are not sandy or gravelly, where treatments are within labeled 

distances from water or wells, and where adverse effects to desirable vegetation

can be minimized.

No adequate 

control methods NA 50% 45% 0% 40% 15% 0%

Within the Northwest Oregon District boundary, the ODA releases and tracks biological control agents on common gorse and Scotch and French broom infestations. See Table B-1, Widespread 

Biological Control Agents on the Northwest Oregon District, for further information.

Table C-28. Summary of Species Group Information and Treatment Adequacy

Species Groups

Annual grassesAnnual peasAquatic speciesBiennial thistlesBorageBuckwheat familyButtercupsCanada thistleCarnationsCarrot familyGeraniumHawkweedsKnapweedsLilies, Iris, Sedges, RushesLoosestrifesMisc. herbaceous - annualMisc. herbaceous - perennialMustardsPerennial GrassesPerennial mintsPerennial peasSnapdragonsSpurgesSt. JohnswortSunflower familyTeaselWoody species

Number of Species in Group 4 1 7 6 3 5 2 1 1 3 2 2 5 3 3 2 6 6 16 2 5 2 2 1 4 1 22

Number unknown on District 6 2 2 1 1 1 1 1 1 2 1 2 3 3 2 1 2 3

NISIMS sites 34 446 3 5,025 1 157 12 3,764 NA 26 2,299 3 784 2 2 13 96 98 4,686 8 264 1,852 1 2,186 5,837 148 21,731

NISIMS acres1 7 355 0 4,883 0 64 1 3,660 NA 2 782 0 600 0 0 3 38 16 3,676 31 490 2,320 1 6,626 5,748 22 20,557

Unmapped acres1 0 75 2,172 1,314 106 1,561 NA 0 272 104 5 0 158 0 7 542 2,476 2,479 0 2,287

Adequate Treatment Methods Available (Percent)2

No Action Alternative

Upper Willamette Field Office 55 75 0 50 50 5 62 5 55 50 10 5 50 0 25 30 46 50 50 25 50 16 15 20 60 30 50

Siuslaw Field Office 55 75 0 50 95 5 62 5 55 50 10 5 50 0 25 30 46 50 50 50 50 16 15 20 60 30 55

West Eugene Wetlands 87 100 0 85 75 100 100 100 87 40 34 100 100 0 85 100 100 100 62 100 100 91 75 100 100 100 100

Marys Peak / Tillamook Field Offices 65 75 0 70 75 10 95 50 55 55 60 85 55 0 85 70 76 60 40 95 75 91 76 90 95 30 60
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Species Groups

Annual grassesAnnual peasAquatic speciesBiennial thistlesBorageBuckwheat familyButtercupsCanada thistleCarnationsCarrot familyGeraniumHawkweedsKnapweedsLilies, Iris, Sedges, RushesLoosestrifesMisc. herbaceous - annualMisc. herbaceous - perennialMustardsPerennial GrassesPerennial mintsPerennial peasSnapdragonsSpurgesSt. JohnswortSunflower familyTeaselWoody species

Cascades Field Office 65 75 0 80 80 50 90 50 55 55 70 85 55 0 85 85 82 60 30 95 75 91 90 90 95 30 85

Alternative 2 100 100 0 100 100 100 100 100 100 100 100 100 100 0 100 100 100 100 90 100 100 100 100 100 100 100 100

Alternative 3 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 90 100 100 100 100 100 100 100 100

1. Acres are rounded to the nearest digit

2. Red cells indicate that treatment methods are less than or equal to 50 percent adequate; yellow cells are greater than 50 percent and less than 100 percent adequate and green cells are 100 percent adequate.

Table C-29. Summary of Treatment Options Available under One or More Alternatives, by Species Group

Species Group

Treatment Method1

Annual grassesAnnual peasAquatic speciesBiennial thistlesBorageBuckwheat familyButtercupsCanada thistleCarnationsCarrot familyGeraniumHawkweedsKnapweedsLilies, Iris, Sedges, RushesLoosestrifesMisc. herbaceous - annualMisc. herbaceous - perennialMustardsPerennial GrassesPerennial mintsPerennial peasSnapdragonsSpurgesSt. JohnswortSunflower familyTeaselWoody species

Herbicide Treatment Methods

2,4-D          

Aminopyralid             

Aminopyralid + Metsulfuron methyl    

Chlorsulfuron       

Chlorsulfuron + 2,4-D     

Chlorsulfuron + Clopyralid + 2,4-D 

Chlorsulfuron + Picloram 

Clopyralid        

Clopyralid + 2,4-D   

Dicamba + 2,4-D           

Dicamba + Diflufenzopyr      

Fluazifop-P-butyl  

Fluridone 

Fluroxypyr  
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Species Group

Treatment Method1

Annual grassesAnnual peasAquatic speciesBiennial thistlesBorageBuckwheat familyButtercupsCanada thistleCarnationsCarrot familyGeraniumHawkweedsKnapweedsLilies, Iris, Sedges, RushesLoosestrifesMisc. herbaceous - annualMisc. herbaceous - perennialMustardsPerennial GrassesPerennial mintsPerennial peasSnapdragonsSpurgesSt. JohnswortSunflower familyTeaselWoody species

Glyphosate                           

Glyphosate + 2,4-D   

Glyphosate + Triclopyr 

Hexazinone   

Imazapic     

Imazapyr             

Imazapyr + Glyphosate 

Metsulfuron methyl             

Metsulfuron methyl + 2,4-D   

Metsulfuron methyl + Dicamba + 2,4-D 

Picloram          

Picloram + 2,4-D          

Picloram + 2,4-D + Dicamba 

Rimsulfuron 

Sethoxydim  

Sulfometuron methyl    

Triclopyr           

Triclopyr + 2 4-D    

Triclopyr + Aminopyralid 

Triclopyr + Clopyralid 

Non-Herbicide Treatment Methods

Manual control                          

Mechanical control                    

Propane torch        

Targeted grazing (cattle) 

Targeted grazing (goats or sheep)   

Targeted grazing (goats)   

Targeted grazing (sheep)   

1. Seeding, planting, and prescribed fire may occur in any species group.
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Table C-30. Annual Treatment Plan

Project Area Target/Objective Treatment Method Treatment Acres

Cascades Field Office

Beeline Orange hawkweed Herbicide 1

Crabtree Knotweed Herbicide 1

Harlan's Plantation Scotch broom, blackberry Mechanical (brush cutting) 12

Harlan's Plantation Scotch broom, blackberry Herbicide 12

Marmot Canal Knapweed, blackberry Herbicide 2

Marmot Dam Meadow knapweed, blackberry, Scotch broom, perennial peavine, garlic mustard,

teasel, poison hemlock Herbicide 11

Mensinger Bench Scotch broom, blackberry Mechanical (brush cutting) 14

Middle Gorge Knotweed Herbicide 3

Middle Gorge Road Blackberry, Scotch broom Herbicide 3

Mill City Parcel Yellow archangel, false brome, blackberry, ivy, vinca Herbicide 3

Miller Quarry Diffuse knapweed, Scotch broom Herbicide 9

Molalla Corridor Sites Blackberry, Scotch broom, knapweed Herbicide 10

Mt Hood Quarry False brome, Scotch broom Herbicide 2

Pinecrest Knapweed Herbicide 1

Rogers Mtn Ivy, blackberry Herbicide 1

Sandy River Basin - Little Sandy 2 Inventory and treat EDRR species as needed Would vary depending on 

species found

4571

(limited BLM)

Sandy River Basin - Little Sandy Dam area Inventory and treat EDRR species as needed Manual 31

Sandy River Basin - Marmot Dam EDRR and treat invasive plants species as needed Manual 101

Sandy River Basin - Middle Gorge Area Giant knotweed & EDRR Herbicide 1,8901

(limited BLM)

Sandy River Basin - Salmon River Lower BLM 

reach Inventory and treat EDRR species as needed Manual 7861(mostly BLM)

Sandy River Basin - Sandy BLM Channel to 

Wildcat Creek English ivy, policemen's helmet and EDRR Manual and herbicide 2011(limited BLM)

Sandy River Basin - Sandy Gorge English ivy & EDRR Herbicide 3,8921

(691 BLM)

Sandy River Basin - Sandy-Salmon 

Confluence Inventory and treat EDRR species as needed Manual 1951(mostly BLM)

Sandy River Basin - Wildcat 2 and Wildcat 3 Inventory and treat EDRR species as needed Would vary depending on 

species found

3671

(mostly BLM)

Silverfalls Knapweed, false brome, blackberry Herbicide 1

Sunday Morning Ivy Herbicide 1

Marys Peak Field Office

BLM Alsea maintenance yard Blackberry Herbicide 3

Eastline Pit Scotch broom, blackberries, geranium, false brome Herbicide 11
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Project Area Target/Objective Treatment Method Treatment Acres

Gunsite Pass Pit Bull thistle, tansy ragwort, Canada thistle Herbicide 12

Marys Peak Access Road & Hwy 34 Scotch broom, false brome, thin-leaved peavine, spotted and meadow knapweeds, shining 

geranium and herb Robert Herbicide

401

(partially Forest 

Service)

Pedee Creek Pit Scotch broom, geranium Herbicide 4

Quail Hollow Quarry Miscellaneous species for all pits including: false brome, knapweed, thistles and geranium Herbicide 9

Rock Pit and associated gravel road Scotch broom, false brome, thin-leaved peavine, spotted and meadow knapweeds, shining 

geranium and herb Robert Herbicide 5

Vernon Pit Miscellaneous species for all pits including: false brome, knapweed, thistles and geranium Manual 8

Whitehouse Pit Scotch broom, blackberries, geranium, false brome Mechanical and herbicide 12

Winney Pit Miscellaneous species for all pits including: false brome, knapweed, thistles and geranium Manual 4

Winney Road access Teasel, knotweed, blackberry Herbicide and mechanical 4

Yaquina Head Outstanding Natural Area Blackberry, teasel Manual 3

Yaquina Head Outstanding Natural Area Blackberry, teasel Mechanical 4

Siuslaw Field Office

Roadside infestations Knotweeds Herbicides 10

Roadside infestations Geranium Herbicides 15

Roadside infestations Knapweeds Manual and herbicides 120

Roadside infestations Perennial grasses (false brome) Manual and herbicides 118

Roadside infestations Woody species (English ivy, Scotch broom, blackberries, English holly, vinca, cherry laurel) Mechanical and herbicides 306

West Eugene Wetlands

Balboa Hawthorn/common pear/non-native rose Herbicide (cut stump) 0.25

Balboa Hawthorn/common pear/non-native rose Herbicide 5

Balboa Reed canarygrass Herbicide 0.5

Balboa Scotch broom Manual 0.1

Balboa Teasel Manual 0.1

Beaver Run Reed canarygrass Herbicide 0.1

Fir Butte Blackberry Herbicide 3

Fir Butte Tall oatgrass Herbicide 2

Fir Butte Meadow knapweed Herbicide 0.25

Greenhill Hawthorn/common pear/blackberry/non-native rose Herbicide 2

Greenhill Hawthorn/common pear/blackberry/non-native rose Herbicide (cut stump) 0.25

Greenhill Reed canarygrass Herbicide 0.25

Hansen Blackberry Herbicide 2.5

Hansen Meadow knapweed Herbicide 0.1

Isabelle Tall oatgrass Herbicide 0.05

Isabelle Scotch broom Manual 2

Long Tom Blackberry Herbicide 1
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Project Area Target/Objective Treatment Method Treatment Acres

Long Tom Non-native rose Herbicide 5

Long Tom Tall oatgrass Herbicide 0.25

North Taylor Blackberry Herbicide 0.05

North Taylor Shining geranium Herbicide 0.25

Oak Hill Scotch broom/blackberry Herbicide 3

Oak Hill Shining geranium Propane torch 0.3

Oak Hill Shining geranium Propane torch 0.3

Oxbow West Hawthorn/common pear Herbicide (cut stump) 1

Oxbow West Reed canarygrass Herbicide 1

Oxbow West Non-native rose/blackberry/hawthorn/common pear Herbicide 0.5

Oxbow West Scotch broom Manual 0.1

Oxbow West Teasel Manual 0.1

Rosy Blackberry/Scotch broom Herbicide 1

Rosy Reed canarygrass Herbicide 0.25

Rosy Scotch broom Manual 0.1

Rosy Teasel Manual 0.1

Speedway Hawthorn/common pear/blackberry Herbicide (cut stump) 2

Speedway Reed canarygrass Herbicide 1

Speedway Scotch broom Manual 2

Speedway Teasel Manual 2

Stewart Pond False brome Herbicide 0.1

Turtle Swale Hawthorn/common pear/blackberry Herbicide 0.5

Turtle Swale Reed canarygrass Herbicide 0.1

Turtle Swale Scotch broom Manual 1

Turtle Swale Teasel Manual 0.5

Vinci Hawthorn/common pear/blackberry Herbicide (cut stump) 0.5

Vinci Reed canarygrass Herbicide 0.1

Vinci Scotch broom Manual 1

Willow Corner Annex Hawthorn/common pear/blackberry Herbicide 0.1

Willow Corner Annex Hawthorn/common pear/blackberry Herbicide (cut stump) 0.1

Willow Corner Annex Reed canarygrass Herbicide 0.1

Willow Corner Annex Shining geranium Herbicide 0.1

Willow Corner Annex Shining geranium Manual 0.1

Tillamook

Dixie Mountain Potential focus areas Woody - Scotch broom, English ivy Manual 5

Little North Fork Wilson River Knotweed Herbicide 2

Nestucca roadsides Woody species, geranium Manual and herbicide 100
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Project Area Target/Objective Treatment Method Treatment Acres

Pacific City 80 Woody - Scotch broom Mechanical 15

Quarries and mineral sites Any invasive species Manual and herbicide 15

Yamhill County roadsides Perennial grass (false brome) Herbicide 10

Upper Willamette 

Roadside infestations Perennial grasses (false brome) Manual and herbicide 70

Roadside infestations Woody - Scotch broom/blackberry Manual, mechanical and 

herbicide 141

Many sites across the field office Geranium Manual and herbicide 25

Many sites across the field office Perennial mint (yellow archangel) Manual and herbicide 1

Many sites across the field office Knapweeds Manual and herbicide 50

East Fork Dee Creek - McKenzie River Knotweed Herbicide 2

1. Partnership done across various landownerships by various partners.
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Appendix D: Protection Measures

Standard Operating Procedures, Mitigation Measures, Conservation Measures, and Project Design Criteria

presented in this appendix are a compilation of information originally presented in:

• the 2007 Vegetation Treatments Using Herbicides on BLM Lands in 17 Western States PEIS (USDI 2007a), 

Record of Decision (USDI 2007b), and Biological Assessment (USDI 2007c);

• the Vegetation Treatments on BLM Lands in 17 Western States Programmatic Environmental Report (USDI 

2007d);

• the 2010 Vegetation Treatments on BLM Lands in Oregon FEIS (USDI 2010a) and Record of Decision (USDI 

2010b);

• the 2016 Vegetation Treatments Using Aminopyralid, Fluroxypyr, and Rimsulfuron PEIS (USDI 2016a), 

Record of Decision (USDI 2016b), and Biological Assessment (USDI 2016c);

• the 2013 National Marine Fisheries Service’s Aquatic Restoration Biological Opinion II (ARBO II, NMFS 

2013); and,

• the 2013 U.S. Fish and Wildlife Service’s Aquatic Restoration Biological Opinion II (ARBO II, USDI 2013a)

In addition, the BLM is in the process of consultation with the U.S. Fish and Wildlife Service and the National 

Marine Fisheries Service. Additional Project Design Criteria that are expected to be adopted through this 

consultation process.

Project Design Features

The following Project Design Features are adopted for this analysis to reduce effects of the action alternatives

(unless otherwise noted, Project Design Features are applicable to both Alternatives 2 and 3):

Special Status Species

Multiple issue sections (Issue 2 in Chapter 3 and Issues 4 to 10 in Appendix G) include effects to Special Status14

species. Bureau Sensitive species are those for which population viability is a concern, as evidenced by significant 

current or predicted downward trends in population numbers or density and habitat capability that would reduce 

a species’ existing distribution. Management of Bureau Sensitive species “must not result in a loss of species 

viability or create significant trends toward Federal listing” (USDI 2008b). Consultation with the U.S. Fish and 

Wildlife Service or the National Marine Fisheries Service has occurred for listed species on the District, including at 

the National level with the 2007 and 2016 PEISs. This consultation resulted in Conservation Measures applicable to 

listed species or species proposed for listing (see Protection Measures for Federally Listed Species later in this 

appendix). Mitigation Measures adopted with the Records of Decision for the 2007 and 2016 PEISs at the National 

level state that, “To protect Special Status wildlife species, implement Conservation Measures for terrestrial 

animals presented in the 2007 Vegetation Treatments on Bureau of Land Management Lands in 17 Western States 

and 2016 Vegetation Treatments Using Aminopyralid, Fluroxypyr, and Rimsulfuron Biological Assessments.” These 

Conservation Measures include herbicide-free buffers from non-target species. The following Project Design 

Features included in the analysis of Alternative 2 and Alternative 3, would further minimize the potential for 

invasive plant treatments to adversely affect a site or population of Bureau Sensitive species. The loss of a few 

individuals may be acceptable if treatments were expected to improve habitat conditions, which would provide 

long-term benefits to the population.

 14 Special Status species include species that are federally listed as threatened or endangered or proposed for listing, as well as 

Bureau Sensitive species (species that are rare, but are not federally listed or proposed for listing)
   

                                                                

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Appendix D – Protection Measures 

 Follow the Bureau Sensitive Species Treatment Conditions flowchart (Figure D‐1) when working in 

potential habitat for Bureau Sensitive species. 

Figure D‐1. Bureau Sensitive Species Treatment Conditions

 For treatments within the same watershed as a federally listed plant, animal, or resident fish or within 

1,500 feet of listed anadromous fish habitat, follow all Project Design Criteria outlined in ARBO II15. 

 On BLM‐administered lands in the West Eugene Wetlands, follow all Project Design Criteria outlined in the 

Biological Opinion For The Resource Management Plan For The West Eugene Wetlands In Lane County,

Oregon (USDI 2014b). 

Native Vegetation   For federally threatened or endangered upland plant species, follow all Project Design Criteria adopted in 

consultation with U.S. Fish and Wildlife Service. 

Additional Monitoring Under the Action Alternatives 

 As described in Figure D‐1, if a selective treatment method could have an effect on a Special Status plant, 

the BLM would monitor the response. Monitoring would happen yearly for a minimum of two years 

following the treatment, and would measure Special Status plant numbers, plant size, and whether plants 

are reproductive or not. If adverse effects occur (e.g., impacts or loss of a few individual Special Status  

15 Note that ARBO II does not address the use of rimsulfuron, fluazifop‐P‐butyl, fluroxypyr, or hexazinone and hence these 

herbicides cannot be used in these areas unless they are addressed through other consultation.

145 
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plants), the BLM would weigh the consequences of these effects against the potential long-term impacts 

of invasive plants that would be expected in the absence of treatments. It is expected that information 

gained from this monitoring will provide additional information to consider as part of Appendix C, 

Treatment Key; helping to refine future prescriptions for greater success.

Wildlife

• In federally listed, terrestrial wildlife species’ habitat, follow all Project Design Criteria developed in 

coordination with U.S. Fish and Wildlife Service.

• Apply Conservation Measures applicable to butterflies and moths, as appropriate, for other Bureau 

Sensitive terrestrial invertebrates.

Alternative 3 Project Design Features • Survey for western pond turtles and painted turtles before applying bottom barriers / weed mats or diverassisted suction harvest/tractors in the habitat of these species16 (e.g., ponds and streams/rivers with 

pools and/or coves). If either species is present, restrict these types of treatments to only occur between 

May 7 and July 15 or between August 15 and September 15.

Fish / Riparian 

• Apply the aquatic no-herbicide application buffers specified in the Aquatic Restoration Biological Opinion 

II (NMFS 2013) from the National Marine Fisheries Service to all waterbodies with known or suitable 

habitat for Bureau Sensitive fish and other Bureau Sensitive aquatic species. 

• Outside of BLM administered land at the West Eugene Wetlands, confine the use of fluazifop-P-butyl to 

flat, dry ground located greater than 300 feet from any surface water connected to a stream network to 

prevent herbicide mobilization.

Alternative 3 Project Design Features • In waterbodies that contain federally threatened or endangered fish species or provide critical habitat, 

follow all Project Design Criteria developed in coordination with NMFS.

• Delay aquatic herbicide treatments in side channels and connected backwaters until they are 

disconnected from the mainstem river or during the period of lowest flow.

• When using aquatic 2,4-D, glyphosate, imazapyr, or triclopyr in closed aquatic systems, implement a 

phased treatment (treating less than 50 percent of the surface area of the pond at a time) to reduce the 

likelihood of all of the aquatic plants dying at the same time, which would result in a rapid depletion of 

dissolved oxygen.

Traditional and Cultural Uses (Native American Interests) • At least one month prior to beginning treatments for the season, Annual Treatment Plans would be 

presented to potentially affected Tribes showing planned treatments and treatment areas. If these Tribes 

request coordination or consultation regarding proposed treatments, the BLM would seek to avoid 

conflict with tribal resource use by modifying the timing of treatments or posting signs to allow Tribal 

members to avoid treated areas. These proposed modifications would be determined in coordination 

with the Tribe and are not limited to those stated above. Additionally, modification to Annual Treatment 

Plans may be requested in order to avoid adverse affects to cultural features. Ultimately, a line officer will 

 16 This can be identified during the interdisciplinary team review of the Annual Treatment Plan.
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make an informed decision regarding the level of modification appropriate through tribal coordination or 

consultation. 

Soil• For slopes greater than 20 percent, use low ground- pressure equipment such as rubber-tired or rubber 

tracked equipment, use a slash [vegetation] mat under equipment, or limit heavy equipment to one pass.

Standard Operating Procedures and Mitigation 

Measures

In the following section, Standard Operating Procedures applicable to non-herbicide treatments are listed first 

under each resource, followed by the Standard Operating Procedures, Mitigation Measures, and Oregon FEIS 

Mitigation Measures applicable to herbicide applications.

Standard Operating Procedures have been identified to reduce adverse effects to environmental and human 

resources from vegetation treatment activities based on guidance in BLM manuals and handbooks, regulations, 

and standard BLM and industry practices. The list is not all encompassing, but is designed to give an overview of 

practices that would be considered when designing and implementing a vegetation treatment project on public 

lands (USDI 2007b:2-29). Effects described in this EA are predicated on application of the Standard Operating 

Procedures or equivalent, unless an on-site determination is made that their application is unnecessary to achieve 

their intended purpose or protection. For example, the Standard Operating Procedure to “Provide alternative 

forage sites for livestock, if possible” would not need to be applied where livestock are not present. In addition, if 

the parent handbook or policy direction evolves, it is assumed that the new direction would continue to provide 

the appropriate environmental protections (USDI 2010b:33).

2007 PEIS Mitigation Measures (marked as MMs in the list below) were identified for all potential adverse effects 

identified for herbicide applications in the Vegetation Treatments Using Herbicides on Bureau of Land 

Management Lands in 17 Western States Programmatic Environmental Impact Statement (USDI 2007a), and 

adopted by its Record of Decision. In other words, no potentially significant adverse effect identified in the 17 

States analysis remained at the programmatic scale after the PEIS Mitigation Measures were adopted. Like the 

Standard Operating Procedures, application of the Mitigation Measures is assumed in the analysis in this EA

2016 PEIS Mitigation Measures (marked as 2016 MMs in the list below) were identified for all potential adverse 

effects identified for herbicide applications in the Vegetation Treatments Using Aminopyralid, Fluroxypyr, and 

Rimsulfuron PEIS (USDI 2016a), and adopted by its Record of Decision. In other words, no potentially significant 

adverse effect identified in the analysis remained at the programmatic scale after the PEIS Mitigation Measures 

were adopted. Like the Standard Operating Procedures, application of the Mitigation Measures is assumed in the 

analysis in this EA.

Oregon FEIS Mitigation Measures (marked as Oregon FEIS MMs in the list below) were identified and adopted for 

adverse effects identified in the Final Vegetation Treatments Using Herbicides on BLM Lands in Oregon 

Environmental Impact Statement (USDI 2010a). Application of these measures is also assumed in the analysis in 

this EA. Again, no potentially significant adverse effect was identified at the programmatic scale in the Oregon FEIS 

with the Standard Operating Procedures and Mitigation Measures assumed.

Additional guidance, direction, orders, and protection measures can be found in numerous other BLM or 

Department of the Interior handbooks, manual, and management plans. Exclusion from this appendix does not 

indicate that these additional measures are not also potentially applicable. BLM manuals and handbooks are 

available online.
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Since Standard Operating Procedures, Conservation Measures, and some Mitigation Measures are taken from 

national level documents, not all attributes are applicable to conditions on the District. For example, Alaska 

Natives would not be consulted with (see Social and Economic Values Standard Operating Procedures) and Alaskan 

crab and scallop habitat does not exist on the District (see Fish Conservation Measures). However, reference to 

herbicides analyzed in the 2007 or 2016 PEISs (i.e., bromacil, diquat, diuron, fluridone, or tebuthiuron) and 

application methods (i.e., aerial herbicide application) that are not proposed for use on the District have been 

removed, as appropriate, to avoid confusion with the alternatives proposed in this EA. For example, the reference 

to aerial application was removed from the following Standard Operating Procedure:

• Take precautions to minimize drift by not applying herbicides when winds exceed >10 mph (>6 mph for 

aerial applications) or a serious rainfall event is imminent.

In addition, Standard Operating Procedures and Mitigation Measures for wild horse and burro herds and livestock 

are not included in this appendix, as they are not present on the Northwest Oregon District.

Guidance Documents

In addition to resource-specific guidance (listed below, under various resource headings), Standard Operating 

Procedures are also taken from the following BLM handbooks or manuals: 

Fire Use

BLM handbook H-9211-1 (Fire Management Activity Planning Procedures) and manuals 1112 

(Safety), 9200 (Fire Program Management) and 9211 (Fire Planning)

Mechanical

BLM Handbook H-5000-1 (Public Domain Forest Management), and manuals 1112 (Safety) and 

9015 (Integrated Weed Management).

Manual

BLM Domain Forest Management, and manuals 1112 (Safety), and 9015 (Integrated Weed 

Management).

Biological

BLM manuals 1112 (Safety), 4100 (Grazing Administration), 9014 (Use of Biological Control 

Agents on Public Lands), and 9015 (Integrated Weed Management) and Handbook H-4400-1 

(Rangeland Health Standards).

Chemical

BLM Handbook H-9011-1 (Chemical Pest Control), and manuals 1112 (Safety), 9011 (Chemical 

Pest Control), 9015 (Integrated Weed Management), and 9220 (Integrated Pest Management).

General

Fire Use

• Prepare fire management plan.

• Use trained personnel with adequate equipment.

• Minimize frequent burning in arid environments.

• Avoid burning herbicide-treated vegetation for at least 6 months.

Mechanical

• Ensure that power cutting tools have approved spark arresters.

• Ensure that crews have proper fire-suppression tools during the fire season.

• Wash vehicles and equipment before leaving weed infested areas to avoid infecting weed-free 

areas.

• Keep equipment in good operating condition.
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Manual

• Ensure that crews have proper fire-suppression tools during fire season.

• Minimize soil disturbance, which may encourage new weeds to develop.

Biological

• Use only biological control agents that have been tested and approved to ensure they are host 

specific.

• If using domestic animals, select sites with weeds that are palatable and non-toxic to the animals.

• Manage the intensity and duration of containment by domestic animals to minimize 

overutilization of desirable plant species.

• Utilize domestic animals to contain the target species in the treatment areas prior to weed seed 

set. Or if seed set has occurred, do not move the domestic animals to uninfested areas for a 

period of 7 days.

Chemical

• Prepare an operational and spill contingency plan in advance of treatment.

• Conduct a pretreatment survey before applying herbicides.

• Select the herbicide that is least damaging to the environment while providing the desired 

results.

• Select herbicide products carefully to minimize additional impacts from degradates, adjuvants, 

other ingredients, and tank mixtures.

• Apply the least amount of herbicide needed to achieve the desired result.

• Follow herbicide product label for use and storage.

• Have licensed or certified applicators or State-licensed “trainees” apply herbicides, or they can 

be applied by BLM employees under the direct supervision of a BLM-certified applicator.

• Use only USEPA-approved herbicides and follow product label directions and “advisory” 

statements.

• Review, understand, and conform to the “Environmental Hazards” section on the herbicide 

product label. This section warns of known herbicide risks to the environment and provides 

practical ways to avoid harm to organisms or to the environment.

• Minimize the size of application area, when feasible.

• Comply with herbicide-free buffer zones to ensure that drift will not affect crops or nearby 

residents/landowners.

• Post treated areas and specify reentry or rest times, if appropriate.

• Notify adjacent landowners prior to treatment, if appropriate.

• Keep a copy of Material Safety Data Sheets (MSDSs) at work sites. MSDSs are available for review 

at http://www.cdms.net.

• Keep records of each application, including the active ingredient, formulation, application rate, 

date, time, and location.

• Avoid accidental direct spray and spill conditions to minimize risks to resources.

• Take precautions to minimize drift by not applying herbicides when winds exceed >10 mph or a 

serious rainfall event is imminent.

• Use drift control agents and low volatile formulations.

• Conduct pre-treatment surveys for sensitive habitat and Special Status species within or adjacent 

to proposed treatment areas.

• Consider site characteristics, environmental conditions, and application equipment in order to 

minimize damage to non-target vegetation.

• Use drift reduction agents, as appropriate, to reduce the drift hazard to non-target species.

• Turn off application equipment at the completion of spray runs and during turns to start another 

spray run.

• Refer to the herbicide product label when planning revegetation to ensure that subsequent 

vegetation would not be injured following application of the herbicide.

• Clean OHVs to remove plant material.
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The BLM has suspended the use of the adjuvant R-11.

Land Use

Fire Use

• Carefully plan fires in the WUI to avoid or minimize loss of structures and property.

• Notify nearby residents and landowners who could be affected by smoke intrusions or other fire 

effects.

Mechanical

• Collaborate on project development with nearby landowners and agencies.

Manual

• Collaborate on project development with nearby landowners and agencies.

Biological

• Notify nearby residents and landowners who could be affected by biological control agents.

Chemical

• Comply with herbicide-free buffer zones to ensure that drift will not affect crops or nearby 

residents and landowners.

• Post treated areas and specify reentry times, if appropriate.

Air Quality

Standard Operating Procedures for air quality are taken from BLM’s Air Resource Management Manual (7300).

Fire Use

• Have clear smoke management objectives.

• Evaluate weather conditions, including wind speed and atmospheric stability, to predict effects 

of burn and impacts from smoke.

• Burn when weather conditions favor rapid combustion and dispersion.

• Burn under favorable moisture conditions.

• Use backfires, when applicable.

• Burn small vegetation blocks, when appropriate.

• Manage smoke to prevent air quality violations and minimize impacts to smoke-sensitive areas.

• Coordinate with air pollution and fire control officials, and obtain all applicable smoke

management permits, to ensure that burn plans comply with federal, state, and local regulations.

Mechanical

• Maintain equipment in optimal working order.

• Conduct treatment activities during the wetter seasons.

• Use heavy equipment under adequate soil moisture conditions to minimize soil erosion.

• Minimize vehicle speeds on unpaved roads.

• Minimize dust impacts to the extent practicable.

Manual

• Maintain equipment in optimal working order.

• Conduct treatment activities during the wetter seasons.

• Minimize vehicle speeds on unpaved roads.

• Minimize dust impacts to the extent practicable.

Chemical

• Consider the effects of wind, humidity, temperature inversions, and heavy rainfall on herbicide 

effectiveness and risks.

• Apply herbicides in favorable weather conditions to minimize drift. For example, do not treat 

when winds exceed 10 mph or rainfall is imminent.
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• Use drift reduction agents, as appropriate, to reduce the drift hazard.

• Select proper application equipment (e.g., spray equipment that produces 200- to 800-micron 

diameter droplets [spray droplets of 100 microns and less are most prone to drift]).

• Select proper application methods (e.g., set maximum spray heights, use appropriate buffer 

distances between spray sites and non-target resources).

Soil Resources

Standard Operating Procedures for soil resources are taken from BLM’s Soil, Water, and Air Management Manual

(7000).

General

• Assess the susceptibility of the treatment site to soil damage and erosion prior to treatment.

Fire Use

• Prescribe broadcast and other burns that are consistent with soil management activities.

• Plan burns so as to minimize damage to soil resources.

• Conduct burns when moisture content of large fuels, surface organic matter, and soil is high to 

limit the amount of heat penetration into lower soil surfaces and protect surface organic matter.

• Time treatments to encourage rapid recovery of vegetation.

• Further facilitate revegetation by seeding or planting following treatment.

• When appropriate, reseed following burning to re- introduce species, or to convert a site to a less 

flammable plant association, rather than to specifically minimize erosion.

Mechanical

• Time treatments to avoid intense rainstorms.

• Time treatments to encourage rapid recovery of vegetation.

• Further facilitate revegetation by seeding or planting following treatment.

• Use equipment that minimizes soil disturbance and compaction.

• Minimize use of heavy equipment on slopes >20%.

• Conduct treatments when the ground is sufficiently dry to support heavy equipment.

• Implement erosion control measures in areas where heavy equipment use occurs.

• Conduct mechanical treatments along topographic contours to minimize runoff and erosion.

• When appropriate, leave plant debris on site to retain moisture, supply nutrients, and reduce 

erosion.

• Prevent oil and gas spills to minimize damage to soil.

Manual

• Time treatments to avoid intense rainstorms.

• Time treatments to encourage rapid recovery of vegetation.

• Further facilitate revegetation by seeding or planting following treatment.

• Minimize soil disturbance and compaction.

Biological

• Minimize use of domestic animals if removal of vegetation may cause significant soil erosion or 

impact biological soil crusts.

• Closely monitor timing and intensity of biological control with domestic animals.

• Avoid grazing on wet soil to minimize compaction and shearing.

Chemical

• Minimize treatments in areas where herbicide runoff is likely, such as steep slopes when heavy 

rainfall is expected.

• Minimize use of herbicides that have high soil mobility, particularly in areas where soil properties 

increase the potential for mobility.

• Do not apply granular herbicides on slopes of more than 15% where there is the possibility of 

runoff carrying the granules into non-target areas.
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Water Resources

Standard Operating Procedures for water resources are taken from BLM’s Water Quality Manual (7240).

Fire Use

• Prescribe burns that are consistent with water management objectives.

• Plan burns to minimize negative impacts to water resources.

• Minimize burning on hillslopes, or revegetate hillslopes shortly after burning.

• Maintain a vegetated buffer between treatment areas and water bodies.

Mechanical

• Minimize removal of desirable vegetation near residential and domestic water sources.

• Do not wash equipment or vehicles in water bodies.

• Maintain minimum 25 foot wide vegetated buffer near streams and wetlands.

Manual

• Maintain vegetated buffer near residential and domestic water sources.

• Minimize removal of desirable vegetation near residential and domestic water sources.

• Minimize removal of desirable vegetation near water bodies.

• Minimize use of domestic animals near residential or domestic water sources.

• Minimize use of domestic animals adjacent to water bodies if trampling or other activities are 

likely to cause soil erosion or impact water quality.

Chemical

• Consider climate, soil type, slope, and vegetation type when developing herbicide treatment 

programs.

• Select herbicide products to minimize impacts to water. This is especially important for 

application scenarios that involve risk from active ingredients in a particular herbicide, as 

predicted by Risk Assessments.

• Use local historical weather data to choose the month of treatment.

• Considering the phenology of target aquatic species, schedule treatments based on the condition 

of the water body and existing water quality conditions.

• Plan to treat between weather fronts (calms) and at appropriate time of day to avoid high winds 

that increase water movements, and to avoid potential stormwater runoff and water turbidity.

• Review hydrogeologic maps of proposed treatment areas. Note depths to groundwater and areas 

of shallow groundwater and areas of surface water and groundwater interaction. Minimize 

treating areas with high risk for groundwater contamination.

• Conduct mixing and loading operations in an area where an accidental spill would not 

contaminate an aquatic body.

• Do not rinse spray tanks in or near water bodies.

• Do not broadcast pellets where there is danger of contaminating water supplies.

• Minimize the potential effects to surface water quality and quantity by stabilizing terrestrial 

areas as quickly as possible following treatment.

• Establish appropriate (herbicide-specific) buffer zones for species/populations (Tables D-1 and D2). (MM)

• Areas with potential for groundwater for domestic or municipal use shall be evaluated through 

the appropriate, validated model(s) to estimate vulnerability to potential groundwater 

contamination, and appropriate Mitigation Measures shall be developed if such an area requires

the application of herbicides and cannot otherwise be treated with non-herbicide methods. 

(MM)

• Use appropriate herbicide-free buffer zones for herbicides not labeled for aquatic use based on 

Risk Assessment guidance, with minimum widths from water of 25 feet for vehicle, and 10 feet 

for hand spray applications.
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• Maintain buffers between treatment areas and water bodies. Buffer widths should be developed 

based on herbicide and site-specific conditions to minimize impacts to water bodies.

• To protect domestic water sources, no herbicide treatments should occur within 100 feet of a 

well or 200 feet of a spring or known diversion used as a domestic water source unless a written 

waiver is granted by the user or owner. (Oregon FEIS MM)

• Site-specific analyses for roadside treatments should specifically consider that drainage ditches 

and structures lead to streams and that normal buffer distances, herbicide selection, and 

treatment method selection may need to be changed accordingly, particularly where those 

ditches are connected to streams with Federally Listed or other Special Status species. (Oregon 

FEIS MM)

• Buffer intermittent stream channels when there is a prediction of rain (including thunderstorms) 

within 48 hours. (Oregon FEIS MM)

• Proposals to boom spray herbicides within 200 feet of streams that are within 1,000 feet 

upstream from a public water supply intake, or proposals to spot apply herbicides within 100 feet 

of streams that are within 500 feet upstream from a public water supply intake, will include 

coordination with the Oregon Department of Environmental Quality and the municipality to 

whom the intake belongs. (Oregon FEIS MM)

Wetlands and Riparian Areas

Fire Use

• Following treatment, reseed or replant with native vegetation if the native plant community

cannot recover and occupy the site sufficiently.

Mechanical

• Manage riparian areas to provide adequate shade, sediment control, bank stability, and 

recruitment of wood into stream channels.

• Following treatment, reseed or replant with native vegetation if the native plant community 

cannot recover and occupy the site sufficiently.

Manual

• Following treatment, reseed or replant with native vegetation if the native plant community 

cannot recover and occupy the site sufficiently.

Biological

• Manage animals to prevent overgrazing and minimize damage to wetlands.

• Following treatment, reseed or replant with native vegetation if the native plant community 

cannot recover and occupy the site sufficiently.

Chemical

• Use a selective herbicide and a wick or backpack sprayer.

• Use appropriate herbicide-free buffer zones for herbicides not labeled for aquatic use based on 

Risk Assessment guidance, with minimum widths from water of 25 feet for vehicle, and 10 feet 

for hand spray applications.

• See mitigation for Water Resources and Vegetation. (MM)

Vegetation

Standard Operating Procedures for vegetation are taken from Handbook H-4180-1 (Rangeland Health Standards

Handbook), and manuals 5000 (Forest Management) and 9015 (Integrated Weed Management).

General

• Use weed-free feed for horses and pack animals. Use weed-free straw and mulch for 

revegetation and other activities.
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Fire Use

• Keep fires as small as possible to meet the treatment objectives.

• Conduct low intensity burns to minimize adverse impacts to large vegetation.

• Limit area cleared for fire breaks and clearings to reduce potential for weed infestations.

• Where appropriate, use mechanical treatments to prepare forests for the reintroduction of fire.

• Use plant stock or seed from the same seed zone and from sites of similar elevation when 

conducting revegetation activities.

Mechanical

• Power wash vehicles and equipment to prevent the introduction and spread of weed and exotic 

species.

• Remove damaged trees and treat woody residue to limit subsequent mortality by bark beetles.

• Use plant stock or seed from the same seed zone and from sites of similar elevation when 

conducting revegetation activities.

• Identify and implement any temporary domestic livestock grazing and/or supplemental feeding 

restrictions needed to enhance desirable vegetation recovery following treatment.

Manual

• Remove damaged trees and treat woody residue to limit subsequent mortality by bark beetles.

• Use plant stock or seed from the same seed zone and from sites of similar elevation when 

conducting revegetation activities.

Biological

• Use domestic animals at the time they are most likely to damage invasive species.

• Manage animals to prevent overgrazing and minimize damage to sensitive areas.

• Identify and implement any temporary domestic livestock grazing and/or supplemental feeding 

restrictions needed to enhance desirable vegetation recovery following treatment.

• Consider adjustments in the existing grazing permit, including the application of state or regional 

grazing administration guidelines, needed to maintain desirable vegetation on the treatment 

site.

• Use plant stock or seed from the same seed zone and from sites of similar elevation when 

conducting revegetation activities.

Chemical

• Refer to the herbicide label when planning revegetation to ensure that subsequent vegetation 

would not be injured following application of the herbicide.

• Use native or sterile plants for revegetation and restoration projects to compete with invasive 

plants until desired vegetation establishes.

• Minimize the use of terrestrial herbicides (especially sulfometuron methyl) in watersheds with 

downgradient ponds and streams if potential impacts to aquatic plants are identified. (MM)

• When necessary to protect Special Status plant species, implement all Conservation Measures for 

plants presented in the 2007 Vegetation Treatments on Bureau of Land Management Lands in 17 

Western States and 2016 Vegetation Treatments Using Aminopyralid, Fluroxypyr, and 

Rimsulfuron Biological Assessments (see Conservation Measures later in this appendix). (MM, 

2016 MM)

• Establish appropriate (herbicide-specific) buffer zones (Tables D-1 and D-2) around downstream 

water bodies, habitats, and species/populations of interest. Consult the Risk Assessments 

prepared for the PEIS for more specific information on appropriate buffer distances under 

different soil, moisture, vegetation, and application scenarios. (MM)

• Use Table D-4 to establish herbicide-specific buffer zones around downstream water bodies, and 

associated habitats and non-target plant species/populations of interest for aminopyralid, 

fluroxypyr, and rimsulfuron. Consult the Risk Assessments for more specific information on 

appropriate buffer distances under different soil, moisture, vegetation, and application 

scenarios. (2016 MM)
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Pollinators

Chemical

• Complete vegetation treatments seasonally before pollinator foraging plants bloom.

• Time vegetation treatments to take place when foraging pollinators are least active both 

seasonally and daily.

• Design vegetation treatment projects so that nectar and pollen sources for important pollinators 

and resources are treated in patches rather than in one single treatment.

• Minimize herbicide application rates. Use typical rather than maximum rates where there are 

important pollinator resources.

• Maintain herbicide free buffer zones around patches of important pollinator nectar and pollen 

sources.

• Maintain herbicide free buffer zones around patches of important pollinator nesting habitat and 

hibernacula.

• Make special note of pollinators that have single host plant species, and minimize herbicide 

spraying on those plants and in their habitats.

Fish and Other Aquatic Species

Standard Operating Procedures for fish and other aquatic organisms are taken from BLM Manuals, including 

Manuals 6500 (Wildlife and Fisheries Management) and 6500 (Wildlife and Fisheries Management)

Fire Use

• Maintain vegetated buffers near fish-bearing streams to minimize soil erosion and soil runoff into 

streams.

• Minimize treatments near fish-bearing streams during periods when fish are in sensitive life 

stages (e.g., embryo).

Mechanical

• Minimize treatments adjacent to fish-bearing waters.

• Do not wash vehicles in streams or wetlands.

• Refuel and service equipment at least 100 feet from water bodies to reduce the chance for 

pollutants to enter water.

• Maintain adequate vegetated buffer between treatment area and water body to reduce the 

potential for sediments and other pollutants to enter the water body.

Manual

• Refuel and service equipment at least 100 feet from water bodies to reduce the chance for 

pollutants to enter water.

• Minimize removal of desirable vegetation near fish-bearing streams and wetlands.

Biological

• Limit access of domestic animals to streams and other water bodies to minimize sediments 

entering water and potential for damage to fish habitat.

Chemical

• Use appropriate buffer zones based on label and Risk Assessment guidance.

• Minimize treatments near fish-bearing water bodies during periods when fish are in life stages 

most sensitive to the herbicide(s) used, and use spot rather than broadcast treatments.

• Use appropriate application equipment/method near water bodies if the potential for off-site 

drift exists.

• For treatment of aquatic vegetation, 1) treat only that portion of the aquatic system necessary to 

meet vegetation management objectives, 2) use the appropriate application method to minimize 
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the potential for injury to desirable vegetation and aquatic organisms, and 3) follow water use 

restrictions presented on the herbicide label.

• Limit the use of terrestrial herbicides in watersheds with characteristics suitable for potential 

surface runoff that have fish-bearing streams during periods when fish are in life stages most 

sensitive to the herbicide(s) used. (MM)

• To protect Special Status fish and other aquatic organisms, implement all Conservation Measures 

for aquatic animals presented in the 2007 Vegetation Treatments on Bureau of Land 

Management Lands in 17 Western States and 2016 Vegetation Treatments Using Aminopyralid, 

Fluroxypyr, and Rimsulfuron Biological Assessments (see Conservation Measures later in this 

appendix). (MM, 2016 MM)

• Establish appropriate herbicide-specific buffer zones for water bodies, habitats, or fish or other 

aquatic species of interest (Table D-3 and recommendations in individual Ecological Risk 

Assessments). (MM)

• Consider the proximity of application areas to salmonid habitat and the possible effects of 

herbicides on riparian and aquatic vegetation. Maintain appropriate buffer zones around 

salmonid-bearing streams. (MM)

• At the local level, consider effects to Special Status fish and other aquatic organisms when 

designing treatment programs. (MM)

• Use of adjuvants with limited toxicity and low volumes is recommended for applications near 

aquatic habitats. (Oregon FEIS MM)

Wildlife Resources

Standard Operating Procedures for wildlife resources are taken from BLM Manuals, including Manuals 6500 

(Wildlife and Fisheries Management) and 6780 (Habitat Management Plans)

Fire Use

• Minimize treatments during nesting and other important periods for birds and other wildlife.

• Minimize treatments of important forage areas immediately prior to important use period(s), 

unless the burn is designed to stimulate forage growth.

Mechanical

• Minimize treatments during nesting and other important periods for birds and other wildlife.

• Retain wildlife trees and other unique habitat features where practical.

Manual

• Minimize treatments during nesting and other important periods for birds and other wildlife.

• Retain wildlife trees and other unique habitat features where practical.

Biological

• Minimize the use of livestock grazing as a vegetation control measure where and/or when it 

could impact nesting and/or other important periods for birds and other wildlife.

• Consider and minimize potential adverse impacts to wildlife habitat and minimize the use of 

livestock grazing as a vegetation control measure where it is likely to result in removal or physical 

damage to vegetation that provides a critical source of food or cover for wildlife.

Chemical

• Use herbicides of low toxicity to wildlife, where feasible.

• Use spot applications or low-boom broadcast operations where possible to limit the probability 

of contaminating non-target food and water sources, especially non-target vegetation over areas 

larger than the treatment area.

• Use timing restrictions (e.g., do not treat during critical wildlife breeding or staging periods) to 

minimize impacts to wildlife.

• To minimize risks to terrestrial wildlife, do not exceed the typical application rate for applications 

of dicamba, glyphosate, hexazinone or triclopyr, where feasible. (MM)
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• Minimize the size of application areas, where practical, when applying 2,4-D and Overdrive®17 to 

limit impacts to wildlife, particularly through contamination of food items. (MM)

• Where practical, limit glyphosate and hexazinone to spot applications in grazing land and wildlife 

habitat areas to avoid contamination of wildlife food items. (MM)

• Do not use the adjuvant R-11 (MM)

• To protect Special Status wildlife species, implement Conservation Measures for terrestrial 

animals presented in the 2007 Vegetation Treatments on Bureau of Land Management Lands in 

17 Western States and 2016 Vegetation Treatments Using Aminopyralid, Fluroxypyr, and 

Rimsulfuron Biological Assessments (see Conservation Measures later in this appendix). (MM, 

2016 MM)

• Impacts to wildlife from herbicide applications can be reduced by treating habitat during times 

when the animals are not present or are not breeding, migrating or confined to localized areas 

(such as crucial winter range). (Oregon FEIS MM)

• When treating native plants in areas where herbivores are likely to congregate, choose 

herbicides with lower risks due to ingestion. This Mitigation Measure is applicable if large areas 

of the herbivores’ feeding range would be treated, either because the treatment areas are large

or the feeding area for an individual animal is small. (Oregon FEIS MM)

• Where there is a potential for herbivore consumption of treated vegetation, apply dicamba, 

imazapyr, and metsulfuron methyl at the typical, rather than maximum, application rate to 

minimize risks. (Oregon FEIS MM)

• Where possible, design native vegetation treatment areas to mimic natural disturbance mosaics. 

Patchiness is usually beneficial to most wildlife, and patchiness is usually tolerated by species 

that prefer contiguous habitat. (Oregon FEIS MM)

• Use of adjuvants with limited toxicity and low volumes is recommended for applications near 

aquatic habitats. (Oregon FEIS MM)

• When conducting herbicide treatments in or near habitats used by Special Status and listed 

terrestrial arthropods, design treatments to avoid the use of fluroxypyr, where feasible. If pretreatment surveys determine the presence of listed terrestrial arthropods, do not use fluroxypyr 

to treat vegetation. (2016 MM)

Threatened and Endangered Species

Standard Operating Procedures for threatened and endangered species are taken from BLM Manual 6840 (Special 

Status Species) and Vegetation Treatments Using Herbicides on BLM Lands in 17 Western States Programmatic 

Biological Assessment.

Fire Use

• Survey for Special Status species of concern if project may impact federally- and state-listed 

species.

• Minimize direct impacts to species of concern, unless studies show that species will benefit from 

fire.

Mechanical

• Minimize use of ground- disturbing equipment near Special Status species of concern.

• Survey for species of concern if project could impact these species.

• Use temporary roads when long-term access is not required.

Manual

• Survey for Special Status species of concern if project could impact these species.

Biological

• Survey for Special Status species of concern if project could impact these species.

 17 Overdrive is a trade name for a formulation of diflufenzopyr + dicamba.
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Chemical

• Provide clearances for Special Status species before treating an area as required by Special Status 

Species Program policy. Consider effects to Special Status species when designing herbicide 

treatment programs.

• Use a selective herbicide and a wick or backpack sprayer to minimize risks to Special Status 

plants.

• Avoid treating vegetation during time-sensitive periods (e.g., nesting and migration, sensitive life 

stages) for Special Status species in area to be treated.

Cultural Resources

Standard Operating Procedures for cultural resources are taken from BLM handbook H-8120-1 (Guidelines for 

Conducting Tribal Consultation); BLM manual 8100 (The Foundations for Managing Cultural Resources); and, BLM 

manual 8120 (Tribal Consultation Under Cultural Resource Authorities)18

See also:

• The 2015 State Protocol between the Oregon-Washington State Director of the BLM and the Oregon State 

Historic Preservation Officer regarding the manner in which the Bureau of Land Management will meet its 

responsibilities under the National Historic Preservation Act; and,

• The 2012 National Programmatic Agreement among the BLM, the Advisory Council on Historic 

Preservation, and the National Conference of State Historic Preservation Officers.

General

• Follow standard procedures for compliance with Section 106 of the National Historic 

Preservation Act as implemented through the National Programmatic Agreement and state 

protocols or 36 CFR Part 800, including necessary consultations with the State Historic 

Preservation Officers and affected Tribes.

• Identify opportunities to meet tribal cultural use plant objectives for projects on public lands.

Fire Use

• Identify cultural resource types at risk from fire use and design inventories that are sufficient to 

locate these resources. Provide measures to minimize impacts.

Mechanical

• Identify cultural resource types at risk from mechanical treatments and design inventories that 

are sufficient to locate these resources. Provide measures to minimize impacts.

• Consult with Tribes to locate any areas of vegetation that are of significance to the Tribe and that 

might be affected, adversely or beneficially, by mechanical treatments.

Manual

• Identify cultural resource types at risk from manual treatments and design inventories that are 

sufficient to locate these resources. Provide measures to minimize impacts.

• Consult with Tribes to locate any areas of vegetation that are of significance to the Tribe and that 

might be affected, adversely or beneficially, by manual treatments.

Biological

• Consult with Tribes to locate any areas of vegetation that are of significance to the Tribe and that 

might be affected, adversely or beneficially, by biological treatments.

Chemical

• Consult with Tribes to locate any areas of vegetation that are of significance to the Tribe and that 

might be affected by herbicide treatments; work with Tribes to minimize impacts to these 

resources.

 18 This manual has been superseded by Handbook H-1780-1 (Improving and Sustaining BLM-Tribal Relations). Guidance from 

this new handbook does not change Standard Operating Procedures described in this section.
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• Follow guidance under Human Health and Safety in the PEIS in areas that may be visited by 

Native peoples after treatments.

• Do not exceed the typical application rate when applying 2,4-D, hexazinone and triclopyr in 

known traditional use areas. (MM)

Paleontological Resources

Standard Operating Procedures for paleontological resources are taken from BLM handbook H-8270-1 (General 

Procedural Guidance for Paleontological Resource Management) and BLM manual 8270 (Paleontological Resource 

Management).

General

• Follow BLM Handbook H-8270-1 to determine known Condition 1 and Condition 2 

paleontological areas, or collect information through inventory to establish Condition 1 and 

Condition 2 areas, determine resource types at risk from the proposed treatment, and develop 

appropriate measures to minimize or mitigate adverse impacts.

Fire Use

• Monitor significant paleontological and cultural resources for potential looting of materials 

where they have been exposed by fire.

Visual Resources

Standard Operating Procedures for visual resources are taken from BLM handbooks H-8410-1 (Visual Resource 

Inventory) and H-8431-1 (Visual Resource Contrast Rating), and Manual 8400 (Visual Resource Management).

General

• At areas such as visual overlooks, leave sufficient vegetation in place, where possible, to screen 

views of vegetation treatments.

• Design activities to repeat the form, line, color, and texture of the natural landscape character

Fire Use

• Minimize use of fire in sensitive watersheds to reduce the creation of large areas of browned 

vegetation.

• Consider the surrounding land use before assigning fire as a treatment method. Avoid use of fire 

near agricultural or densely populated areas, where feasible.

• Lessen visual effects in Class I and Class II visual resource areas19.

Mechanical

• Minimize dust drift, especially near recreational or other public use areas.

• Minimize loss of desirable vegetation near high public use areas.

• Minimize earthwork and locate away from prominent topographic features.

• Revegetate treated sites.

• Lessen visual effects in Class I and Class II visual resource areas.

Manual

• Minimize dust drift, especially near recreational or other public use areas.

• Minimize loss of desirable vegetation near high public use areas.

• Lessen visual effects in Class I and Class II visual resource areas.

Biological

• At areas such as visual overlooks, leave sufficient vegetation in place, where possible, to screen 

views of vegetation treatments.

• Lessen visual effects in Class I and Class II visual resource areas.

 19 These are referred to as visual resource management areas in the Northwestern and Coastal Oregon Resource Management 

Plan (USDI 2016d).
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Chemical

• Minimize the use of broadcast foliar applications in sensitive watersheds to avoid creating large 

areas of browned vegetation.

• Minimize off-site drift and mobility of herbicides (e.g., do not treat when winds exceed 10 mph; 

minimize treatment in areas where herbicide runoff is likely; establish appropriate buffer widths 

between treatment areas and residences) to contain visual changes to the intended treatment 

area.

• If the area is a Class I or II visual resource, ensure that the change to the characteristic landscape 

is low and does not attract attention (Class I), or if seen, does not attract the attention of the 

casual viewer (Class II).

• Lessen visual impacts by: 1) designing projects to blend in with topographic forms; 2) leaving 

some low growing trees or planting some low-growing tree seedlings adjacent to the treatment 

area to screen short-term effects; and 3) revegetating the site following treatment.

• When restoring treated areas, design activities to repeat the form, line, color, and texture of the 

natural landscape character conditions to meet established Visual Resource Management (VRM) 

objectives.

Wilderness and Other Special Areas

Standard Operating Procedures for Designated Wilderness, Wilderness Study Areas, Areas of Critical 

Environmental Concern, and Wild and Scenic Rivers are taken from BLM Manuals, including Manuals 6330 

(Management of Wilderness Study Areas (WSAs)), 6340 (Management of Designated Wilderness Areas), and 6400 

(Wild and Scenic Rivers).

General

• Encourage backcountry pack and saddle stock users to feed their livestock only weed-free feed 

for several days before entering a Wilderness Area, and to bring only weed-free hay and straw20

onto BLM lands.

• Encourage stock users to tie and / or hold stock in such a way as to minimize soil disturbance and 

loss of native vegetation.

• Revegetate disturbed sites with native species if there is no reasonable expectation of natural 

regeneration.

• Provide educational materials at trailheads and other Wilderness entry points to educate the 

public on the need to prevent the spread of weeds.

• Use the least intrusive methods possible to achieve objectives, and use non-motorized 

equipment in Wilderness and off existing routes in Wilderness Study Areas, and where possible 

in other areas.

• Address Wilderness and special areas in management plans.

• Control of weed infestations shall be carried out in a manner compatible with the intent of Wild 

and Scenic River management objectives.

Fire Use

• Minimize soil-disturbing activities during fire control or prescribed fire activities.

• Revegetate sites with native species if there is no reasonable expectation of natural 

regeneration.

• Maintain adequate buffers for Wild and Scenic Rivers.

Mechanical

• If mechanized equipment is required, use the minimum amount of equipment needed.

• Time the work for weekdays or off-season.

 20 By policy, weed-free hay and straw is required on all BLM-administered lands in Oregon and Washington (USDI 2017). 
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• Require shut down of work before evening if work is located near campsites.

• Revegetate sites with native species if there is no reasonable expectation of natural 

regeneration.

• Maintain adequate buffers for Wild and Scenic Rivers.

Manual

• Revegetate sites with native species if there is no reasonable expectation of natural 

regeneration.

• Maintain adequate buffers for Wild and Scenic Rivers.

Biological

• Maintain adequate buffers for Wild and Scenic Rivers.

Chemical

• Use the “minimum tool” to treat noxious weeds and other invasive plants, relying primarily on 

the use of ground based tools, including backpack pumps, hand sprayers, and pumps mounted 

on pack and saddle stock.

• Use herbicides only when they are the minimum treatment method necessary to control weeds 

that are spreading within the Wilderness or threaten lands outside the Wilderness.

• Give preference to herbicides that have the least impact on non-target species and the 

wilderness environment.

• Implement herbicide treatments during periods of low human use, where feasible. Mitigation 

Measures that may apply to Wilderness and other special area resources are associated with 

human and ecological health and recreation (see Mitigation Measures for Vegetation, Fish and 

Aquatic Organisms, Wildlife Resources, Recreation, and Human Health). (MM)

Recreation

Standard Operating Procedures for recreation are taken from BLM Handbook H-1601-1 (Land Use Planning 

Handbook).

General

• Notify the public of treatment methods, hazards, times, and nearby alternative recreation areas.

Fire Use

• Control public access to potential burn areas.

• Schedule treatments to avoid peak recreational use times, unless treatments must be timed 

during peak times to maximize effectiveness.

Mechanical

• Control public access until potential treatment hazards no longer exist.

• Schedule treatments to avoid peak recreational use times, unless treatments must be timed 

during peak times to maximize effectiveness.

Manual

• Control public access until potential treatment hazards no longer exist.

• Schedule treatments to avoid peak recreational use times, unless treatments must be timed 

during peak times to maximize effectiveness.

Biological

• Control public access in areas with control agents to ensure that agents are effective.

• Schedule treatments to avoid peak recreational use times, unless treatments must be timed 

during peak times to maximize effectiveness.

• Notify the public of treatment methods, hazards, times, and nearby alternative recreation areas.

Chemical

• Schedule treatments to avoid peak recreational use times, while taking into account the 

optimum management period for the targeted species.
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• Adhere to entry restrictions identified on the herbicide product label for public and worker 

access.

• Post signs noting exclusion areas and the duration of exclusion, if necessary.

• Mitigation Measures that may apply to recreational resources are associated with human and 

ecological health (see Mitigation Measures for Vegetation, Fish and Other Aquatic Species, 

Wildlife Resources, and Human Health and Safety). (MM)

Social and Economic Values

General

• Post treatment areas.

• Notify adjacent landowners, grazing permittees, the public, and emergency personnel of 

treatments.

• Control public access to treatment areas.

• Consult with Native American Tribes and Alaska Natives whose health and economies might be 

affected by the project.

• To the extent feasible, hire local contractors and purchase supplies locally.

Chemical

• Post treated areas and specify reentry or rest times, if appropriate.

• Notify the public of the project to improve coordination and avoid potential conflicts and safety 

concerns during implementation of the treatment.

• Control public access until potential treatment hazards no longer exist, per herbicide product 

label instructions.

• Observe restricted entry intervals specified by the herbicide product label.

• Notify local emergency personnel of proposed treatments.

• Use spot applications or low-boom broadcast applications where possible to limit the probability 

of contaminating non-target food and water sources.

• Consult with Native American Tribes to locate any areas of vegetation that are of significance to 

the Tribes and Native groups and that might be affected by herbicide treatments.

• To the degree possible within the law, hire local contractors and workers to assist with herbicide 

application projects and purchase materials and supplies for herbicide treatment projects 

(including the herbicides) through local suppliers.

• To minimize fears based on lack of information, provide public educational information on the 

need for vegetation treatments and the use of herbicides in an integrated vegetation 

management program for projects proposing local use of herbicides.

• For herbicides with label-specified re-entry intervals, post information at access points to 

recreation sites or other designated public use or product collection areas notifying the public of 

planned herbicide treatments in languages known to be used by persons likely to be using the 

area to be treated. Posting should include the date(s) of treatment, the herbicide to be used, the 

date or time the posting expires, and a name and phone number of who to call for more 

information. (Oregon FEIS MM)

• Consider the potential for treatments to affect communities from herbicide-contaminated 

resources originating from the BLM, such as subsistence resources or water used downstream for 

human or agricultural uses. (Oregon FEIS MM)

• Coordinate with and/or notify neighboring landowners who may want to treat, or are already 

treating, adjacent lands. (Oregon FEIS MM)

• To the extent permitted by normal contracting authority, ensure materials safety data sheets and 

other informational or precautionary materials are available in languages spoken by the work 

crews implementing treatments. This includes but is not limited to material such as Occupational 

Safety and Health Administration standards along with agency, industry and manufacturers’ 
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recommendations and Human Health and Safety Standard Operating Procedures and Mitigation 

Measures or equivalent. (Oregon FEIS MM)

Rights-of-way

General

• Coordinate vegetation management activities where joint or multiple use of a ROW exists.

• Notify other public land users within or adjacent to the ROW proposed for treatment.

Fire Use

• Manage burns under powerlines so as to avoid negative impacts to the powerline.

Mechanical

• Apply appropriate safety measures when operating equipment within utility ROW corridors.

• Minimize exposed soil areas during treatment.

• Keep operations within prescribed ROW.

Manual

• Always use appropriate safety equipment and operating procedures.

• Utilize methods for disposal of vegetation that prevent spreading or reinfestation of unwanted 

vegetation.

Chemical

• Use only herbicides that are approved for use in ROW areas.

Human Health and Safety

General

• Wear appropriate safety equipment and clothing, and use equipment that is properly 

maintained.

Fire Use

• Use some form of pretreatment, such as mechanical or manual treatment, in areas where fire 

cannot be safely introduced because of hazardous fuel buildup.

• Notify nearby residents who could be affected by smoke.

• Maintain adequate safety buffers between treatment area and residences/structures.

• Burn vegetation debris off ROWs to ensure that smoke does not provide a conductive path from 

the transmission line or electrical equipment to the ground.

Mechanical

• Cut all brush and tree stumps flat, where possible, to eliminate sharp points that could injure a 

worker or the public.

• Ensure that only qualified personnel cut trees near powerlines.

Manual

• Cut all brush and tree stumps flat, where possible, to eliminate sharp points that could injure a 

worker or the public.

Chemical

• Establish a buffer between treatment areas and human residences based on guidance given in 

the HHRA, with a minimum buffer of 100 feet for ground applications, unless a written waiver is 

granted.

• Use protective equipment as directed by the herbicide product label.

• Post treated areas with appropriate signs at common public access areas.

• Observe restricted entry intervals specified by the herbicide product label.

• Provide public notification in newspapers or other media where the potential exists for public 

exposure.
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• Store herbicides in secure, herbicide-approved storage.

• Have a copy of MSDSs at work site.

• Notify local emergency personnel of proposed treatments.

• Contain and clean up spills and request help as needed.

• Secure containers during transport.

• Follow label directions for use and storage.

• Dispose of unwanted herbicides promptly and correctly.

• Use the typical application rate, where feasible, when applying 2,4-D, hexazinone, and triclopyr 

to reduce risk to workers and the public. (MM)

• Limit application of chlorsulfuron via ground broadcast applications at the maximum application 

rate. (MM)

• Do not apply hexazinone with an over-the-shoulder broadcast applicator (backpack sprayer). 

(MM)

• Consideration should be given to herbicides other than 2,4-D; use of 2,4-D should be limited to 

situations where other herbicides are ineffective or in situations in which the risks posed by 2,4-D 

can be mitigated (Oregon FEIS MM).

Table D-1. Buffer Distances to Minimize Risk to Vegetation from Off-Site Drift of BLM-Evaluated Herbicides

Application

Scenario Chlorsulfuron Imazapic Diflufenzopyr + Dicamba Sulfometuron methyl

Buffer Distance (feet) from Non-target Aquatic Plants

Typical Application Rate - Low Boom1 0 0 100 900

Maximum Application Rate - Low Boom 0 0 900 900

Buffer Distance (feet) from Non-target Terrestrial Plants

Typical Application Rate - Low Boom 900 0 0 0

Maximum Application Rate - Low Boom 1,000 0 100 0

Buffer Distance (feet) from Threatened, Endangered, and Sensitive Plants

Typical Application Rate - Low Boom 1,000 0 100 1,100

Maximum Application Rate - Low Boom 1,050 0 900 1,100

1 Low boom is 20 inches above ground.

NE = Not evaluated and NA = not applicable.

Buffer distances are the smallest modeled distance at which no risk was predicted. In some cases, buffer distances were extrapolated if the 

largest distance modeled still resulted in risk, or interpolated if greater precision was required.

Table D-2. Buffer Distances to Minimize Risk to Vegetation from Off-Site Drift of Forest Service-Evaluated 

Herbicides

Application Scenario Dicamba Clopyralid Glyphosate Hexazinone Imazapyr Metsulfuron

methyl Picloram Triclopyr

Buffer Distance (feet) from Susceptible Plants1

Typical Rate - Low Boom 300 900 50 NE 900 900 >900 300

Maximum Rate - Low Boom 900 1 000 300 NE >900 >900 >900 >900

Buffer Distance (feet) from Tolerant Terrestrial Plants

Typical Rate - Low Boom 0 0 25 0 25 25 25 NE

Maximum Rate - Low Boom 0 25 25 100 50 25 25 NE

NE = Not evaluated.

Buffer distances are the smallest modeled distance at which no risk was predicted. In some cases, buffer distances were extrapolated if the 

largest distance modeled still resulted in risk, or interpolated if greater precision was required.

1 Mitigation Measures for Bureau Sensitive or federally listed species use these buffer distances
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Table D-3. Buffer Distances to Minimize Risk to Fish and Aquatic Invertebrates from Off-Site Drift of BLM-Evaluated 

Herbicides 

Application Scenario Chlorsulfuron Imazapic Diflufenzopyr + 

Dicamba Sulfometuron methyl

Minimum Buffer Distance (feet) from Fish and Aquatic Invertebrates

Typical Rate - Low Boom 0 0 0 0

Maximum Rate - Low Boom 0 0 0 0

NA Not applicable. Boom height= The Tier I ground application model allows selection of a low (20 inches) or a high (50 inches) boom height.

Table D-4. Buffer Distances (in feet) to Minimize Risk to Non-target Vegetation from Off-site Drift

Application Scenario Aminopyralid Fluroxypyr Rimsulfuron

Buffer Distance (feet) from Non-Target Terrestrial Plants

Typical Rate - Low Boom1 25 100 100

Maximum Rate - Low Boom 100 400 400

Buffer Distance (feet) from Terrestrial Threatened, Endangered, and Sensitive Plants

Typical Rate - Low Boom 100 100 100

Maximum Rate - Low Boom 400 600 400

Buffer Distance (feet) from Non-Target Aquatic Plants2

Typical Rate - Low Boom NA NA 100

Maximum Rate - Low Boom NA NA 100

Buffer distances are the smallest modeled distance at which no risk was predicted. In some cases, buffer distances were extrapolated if the 

largest distance modeled still resulted in risk, or interpolated if greater precision was required.

NA means that no buffers are required, since direct spray of plants was not predicted to result in adverse effects. However, a direct spray into 

an aquatic habitat is not an approved use of these herbicides.

1 20 inches above ground.

2 Aquatic plants in ponds and streams were considered in the Ecological Risk Assessments. The largest buffer distances are presented in this 

table.

Protection Measures for Federally Listed Species

The Northwest Oregon District has 17 federally listed species that are known or have potential to occur on the 

District (see Table D-5)21.

Table D-5. Listed Species on the Northwest Oregon District

Taxon Common Name Scientific Name Population Status

Plant Willamette valley daisy Erigeron decumbens var. 

decumbens Endangered

Plant Bradshaw’s lomatium Lomatium bradshawii Endangered

Plant Kincaid’s lupine Lupinus oreganus Threatened

Plant Nelson’s checker-mallow Sidalcea nelsoniana Threatened

Plant golden paintbrush Castilleja levisecta Threatened

Plant water howellia Howellia aquatilis Threatened

Anadromous Fish Coho salmon Oncorhynchus kisutch Oregon Coast, Lower Columbia 

River Threatened

Anadromous Fish steelhead Oncorhynchus mykiss Upper Willamette River, Lower 

Columbia River Threatened

Anadromous Fish Chinook salmon Oncorhynchus tshawytscha Upper Willamette River, Lower 

Columbia River Threatened

Anadromous Fish Pacific eulachon Thaleichthys pacificus Southern Threatened

Resident Fish bull trout Salvelinus confluentus All Threatened

Insect Fender’s blue butterfly Plebejus icarioides fenderi Endangered

Insect Taylor’s checkerspot butterfly Euphydryas editha taylori Endangered

 21 More information about the effects to these species can be found in the Issue 4 (federally listed plants), Issues 2 and 10

(federally listed fish), Issue 7 (federally listed birds), and Issue 9 (federally listed butterflies).
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Taxon Common Name Scientific Name Population Status

Insect Oregon silverspot butterfly Speyeria zerene hippolyta Threatened

Bird streaked horned lark Eremophila alpestris 

strigata Threatened

Bird northern spotted owl Strix occidentalis caurina Threatened

Bird marbled murrelet Brachyramphus 

marmoratus

Threatened

Formal and informal consultation that covers herbicides and other invasive plant treatments on the District has 

occurred with the U.S. Fish and Wildlife Service (FWS) and National Marine Fisheries Service (NMFS) on numerous 

occasions (see Table D-6). The BLM submits annual reports to the Services in compliance with these consultations 

at both the State- and District-level.

Table D-6. Endangered Species Act Consultation

Program / Biological Assessment Agency / Area Year Consultation

Vegetation Treatments Using Herbicides on BLM Lands 

in 17 Western States PEIS (USDI 2007a)

Vegetation Treatments on BLM Lands in 17 Western 

States Programmatic Environmental Report (USDI 

2007d)

Vegetation Treatments on BLM Lands in 17 Western 

States Biological Assessment (USDI 2007c)

BLM - 17 

Western States 2007

FWS Letter of Concurrence

(Reference: FWS/AES/DCHRS/027171)

NMFS Biological Opinion

(Tracking Number: FPR-2004-1502)

Vegetation Treatments Using Herbicides on BLM Lands 

in Oregon (USDI 2010a)

Vegetation Treatments on BLM Lands in 17 Western 

States Biological Assessment (USDI 2007c)

BLM - Oregon 2010

FWS Letter of Concurrence

(TAILS Number: 13420-2010-I-0173)

NMFS Biological Opinion

(Number: 2009/05539)

Aquatic Restoration Biological Assessment II (USDA et al. 

2013)

BLM and Forest 

Service - OR, 

WA, parts of CA, 

NV, and ID

2013

Aquatic Restoration Biological Opinion (ARBO 

II)

(NMFS Tracking Number: NWP-2013-9664)

(FWS Reference: 01EOFW00-2013-F-0090)

Biological Assessment for the Resource Management 

Plan for the West Eugene Wetlands in Lane County, 

Oregon on the US BLM – Eugene District (USDI 2014a)

BLM - West 

Eugene 

Wetlands

2014 Biological Opinion (FWS)

(Reference: 01EOFW00-2014-F-0139)

Biological Assessment (USDI 2016c) for Vegetation 

Treatments Using Aminopyralid, Fluroxypyr, and 

Rimsulfuron PEIS (USDI 2016a)

BLM - 17 

Western States

2015 / 

2016

FWS Letter of Concurrence

(Reference: FWS/AES/DER/BCH/061446)

NMFS Biological Opinion

(Tracking Number: PCTS FPR-2015-9121)

Endangered Species Act consultation with U.S. Fish and Wildlife Service and NMFS occurred at the national level 

with the 2007 and 2016 PEISs and at the Oregon level with the 2010 Oregon FEIS. Consultation has also been done 

with the Services for aquatic restoration work in Oregon and Washington and portions of neighboring states for 

the BLM and the Forest Service, resulting in the Aquatic Restoration Biological Opinion (ARBO II).

For the 2007 PEIS, the BLM consulted with the U.S. Fish and Wildlife Service and NMFS as required under Section 7 

of the Endangered Species Act. The BLM prepared the Biological Assessment for Vegetation Treatments on Bureau 

of Land Management Lands in 17 Western States (USDI 2007c), with a determination of “may affect, not likely to 

adversely affect.” That Biological Assessment evaluated the likely impacts to federally listed species, species 

proposed for listing, and critical habitats from the proposed use of herbicides and other treatment methods, and 

identified management practices to minimize impacts to these species and habitats.

The U.S. Fish and Wildlife Service issued a Letter of Concurrence that concurred that the proposed action as 

described in the 2007 PEIS and Biological Assessment, with all Standard Operating Procedures and PEIS Mitigation 

Measures, would not likely adversely affect any federally listed species under the jurisdiction of the U.S. Fish and 

Wildlife Service. In addition, the U.S. Fish and Wildlife Service recognized that any future site-specific actions 
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carried out under the PEIS would undergo additional consultation as appropriate (USDI 2007b). In 2010, the U.S. 

Fish and Wildlife Service reviewed the 2010 Oregon FEIS and 2007 Biological Assessment (USDI 2007c) and issued a 

similar Letter of Concurrence (USDI 2010b). In 2016, after reviewing the 2016 PEIS and Biological Assessment, the 

U.S. Fish and Wildlife Service issued a similar Letter of Concurrence (USDI 2016b).

The Biological Opinion issued by the NMFS in 2007 concluded that the proposed action as described in the 2007 

PEIS and Biological Assessment was not likely to jeopardize the continued existence of listed anadromous fish. 

There is no incidental take22 identified or exempted by the Biological Opinion. If take is anticipated for site-specific 

treatments, then the amount or extent of take will be identified during subsequent consultation for those 

proposed treatments. Similarly, the Biological Opinion issued by the NMFS in 2010 – based on the 2010 Oregon 

FEIS and 2007 Biological Assessment – concluded that the proposed action was not likely to jeopardize the 

continued existence of listed anadromous fish in the State or result in the destruction or adverse modification of 

designated critical habitat. The Biological Assessment stated that incidental take is likely but not precisely 

quantifiable (USDI 2010b:143). Hence, the NMFS concluded that, “vegetation treatments within a 1,500 feet buffer 

will undergo a site-specific consultation. Vegetation treatments outside of the 1,500-foot buffer should not result 

in take if minimization measures are used” (USDI 2010b:143). Similar to the 2007 Biological Opinion, the 2016 

Biological Opinion concluded that herbicide use was not likely to jeopardize the continued existence of 

endangered and threatened salmon and trout, threatened green sturgeon, and threatened southern resident killer 

whales and did not identify any incidental take.

The effects from terrestrial invasive plant control actions on the listed anadromous fish species present on the 

District were also analyzed in the Aquatic Restoration Biological Assessment II (ARBA II), with a determination of 

“may affect, likely to adversely affect” and were provided Endangered Species Act and Magnuson-Stevens Fishery 

Conservation Act coverage under the National Marine Fisheries Service’s Aquatic Restoration Biological Opinion 

(ARBO II, NMFS 2013).

In ARBO II, NMFS determined that the proposed action was not likely to jeopardize the continued existence of the 

coho salmon (threatened, Oregon Coast and Lower Columbia River Evolutionary Significant Units) or result in the 

destruction or adverse modification of designated critical habitat. Project Design Criteria for invasive plant control 

outlined in NMFS’s ARBO II were fully incorporated into Project Design Features of this EA, and the extent of take 

authorized in ARBO II correlates to the extent of treated areas outlined in the project design criteria of ARBO II (i.e. 

less than, or equal to, 10 percent of the acres in a riparian reserve within a sub-watershed, or 6th field Hydrologic 

Unit Code (HUC)/year). ARBO II does not cover the use of fluazifop-P-butyl, fluroxypyr, fluridone, hexazinone, or 

rimsulfuron (five of the herbicides analyzed in this analysis) nor does it cover aquatic invasive plant treatments.

In 2014, the BLM consulted with the U.S. Fish and Wildlife Service regarding management of the West Eugene 

Wetlands to contribute to the recovery of federally-listed species while providing other benefits, particularly water 

quality enhancement, and storm water and flood control, habitat for native plant and animal communities, and 

recreation and environmental education opportunities, to the extent compatible with threatened and endangered 

species management. This includes invasive plant treatments with herbicides (clopyralid, glyphosate, triclopyr, and 

limited amounts of fluazifop-p-butyl and aminopyralid) to allow for habitat enhancement and restoration. The U.S. 

Fish and Wildlife Service determined that the proposed action was not likely to jeopardize the continued existence 

nor adversely modify the critical habitat of any of the listed species present in the West Eugene Wetlands 

(Fender’s blue butterfly, Taylor’s checkerspot butterfly, streaked horned lark, Willamette daisy, Kincaid’s lupine, 

and Bradshaw’s lomatium).

Consultation resulted in the identification of Conservation Measures and Project Design Criteria to protect Districtlisted species from treatments are provided below.

 22 “Take” means to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such 

conduct (16 U.S.C. 1532(19).
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In addition, the BLM is preparing Biological Assessments. The BLM will consult with the National Marine Fisheries 

Service to address: 

• The use of fluazifop-P-butyl at distances up to 300 feet from listed anadromous fish habitat 

(Alternatives 2 and 3)

• Treatments of aquatic invasive plant infestations in waterbodies that contain federally threatened or 

endangered anadromous fish species or provide critical habitat (Alternative 3)

The BLM will consult with the U.S. Fish and Wildlife Service to address: 

• The use of fluazifop-P-butyl, rimsulfuron, fluroxypyr, and hexazinone in listed species habitat

(Alternatives 2 and 3)

• Treatments of terrestrial invasive plant infestations in Taylor’s checkerspot butterfly, Fender’s blue 

butterfly, and streaked horned lark critical habitat (Alternatives 2 and 3)

• Treatments of terrestrial invasive plant infestations in upland federally threatened or endangered

plant habitats (Alternatives 2 and 3)

The BLM would adopt any additional Project Design Criteria that result from consultation with either agency.

Conservation Measures from the 2007 and 2016 PEISs 

Biological Assessments

Mitigation Measures (above) include “when necessary to protect Special Status [plant/fish/wildlife species], 

implement all Conservation Measures for [plant/fish/wildlife species] presented in the Vegetation Treatments on 

Bureau of Land Management Lands in 17 Western States Programmatic Biological Assessment” (USDI 2007c). 

Conservation Measures for mammals, birds, arthropods, and terrestrial mollusks are generally species specific. 

Federally listed species with Conservation Measures are included below. Not all Bureau Sensitive species have 

Conservation Measures; however, Conservation Measures for similar species can be found in the 2007 and 2016 

PEIS Biological Assessments.

Given the low toxicity of aminopyralid, fluroxypyr, and rimsulfuron to fauna; likely uses of the herbicides; and, 

Standard Operating Procedures for minimizing the risk of spills, no new aquatic or terrestrial animal Conservation 

Measures have been developed for herbicide treatments using aminopyralid, fluroxypyr, or rimsulfuron. Additional 

plant Conservation Measures were adopted as part of the Biological Assessment for Vegetation Treatments Using 

Aminopyralid, Fluroxypyr, and Rimsulfuron (USDI 2016c) and are included below.

Plant Conservation Measures

As dictated in BLM Manual 6840 (Special Status Species Management), local BLM offices are required to develop 

and implement management plans and programs that will conserve listed species and their habitats. In addition, 

NEPA documentation related to treatment activities (i.e., projects) will be prepared that identify any TEP23 plant 

species or their critical habitat that are present in the proposed treatment areas, and that list the measures that 

will be taken to protect them.

The following general guidance applies to all management plans developed at the local level.

Required steps include the following:

• A survey of all proposed action areas within potential habitat by a botanically qualified biologist, botanist, 

or ecologist to determine the presence/absence of the species.

 23 Federally listed as threatened or endangered, or proposed for such listing.
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• Establishment of site-specific no activity buffers by a qualified botanist, biologist, or ecologist in areas of 

occupied habitat within the proposed project area. To protect occupied habitat, treatment activities 

would not occur within these buffers.

• Collection of baseline information on the existing condition of TEP plant species and their habitats in the 

proposed project area.

• Establishment of pre-treatment monitoring programs to track the size and vigor of TEP populations and 

the state of their habitats. These monitoring programs would help in anticipating the future effects of 

vegetation treatments on TEP plant species.

• Assessment of the need for site revegetation post treatment to minimize the opportunity for noxious 

weed invasion and establishment.

At a minimum, the following must be included in all management plans:

• Given the high risk for damage to TEP plants and their habitat from burning, mechanical treatments, and 

use of domestic animals to contain weeds, none of these treatment methods should be utilized within 

330 feet of sensitive plant populations unless the treatments are specifically designed to maintain or 

improve the existing population.

• Off-highway use of motorized vehicles associated with treatments should be avoided in suitable or 

occupied habitat.

• Biological control agents (except for domestic animals) that affect target plants in the same genus as TEP 

species must not be used to control target species occurring within the dispersal distance of the agent.

• Prior to use of biological control agents that affect target plants in the same family as TEP species, the 

specificity of the agent with respect to factors such as physiology and morphology should be evaluated, 

and a determination as to risks to the TEP species made.

• Post-treatment monitoring should be conducted to determine the effectiveness of the project.

In addition, the following guidance must be considered in all management plans in which herbicide treatments are

proposed to minimize or avoid risks to TEP species. The exact Conservation Measures to be included in 

management plans would depend on the herbicide that would be used, the desired mode of application, and the 

conditions of the site. Given the potential for off-site drift and surface runoff, populations of TEP species on lands 

not administered by the BLM would need to be considered if they are located near proposed herbicide treatment 

sites.

• Herbicide treatments should not be conducted in areas where TEP plant species may be subject to direct 

spray by herbicides during treatments.

• Applicators should review, understand, and conform to the “Environmental Hazards” section on herbicide 

labels (this section warns of known pesticide risks and provides practical ways to avoid harm to organisms 

or the environment).

• To avoid negative effects to TEP plant species from off-site drift, surface runoff, and/or wind erosion, 

suitable buffer zones should be established between treatment sites and populations (confirmed or 

suspected) of TEP plant species, and site-specific precautions should be taken (refer to the guidance 

provided below).

• Follow all instructions and Standard Operating Procedures to avoid spill and direct spray scenarios into 

aquatic habitats that support TEP plant species.

• Follow all BLM operating procedures for avoiding herbicide treatments during climatic conditions that 

would increase the likelihood of spray drift or surface runoff.

Conservation Measures were created at the National level with the 2007 and 2016 PEISs and refer to sites where 

broadcast spraying of herbicides is desired. Manual spot treatment of undesirable vegetation can occur within the 

listed buffer zones if it is determined by local biologists that this method of herbicide application would not pose 

risks to TEP plant species in the vicinity. Additional precautions during spot treatments of vegetation within 

habitats where TEP plant species occur should be considered while planning local treatment programs, and should 

be included as Conservation Measures in local-level NEPA documentation.
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The buffer distances provided below are conservative estimates, based on the information provided by Ecological 

Risk Assessments, and are designed to provide protection to TEP plants. Some Ecological Risk Assessments used 

regression analysis to predict the smallest buffer distance to ensure no risks to TEP plants. In most cases, where 

regression analyses were not performed, suggested buffers extend out to the first modeled distance from the 

application site for which no risks were predicted. In some instances, the jump between modeled distances was 

quite large (e.g., 100 feet to 900 feet). Regression analyses could be completed at the local level using the 

interactive spreadsheets developed for the Ecological Risk Assessments, using information in Ecological Risk 

Assessments and for local site conditions (e.g., soil type, annual precipitation, vegetation type, and treatment 

method), to calculate more precise, and possibly smaller buffers for some herbicides.

2,4-D

• Because the risks associated with this herbicide were not assessed, do not spray within 1⁄2 mile of 

terrestrial plant species or aquatic habitats where TEP aquatic plant species occur.

• Do not use aquatic formulations in aquatic habitats where TEP aquatic plant species occur.

• Assess local site conditions when evaluating the risks from surface water runoff to TEP plants located 

within 1⁄2-mile downgradient from the treatment area.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Aminopyralid

• If using a low boom at the typical application rate, do not apply within 100 feet of TEP terrestrial plants24.

• If using a low boom at the maximum application rate, do not apply within 400 feet of TEP terrestrial 

plants.

• In areas where wind erosion is likely, do not apply within 1.2 miles of TEP plant species (an alternative 

suitable buffer may be developed at the local level based on an analysis of site conditions).

Chlorsulfuron

• Do not apply by ground methods within 1,200 feet of terrestrial TEP species.

• Do not apply by ground methods within 25 feet of aquatic habitats where TEP plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Clopyralid

• Use only a low boom during ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant 

species or aquatic habitats in which TEP plant species occur.

• Do not apply by ground methods at the typical application rate within 900 feet of terrestrial TEP species.

• Do not apply by ground methods at the maximum application rate within 1⁄2 mile of terrestrial TEP species.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Dicamba

• If using a low boom at the typical application rate, do not apply within 1,050 feet of terrestrial TEP plant 

species.

• If using a low boom at the maximum application rate, do not apply within 1,050 feet of terrestrial TEP 

plant species.

• Do not apply within 25 feet of aquatic habitats where TEP plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

 24 Note that buffers for terrestrial plants may be appropriate for plant species that root in water but have foliage extending 

above the surface of the water.
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Diflufenzopyr

• If using a low boom at the typical application rate, do not apply within 100 feet of terrestrial TEP plant 

species.

• If using a low boom at the maximum application rate, do not apply within 900 feet of terrestrial TEP plant 

species.

• Do not apply within 25 feet of aquatic habitats where TEP plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Fluroxypyr

• If using a low boom at the typical application rate, do not apply within 100 feet of TEP terrestrial plants.

• If using a low boom at the maximum application rate, do not apply within 600 feet of TEP terrestrial 

plants.

• In areas where wind erosion is likely, do not apply within 1.2 miles of TEP plant species (an alternative 

suitable buffer may be developed at the local level based on an analysis of site conditions).

Glyphosate

• Use only a low boom during ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant 

species.

• Do not apply by ground methods at the typical application rate within 50 feet of terrestrial TEP plant 

species.

• Do not apply by ground methods at the maximum application rate within 300 feet of terrestrial TEP plant 

species.

Hexazinone

• Only apply this herbicide by ground methods using a low boom within 1⁄2 mile of terrestrial TEP plant 

species and aquatic habitats that support aquatic TEP species.

• Do not apply by ground methods at the typical application rate within 300 feet of terrestrial TEP plant 

species or aquatic habitats that support aquatic TEP plant species.

• Do not apply by ground methods at the maximum application rate within 900 feet of terrestrial TEP plant 

species or aquatic habitats that support aquatic TEP plant species.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Imazapic

• Do not apply by ground methods within 25 feet of terrestrial TEP species or aquatic habitats where TEP 

plant species occur.

Imazapyr

• Use only a low boom for ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant species 

or aquatic habitats in which TEP plant species occur.

• Do not apply at the typical application rate within 900 feet of terrestrial TEP plant species or aquatic 

habitats in which aquatic TEP species occur.

• Do not apply at the maximum application rate within 1⁄2 mile of terrestrial TEP plant species or aquatic 

habitats in which aquatic TEP species occur.

• Do not use aquatic formulations in aquatic habitats where TEP aquatic plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Metsulfuron Methyl

• Use only a low boom for ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant species 

or aquatic habitats in which TEP plant species occur.

• Do not apply at the typical application rate within 900 feet of terrestrial TEP plant species or aquatic 

habitats in which aquatic TEP species occur.
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• Do not apply at the maximum application rate within 1⁄2 mile of terrestrial TEP plant species or aquatic 

habitats in which aquatic TEP species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Diflufenzopyr + dicamba

• If using a low boom at the typical application rate, do not apply within 100 feet of terrestrial TEP plant 

species.

• If using a low boom at the maximum application rate, do not apply within 900 feet of terrestrial TEP plant 

species.

• Do not apply within 25 feet of aquatic habitats where TEP plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Picloram

• Do not apply by ground methods, at any application rate, within 1⁄2 mile of terrestrial TEP plant species.

• Assess local site conditions when evaluating the risks from surface water runoff to TEP plants located 

within 1⁄2-mile downgradient from the treatment area.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Rimsulfuron

• If using a low boom at the typical application rate, do not apply within 200 feet of TEP terrestrial plants.

• If using a low boom at the maximum application rate, do not apply within 400 feet of TEP terrestrial 

plants.

• In areas where wind erosion is likely, do not apply within 1.2 miles of TEP plant species (an alternative 

suitable buffer may be developed at the local level based on an analysis of site conditions).

• Do not use in watersheds where annual precipitation exceeds 50 inches.

• In watersheds where annual precipitation exceeds 10 inches, prior to use of rimsulfuron conduct a locallevel analysis of site conditions and develop suitable conservation measures for protection of TEP plant 

species from surface runoff.

Sulfometuron Methyl

• Do not apply by ground methods within 1,500 feet of terrestrial TEP species.

• Do not apply by ground methods within 900 feet of aquatic habitats where TEP plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Triclopyr Acid

• Use only a low boom during ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant 

species.

• Use only a low boom during ground applications at the maximum application rate of this herbicide within 

1⁄2 mile of aquatic habitats in which TEP plant species occur.

• Do not apply by ground methods at the typical application rate within 300 feet of terrestrial TEP plant 

species.

• Do not apply by ground methods at the maximum application rate within 1⁄2 mile of terrestrial TEP plant 

species or aquatic habitats in which TEP plant species occur.

• If applying to aquatic habitats in which aquatic TEP plant species occur, do not exceed the targeted water 

concentration on the product label.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

Triclopyr BEE

• Use only a low boom for ground applications of this herbicide within 1⁄2 mile of terrestrial TEP plant species 

or aquatic habitats in which TEP plant species occur.
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• Do not apply by ground methods at the typical application rate within 300 feet of terrestrial TEP plant 

species or aquatic habitats in which TEP plant species occur.

• Do not apply by at the maximum application rate within 1⁄2 mile of terrestrial TEP plant species or aquatic 

habitats in which TEP plant species occur.

• Do not use aquatic formulations in aquatic habitats where TEP aquatic plant species occur.

• In areas where wind erosion is likely, do not apply within 1⁄2 mile of TEP plant species.

If a tank mix of one of these chemicals with another approved herbicide is desired, an additional assessment of 

potential effects to non-target TEP species must be made with the assumption that effects of the herbicides are at 

a minimum additive. Larger buffers may be warranted. At the local level, the BLM must make determinations as to 

the suitability of herbicide treatments for the populations of TEP species that are managed by local offices. The 

following information should be considered: the timing of the treatment in relation to the phenology of the TEP 

plant species; the intensity of the treatment; the duration of the treatment; and the tolerance of the TEP species 

to the treatment. When information about species tolerance is unavailable or is inconclusive, local offices must 

assume an adverse effect to plant populations, and protect those populations from direct or indirect exposure to 

the treatment in question. Treatment plans must also address the presence of and expected impacts on noxious 

weeds on the project site. These plans must be coordinated with BLM weed experts and/or appropriate county 

weed supervisors to minimize the spread of weeds.

The information provided in Table 4-4 of the 2007 PEIS Biological Assessment (USDI 2007c:4-113 to 4-126) 

provides a general guideline as to the types of habitats in which treatments (particularly fire) may be utilized to 

improve growing conditions for TEP plant species. However, at the local level, the BLM must make a further 

determination as to the suitability of vegetation treatments for the populations of TEP species that are managed 

by local offices. The following information should be considered: the timing of the treatment in relation to the 

phenology of the TEP plant species; the intensity of the treatment; the duration of the treatment; and the 

tolerance of the TEP species to the particular type of treatment to be used. When information about species 

tolerance is unavailable or is inconclusive, local offices must assume a negative effect to plant populations, and 

protect those populations from direct exposure to the treatment in question.

Treatment plans must also address the presence of and expected impacts on noxious weeds on the project site. 

These plans must be coordinated with BLM weed experts and/or appropriate county weed supervisors to minimize 

the spread of weeds. In order to prevent the spread of noxious weeds and other unwanted vegetation in occupied 

or suitable habitat, the following precautions should be taken:

• Cleared areas that are prone to downy brome [cheatgrass] or other noxious weed invasions should be 

seeded with an appropriate seed mixture to reduce the probability of noxious weeds or other undesirable 

plants becoming established on the site.

• Where seeding is warranted, bare sites should be seeded as soon as appropriate after treatment, and at a 

time of year when it is likely to be successful.

• In suitable habitat for TEP species, non-native species should not be used for revegetation.

• Certified noxious weed seed free seed must be used in suitable habitat, and preference should be given to 

seeding appropriate plant species when rehabilitation is appropriate.

• Straw and hay bales used for erosion control in suitable habitat must be certified weed- and seed-free.

• Vehicles and heavy equipment used during treatment activities should be washed prior to arriving at a 

new location to avoid the transfer of noxious weeds.

When BAs are drafted at the local level for treatment programs, additional Conservation Measures may be added 

to this list. Where BLM plans that consider the effects of vegetation treatments on TEP plant species already exist, 

these plans should be consulted, and incorporated (e.g., any guidance or Conservation Measures they provide) 

into local level BAs for vegetation treatments.
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Aquatic Animals Conservation Measures

Many local BLM offices already have management plans in place that ensure the protection of these species, and 

have completed formal or informal consultations on similar treatment activities. These consultations have 

identified protection zones alongside aquatic habitats that support these species. The Conservation Measures 

discussed below are probable steps required of the BLM to ensure that vegetation treatments would minimize 

impacts to TEP species. These Conservation Measures are intended as broad guidance at the programmatic level; 

further analysis of treatment programs and species habitats at the local level is required to better reduce potential 

impacts from proposed vegetation treatments. Completion of consultation at the local level will fine-tune 

Conservation Measures associated with treatment activities and ensure consistency of the treatments with ESA 

requirements.

The aquatic TEP species considered in the programmatic BA occur in varied habitats, over a large geographic area. 

The Conservation Measures guidance presented below is intended to apply broadly to aquatic species and habitats 

over the entire region covered by the BA, based on the common features found in nearly all aquatic and riparian 

habitats. Some species with alternate or unusual habitat requirements may require additional Conservation 

Measures to ensure a Not Likely to Adversely Affect determination at the local level. Such additional Conservation 

Measures are outside the scope of the BA, and will be completed at the local level.

Some local BLM plans have delineated protected riparian areas, or portions of watersheds where ripariandependent resources receive primary emphasis, and management activities are subject to specific standards and 

guidelines. These protected riparian areas include traditional riparian corridors, wetlands, intermittent streams, 

and other areas that help maintain the integrity of aquatic ecosystems by 1) influencing the delivery of coarse 

sediment, organic matter, and woody debris to streams; 2) providing root strength for channel stability; 3) shading 

the stream; and 4) protecting water quality. Examples of protected riparian areas are the BLM’s Riparian Reserves 

of the Pacific Northwest. The term “riparian areas,” as used in the Conservation Measures guidance below, refers 

to riparian protected areas, wherever such designations apply. However, since not all local BLM plans have made 

such designations, “riparian areas,” when the above-mentioned use is not applicable, generally refers to: 1) for 

streams, the stream channel and the extent of the 100-year floodplain; and 2) for wetlands, ponds, and lakes, and 

other aquatic habitats, the area extending to the edges of the riparian vegetation, provided it is no less than the 

minimum buffer distance for a given site established by local BLM biologists.

Conservation Measures for Site Access and Fueling/Equipment Maintenance

For treatments occurring in watersheds with TEP species or designated or undesignated critical habitat (i.e., 

unoccupied habitat critical to species recovery):

• Where feasible, access work site only on existing roads, and limit all travel on roads when damage to the 

road surface will result or is occurring.

• Where TEP aquatic species occur, consider ground-disturbing activities on a case by case basis, and 

implement Standard Operating Procedures to ensure minimal erosion or impact to the aquatic habitat.

• Within riparian areas, do not use vehicle equipment off of established roads.

• Outside of riparian areas, allow driving off of established roads only on slopes of 20% or less.

• Within 150 feet of wetlands or riparian areas, do not fuel/refuel equipment, store fuel, or perform 

equipment maintenance (locate all fueling and fuel storage areas, as well as service landings outside of 

protected riparian areas).

• Do not conduct biomass removal (harvest) activities that will alter the timing, magnitude, duration, and 

spatial distribution of peak, high, and low flows outside the range of natural variability.
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Conservation Measures Related to Revegetation Treatments

• Outside riparian areas, avoid hydro-mulching within buffer zones established at the local level. This 

precaution will limit adding sediments and nutrients and increasing water turbidity.

• Within riparian areas, engage in consultation at the local level to ensure that revegetation activities 

incorporate knowledge of site-specific conditions and project design.

Conservation Measures Related to Herbicide Treatments

The complexity of this action within riparian areas requires local consultation, which will be based on herbicide 

Risk Assessments.

Possible Conservation Measures:

• Maintain equipment used for transportation, storage, or application of chemicals in a leak proof 

condition.

• Do not store or mix herbicides, or conduct post-application cleaning within riparian areas.

• Ensure that trained personnel monitor weather conditions at spray times during application.

• Strictly enforce all herbicide labels.

• Do not broadcast spray within 100 feet of open water when wind velocity exceeds 5 mph.

• Do not broadcast spray when wind velocity exceeds 10 mph.

• Do not spray if precipitation is occurring or is imminent (within 24 hours).

• Do not broadcast spray herbicides in riparian areas that provide habitat for TEP aquatic species. 

Appropriate buffer distances should be determined at the local level to ensure that overhanging 

vegetation that provides habitat for TEP species is not removed from the site. Buffer distances provided as 

Conservation Measures in the assessment of effects to plants and fish and aquatic invertebrates should 

be consulted as guidance. (Note: the Forest Service did not determine appropriate buffer distances for 

TEP fish and aquatic invertebrates when evaluating herbicides in Forest Service Ecological Risk 

Assessments; buffer distances were only determined for non-TEP species.)

• Do not use terrestrial formulations of glyphosate, or triclopyr BEE, to treat aquatic vegetation in habitats 

where aquatic TEP species occur or may potentially occur.

• Follow all instructions and Standard Operating Procedures to avoid spill and direct spray scenarios into 

aquatic habitats. Special care should be followed when transporting and applying 2,4-D, clopyralid, 

glyphosate, hexazinone, imazapyr, metsulfuron methyl, picloram, and triclopyr.

• Do not broadcast spray glyphosate, picloram, or triclopyr BEE in upland habitats adjacent to aquatic 

habitats that support (or may potentially support) aquatic TEP species under conditions that would likely 

result in off-site drift.

• In watersheds that support TEP species or their habitat, do not apply triclopyr BEE in upland habitats 

within 1⁄2 mile upslope of aquatic habitats that support aquatic TEP species under conditions that would 

likely result in surface runoff.

Numerous Conservation Measures were developed from information provided in Ecological Risk Assessments. The 

measures listed below would apply to TEP fish and other aquatic species at the programmatic level in all 17 

western states. However, local BLM field offices could use interactive spreadsheets and other information 

contained in the Ecological Risk Assessments to develop more site-specific Conservation Measures and 

management plans based on local conditions (soil type, rainfall, vegetation type, and herbicide treatment method). 

It is possible that Conservation Measures would be less restrictive than those listed below if local site conditions 

were evaluated using the Ecological Risk Assessments when developing project-level Conservation Measures.
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Conservation Measures Related to Prescribed Fire

Within riparian areas, in watersheds with TEP species or their habitats:

• Conduct prescribed burning only when long-term maintenance of the riparian area is the primary 

objective, and where low intensity fires can be maintained.

• Do not construct black lines, except by non-mechanized methods.

• Utilize/create only the following firelines: natural barriers; hand-built lines parallel to the stream channel 

and outside of buffer zones established at the local level; or hand built lines perpendicular to the stream 

channel with waterbars and the same distance requirement.

• Do not ignite fires using aerial methods.

• In forested riparian areas, keep fires to low severity levels to ensure that excessive vegetation removal 

does not occur.

• Do not camp, unless allowed by local consultation.

• Have a fisheries biologist determine whether pumping activity can occur in streams with TEP species.

• During water drafting/pumping, maintain a continuous surface flow of the stream that does not alter 

original wetted stream width.

• Do not alter dams or channels in order to pump in streams occupied by TEP species.

• Do not allow helicopter dipping from waters occupied by TEP species, except in lakes outside of the 

spawning period.

• Consult with a local fisheries biologist prior to helicopter dipping in order to avoid entrainment and 

harassment of TEP species.

Conservation Measures Related to Mechanical Treatments

Note: these measures apply only to treatments occurring in watersheds that support TEP species or in unoccupied 

habitat critical to species recovery (including but not limited to critical habitat, as designated by U.S. Fish and 

Wildlife Service).

Outside riparian areas in watersheds with TEP species or designated or undesignated critical habitat (i.e., 

unoccupied habitat critical to species recovery):

• Conduct soil-disturbing treatments only on slopes of 20% or less, where feasible.

Within riparian areas in these watersheds, more protective measures will be required to avoid negatively affecting 

TEP species or their habitat:

• Do not use vehicles or heavy equipment, except when crossing at established crossings.

• Do not conduct ground disturbing activities (e.g., disking, drilling, chaining, and plowing).

• Ensure that all mowing follows guidance to avoid negative effects to streambanks and riparian vegetation 

and major effects to streamside shade.

• Do not use equipment in perennial channels or in intermittent channels with water, except at crossings 

that already exist.

• Leave suitable quantities (to be determined at the local level) of excess vegetation and slash on site.

• Do not completely remove trees and shrubs.

Conservation Measures Related to Biological Control Treatments using Livestock

For treatments occurring in watersheds that support TEP species or in critical habitat:

• Where terrain permits, locate stock handling facilities, camp facilities, and improvements at least 300 feet 

from lakes, streams, and springs.

• Educate stock handlers about at-risk fish species and how to minimize negative effects to the species and 

their associated habitat.
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• Employ appropriate dispersion techniques to range management, including judicial placement of 

saltblocks, troughs, and fencing, to prevent damage to riparian areas but increase weed control.

• Equip each watering trough with a float valve.

Within riparian areas of these watersheds, more protective measures are required.

• Do not conduct weed treatments involving domestic animals, except where it is determined that these 

treatments will not damage the riparian system, or will provide long-term benefits to riparian and 

adjacent aquatic habitats.

• Do not locate troughs, storage tanks, or guzzlers near streams with TEP species, unless their placement 

will enhance weed-control effectiveness without damaging the riparian system.

Terrestrial Animals

Butterfly or Moth Conservation Measures

Many local BLM offices already have management plans in place that ensure the protection of these species during 

activities on public lands. The following Conservation Measures are the minimum steps required of the BLM to 

ensure that treatment methods would be unlikely to negatively affect TEP species.

Each local BLM office is required to draw up management plans related to treatment activities that identify any 

TEP butterfly or moth species or their critical habitat that are present in the proposed treatment areas, as well as 

the measures that will be taken to protect these species.

Management plans should, at a minimum, follow this general guidance:

• Use an integrated pest management approach when designing programs for managing pest outbreaks.

• Survey treatment areas for TEP butterflies/moths and their host/nectar plants (suitable habitat) at the 

appropriate times of year.

• Minimize the disturbance area with a pre-treatment survey to determine the best access routes. Areas 

with butterfly/moth host plants and/or nectar plants should be avoided.

• Minimize mechanical treatments and OHV activities on sites that support host and/or nectar plants.

• Carry out vegetation removal in small areas, creating openings of 5 acres or less in size.

• Avoid burning all of a species’ habitat in any 1 year. Limit area burned in butterfly/moth habitat in such a 

manner that the unburned units are of sufficient size to provide a refuge for the population until the 

burned unit is suitable for recolonization. Burn only a small portion of the habitat at any one time, and 

stagger timing so that there is a minimum 2-year recovery period before an adjacent parcel is burned.

• Where feasible, mow or wet around patches of larval host plants within the burn unit to reduce impacts 

to larvae.

• In TEP butterfly/moth habitat, burn while butterflies and/or moths of concern are in the larval stage, 

when the organisms would receive some thermal protection.

• Wash equipment before it is brought into the treatment area.

• Use a seed mix that contains host and/or nectar plant seeds for road/site reclamation.

• To protect host and nectar plants from herbicide treatments, follow recommended buffer zones and 

other Conservation Measures for TEP plants species when conducting herbicide treatments in areas 

where populations of host and nectar plants occur.

• Do not broadcast spray herbicides in habitats occupied by TEP butterflies or moths; do not broadcast 

spray herbicides in areas adjacent to TEP butterfly/moth habitat under conditions when spray drift onto 

the habitat is likely.

• Do not use 2,4-D in TEP butterfly/moth habitat.
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• When conducting herbicide treatments in or near habitat used by TEP butterflies or moths, avoid use of 

the following herbicides, where feasible: clopyralid, glyphosate, hexazinone, imazapyr, picloram, and 

triclopyr.

• If conducting manual spot applications of glyphosate, hexazinone, or triclopyr to vegetation in TEP 

butterfly or moth habitat, utilize the typical, rather than the maximum, application rate.

Bird Conservation Measures

Sand Nesters: Western Snowy Plover, Piping Plover, Least Tern and Streaked Horned Lark25

• Survey for western snowy plovers, piping plovers, interior least terns and streaked horned larks(and their 

nests) in suitable areas on proposed treatment areas, prior to developing treatment plans.

• Do not treat vegetation in nesting areas during the breeding season (as determined by a qualified 

biologist).

• Do not allow human (or domestic animal) disturbance within 1⁄4 mile of nest sites during the nesting 

period.

• Ensure that nest sites are at least 1 mile from downwind smoke effects during the nesting period.

• Conduct beachgrass treatments during the plant’s flowering stage, during periods of active growth.

• Closely follow all application instructions and use restrictions on herbicide labels; in wetland habitats use 

only those herbicides that are approved for use in wetlands.

Mature-forest Nesters: Marbled Murrelet, Northern Spotted Owl

• Survey for marbled murrelets and northern spotted owls (and their nests) on suitable proposed treatment 

areas, prior to developing treatment plans.

• Delineate a 100-acre buffer around nests prior to mechanical treatments or prescribed burns.

• Do not allow human disturbance within 1⁄4 mile of nest sites during the nesting period (as determined by a 

local biologist).

• Ensure that nest sites are at least 1 mile from downwind smoke effects during the nesting period.

• Protect and retain the structural components of known or suspected nest sites during treatments; 

evaluate each nest site prior to treatment and protect it in the most appropriate manner.

• Maintain sufficient dead and down material during treatments to support spotted owl prey species 

(minimums would depend on forest types, and should be determined by a wildlife biologist).

• Do not conduct treatments that alter forest structure in old-growth stands.

• Do not use 2,4-D in marbled murrelet or northern spotted owl habitats; do not broadcast spray 2,4-D 

within 1⁄4 mile of marbled murrelet or northern spotted owl habitat.

• Where feasible, avoid use of the following herbicides in northern spotted owl habitat: clopyralid, 

glyphosate, imazapyr, metsulfuron methyl, picloram, and triclopyr.

• Where feasible, avoid use of the following herbicides in marbled murrelet habitat: clopyralid, glyphosate, 

hexazinone, imazapyr, metsulfuron methyl, picloram, and triclopyr.

• Do not broadcast spray clopyralid, glyphosate, hexazinone, picloram, or triclopyr in marbled murrelet or 

northern spotted owl habitat; do not broadcast spray these herbicides in areas adjacent to marbled 

murrelet or northern spotted owl habitat under conditions when spray drift onto the habitat is likely.

• If broadcast spraying imazapyr or metsulfuron methyl in or adjacent to marbled murrelet, northern 

spotted owl habitat, apply at the typical, rather than the maximum, application rate.

• If broadcast spraying bromacil or diquat in or adjacent to northern spotted owl habitat, apply at the 

typical, rather than the maximum, application rate.

• If conducting manual spot applications of glyphosate hexazinone, or triclopyr to vegetation in marbled 

murrelet, or northern spotted owl habitat, utilize the typical, rather than the maximum, application rate.

 25 Of these sand nesting bird species, only the streaked horned lark is suspected or documented on the Northwest Oregon 

District.
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• Follow all instructions and SOPs to avoid spill and direct spray scenarios into aquatic habitats, particularly 

marine habitats where murrelets forage for prey.

Essential Fish Habitat Conservation Measures

Conservation Measures have been incorporated into the action alternatives to reduce negative effects to the point 

where they do not reduce the quantity or quality of essential fish habitat (EFH). For the purposes of developing 

Conservation Measures for salmon, riparian areas include traditional riparian corridors, wetlands, intermittent 

streams, and other areas that help maintain the integrity of aquatic ecosystems by 1) influencing the delivery of 

coarse sediment, organic matter, and woody debris to streams, 2) providing root strength for channel stability, 3) 

shading the stream, and 4) protecting water quality.

Activities associated with the proposed vegetation treatments would have the potential to negatively affect 

salmonids, pelagic fish and groundfish, and Alaskan crabs and scallops and their habitat. Implementation of the 

measures listed below would minimize these potential impacts to a negligible level such that the quantity and 

quality of EFH is not reduced.

General Measures

• Establish riparian, estuarine, and coastal buffer strips adjacent to salmonid, groundfish and 

pelagic fish, and Alaskan crab and scallop habitats to reduce direct impacts to the various life 

stages of these species. Buffers widths should depend on the specific ecological function for 

which protection is desired (e.g., streambanks stabilization, control of sediment inputs from 

surface erosion, or maintenance of shade to stream channels). Local BLM field offices would 

consult BLM and Forest Service Ecological Risk Assessments prepared for the BA and PEIS to 

obtain programmatic guidance on appropriate buffer distances. Field offices can also input 

information on local site conditions (e.g., soil type, vegetation type, precipitation, treatment 

method) into interactive spreadsheets developed for the Ecological Risk Assessments to develop 

more site-specific, and in most cases less restrictive, buffers for individual projects.

• Implement Standard Operating Procedures to minimize sedimentation and disturbance of 

riparian, estuarine, and coastal vegetation.

• To avoid erosion and future recreational uses within close vicinity of aquatic areas, limit or 

exclude construction of new permanent or temporary roads within the boundary of treatment 

riparian areas.

• Where possible, to avoid increased instream sedimentation, choose low-intensity burns and 

manual treatment methods over mechanical treatment methods and use of domestic animals.

Prescribed Burning Treatments

• Where feasible, avoid ignition of fires within buffer strips.

Mechanical Treatments

• Minimize the use of mechanical treatment methods (including timber harvest and timber 

salvage) within buffer strips.

• To avoid damaging potential spawning areas, do not use mechanical equipment in perennial 

channels, or in intermittent channels with water, except at crossings that already exist. Do not 

use mechanical equipment in estuaries.

Herbicide Treatments

• Where feasible, minimize spray operations around aquatic habitats to days when winds are > 10 

miles per hour for ground applications, to avoid wind drift or direct application of herbicides into 

these habitats.
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• Where feasible, minimize the use of terrestrial herbicides in watersheds with downgradient 

ponds and streams if potential impacts to salmonids are of concern.

• Time herbicide applications near salmonid-bearing streams, and estuaries and coastal/marine 

habitats used by salmon and FMP [Fishery Management Plan] species so that they do not overlap 

with sensitive life-history stages of these fish (would vary at the local level).

Biological Treatments

• In watersheds that support salmonids or that flow into watersheds where salmonids occur, to 

minimize the cumulative effect of grazing in areas that have been burned, do not conduct weed 

control by domestic animals in burned areas until they have recovered enough to control ash and 

sediment produced by the treatment.

• Prohibit livestock grazing in estuaries.

Project Design Criteria for Listed Species from ARBO II (NMFS 

2013, USDI 2013a)

Project Design Criteria established through consultation with NMFS and U.S. Fish and Wildlife Service are adopted 

for federally listed species for the analysis in this EA. The Project Design Criteria are taken from:

• National Marine Fisheries Service. 2013. Endangered Species Act – Section 7 Programmatic Consultation 

Conference and Biological Opinion and Magnuson-Stevens Fishery Conservation and Management Act 

Essential Fish Habitat Response for Reinitiation of Aquatic Restoration Activities in States of Oregon and 

Washington (ARBO II). NMFS Consultation Number: NWR-2013-9664 (NMFS 2013)

• USDI Fish and Wildlife Service. 2013. Endangered Species Act - Section 7 Consultation Programmatic 

Biological Opinion for Aquatic Restoration Activities in the States of Oregon, Washington and portions of 

California, Idaho and Nevada (ARBO II), FWS Reference: 01EOFW00-2013-F-0090 (USDI 2013a)

Text (in gray italics) was added to the ARBO II Project Design Criteria below for clarification purposes

Listed Anadromous Fish (NMFS 2013)

1.3 Proposed Action

1.3.1 Program Administration

33. Nonnative Invasive Plant Control includes manual, mechanical, biological, and chemical 

methods to remove invasive nonnative plants within Riparian Reserves, Riparian Habitat 

Conservation Areas, or equivalent and adjacent uplands. In monoculture areas (e.g., areas 

dominated by blackberry or knotweed) heavy machinery can be used to help remove invasive 

plants. This activity is intended to improve the composition, structure, and abundance of native 

riparian plant communities important for bank stability, stream shading, LW [large wood], and 

other organic inputs into streams, all of which are important elements to fish habitat and water 

quality. Manual and hand-held equipment will be used to remove plants and disperse chemical 

treatments. Heavy equipment, such as bulldozers, can be used to remove invasive plants, 

primarily in areas with low slope values. (Invasive plant treatments included in this opinion are to 

serve BLM, USFS [Forest Service], and BIA administrative units until such units complete a local 

or provincial consultation for this activity type.)

a) Project Extent – Nonnative invasive plant control projects will not exceed 10% of acres 

within a Riparian Reserve under the Northwest Forest Plan (USDA and USDI 1994b) or 

RHCA under PACFISH/INFISH (USDA 1995b; USDA and USDI 1995) within a 6th 

HUC/year.

b) Manual Methods – Manual treatments are those done with hand tools or hand held 

motorized equipment. These treatments typically involve a small group of people in a 
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localized area. Vegetation disturbance varies from cutting or mowing to temporarily 

reduce the size and vigor of plants to removal of entire plants. Soil disturbance is 

minimized by managing group size and targeting individual plants.

c) Mechanical Methods – Mechanical treatments involve the use of motorized equipment 

and vary in intensity and impact from mowing to total vegetation removal and soil 

turnover (plowing and seed bed preparation). Mechanical treatments reduce the 

number of people treating vegetation. Impacts could be lessened by minimizing the use 

of heavy equipment in riparian areas, avoiding treatments that create bare soil in large 

or extensive areas, reseeding and mulching following treatments, and avoiding work 

when soils are wet and subject to compaction.

d) Biological Methods – Release of traditional host specific biological control agents 

(insects and pathogens) consists of one or two people depositing agents on target 

vegetation. This results in minimal impact to soils and vegetation from the actual 

release. Over time, successful biological control agents will reduce the size and vigor of 

host noxious weeds with minimal or no impact to other plant species.

e) Chemical Methods – Invasive plants, including state-listed noxious weeds, are 

particularly aggressive and difficult to control and may require the use of herbicides for 

successful control and restoration of riparian and upland areas. Herbicide treatments 

vary in impact to vegetation from complete removal to reduced vigor of specific plants. 

Minimal impacts to soil from compaction and erosion are expected.

i. General Guidance

1. Use herbicides only in an integrated weed or vegetation management context 

where all treatments are considered and various methods are used individually 

or in concert to maximize the benefits while reducing undesirable effects.

2. Carefully consider herbicide impacts to fish, wildlife, non-target native plants, 

and other resources when making herbicide choices.

3. Treat only the minimum area necessary for effective control.

4. Herbicides may be applied by selective, hand-held, backpack, or broadcast 

equipment in accordance with state and Federal law and only by certified and 

licensed applicators to specifically target invasive plant species.

5. Herbicide application rates will follow label direction, unless site- specific 

analysis determines a lower maximum rate is needed to reduce non-target 

impacts.

6. An herbicide safety/spill response plan is required for all projects to reduce the 

likelihood of spills, misapplication, reduce potential for unsafe practices, and to 

take remedial actions in the event of spills. Spill plan contents will follow 

agency direction.

7. Pesticide applicator reports must be completed within 24 hours of application.

ii. Herbicide Active Ingredients – Active ingredients are restricted to the following 

(some common trade names are shown in parentheses; use of trade names does 

not imply endorsement by the US government):26

1. aminopyralid (e.g., terrestrial: Milestone VM)

2. chlorsulfuron (e.g., terrestrial: Telar, Glean, Corsair) (c) clopyralid (e.g., 

terrestrial: Transline)

3. clopyralid (e.g., terrestrial: Transline)

4. dicamba (e.g., terrestrial: Vanquish, Banvel)

5. diflufenzopyr + dicamba (e.g., terrestrial: Overdrive)

 26 The use of trade, firm, or corporation names in this opinion is for the information and convenience of the action agency and 

applicants and does not constitute an official endorsement or approval by the U.S. Department of the Interior or U.S. Fish and 

Wildlife Service of any product or service to the exclusion of others that may be suitable.
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6. glyphosate (e.g., aquatic: Aquamaster, AquaPro, Rodeo, Accord) (g) imazapic 

(e.g., terrestrial: Plateau)

7. imazapic (e.g., terrestrial: Plateau)

8. imazapyr (e.g., aquatic: Habitat; terrestrial: Arsenal, Chopper)

9. metsulfuron methyl (e.g., terrestrial: Escort)

10. picloram (e.g., terrestrial: Tordon, Outpost 22K)

11. sethoxydim (e.g., terrestrial: Poast, Vantage)

12. sulfometuron methyl (e.g., terrestrial: Oust, Oust XP)

13. triclopyr (e.g., aquatic: Garlon 3A, Tahoe 3A, Renovate 3, Element 3A; 

terrestrial: Garlon 4A, Tahoe 4E, Pathfinder II)

14. 2,4-D (e.g., aquatic: 2,4-D Amine, Clean Amine; terrestrial: Weedone, Hi-Dep)

iii. Herbicide Adjuvants – When recommended by the label, an approved aquatic 

surfactant would be used to improve uptake. When aquatic herbicides are required, 

the only surfactants and adjuvants permitted are those allowed for use on aquatic 

sites, as listed by the Washington State Department of Ecology: 

http://www.ecy.wa.gov/programs/wq/pesticides/regpesticides.html. (Oregon 

Department of Agriculture also often recommends this list for aquatic site 

applications). The surfactants R-11, Polyethoxylated tallow amine (POEA), and 

herbicides that contain POEA (e.g., Roundup) will not be used.

iv. Herbicide Carriers – Herbicide carriers (solvents) are limited to water or specifically 

labeled vegetable oil.

v. Herbicide Mixing – Herbicides will be mixed more than 150 feet from any natural 

waterbody to minimize the risk of an accidental discharge. Impervious material will 

be placed beneath mixing areas in such a manner as to contain any spills associated 

with mixing/refilling. Spray tanks shall be washed further than 300 feet away from 

surface water. All hauling and application equipment shall be free from leaks and 

operating as intended.

vi. Herbicide Application Methods – Liquid forms of herbicides will be applied as 

follows:

1. Broadcast spraying using booms mounted on ground-based vehicles27 (this 

consultation does not include aerial applications).

2. Spot spraying with hand held nozzles attached to back pack tanks or vehicles 

and hand-pumped sprayers to apply herbicide directly onto small patches or 

individual plants.

3. Hand/selective through wicking and wiping, basal bark, frill (“hack and squirt”), 

stem injection, or cut-stump.

4. Dyes or colorants, (e.g., Hi-Light, Dynamark) will be used to assist in treatment 

assurance and minimize over-spraying within 100 feet of live water.

vii. Minimization of Herbicide Drift and Leaching – Herbicide drift and leaching will be 

minimized as follows:

1. Do not spray when wind speeds exceed 10 miles per hour to reduce the 

likelihood of spray/dust drift. Winds of 2 mph or less are indicative of air 

inversions. The applicator must confirm the absence of an inversion before 

proceeding with the application whenever the wind speed is 2 mph or less.

2. Be aware of wind directions and potential for herbicides to affect aquatic 

habitat area downwind.

3. Keep boom or spray as low as possible to reduce wind effects. (d) Avoid or 

minimize drift by utilizing appropriate equipment and settings (e.g., nozzle 

selection, adjusting pressure, drift reduction agents, etc.). Select proper 

application equipment (e.g., spray equipment that produces 200-800 micron 

 27 Broadcast spraying in this EA is described as potentially occurring with a backpack sprayer or other handheld device. 
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diameter droplets [Spray droplets of 100 microns or less are most prone to 

drift]).

4. Follow herbicide label directions for maximum daytime temperature permitted 

(some types of herbicides volatilize in hot temperatures).

5. Do not spray during periods of adverse weather conditions (snow or rain 

imminent, fog, etc.). Wind and other weather data will be monitored and 

reported for all pesticide applicator reports.

6. Herbicides shall not be applied when the soil is saturated or when a 

precipitation event likely to produce direct runoff to fish-bearing waters from a 

treated site is forecasted by NOAA National Weather Service or other similar 

forecasting service within 48 hours following application. Soil-activated 

herbicides can be applied as long as label is followed. Do not conduct any 

applications during periods of heavy rainfall.

viii. Herbicide buffer distances – The following no-application buffers— which are 

measured in feet and are based on herbicide formula, stream type, and application 

method—will be observed during herbicide applications (Table D-7). Herbicide 

applications based on a combination of approved herbicides will use the most 

conservative buffer for any herbicide included. Buffer widths are measured as map 

distance perpendicular to the bankfull for streams, the upland boundary for 

wetlands, or the upper bank for roadside ditches.

Table D-7. No-application buffer widths in feet for herbicide application, by stream types and application methods

Herbicide

Perennial Streams and Wetlands, and 

Intermittent Streams and Roadside Ditches 

with flowing or standing water present

Dry Intermittent Streams, Dry Intermittent 

Wetlands, Dry Roadside Ditches

Broadcast 

Spraying1

Spot 

Spraying

Hand 

Selective

Broadcast 

Spraying1

Spot 

Spraying

Hand 

Selective

Labeled for Aquatic Use

Aquatic Glyphosate 100 waterline waterline 50 0 0

Aquatic Imazapyr 100 waterline waterline 50 0 0

Aquatic Triclopyr-TEA Not Allowed 15 waterline Not Allowed 0 0

Aquatic 2,4-D (amine) 100 waterline waterline 50 0 0

Low Risk to Aquatic Organisms

Aminopyralid 100 waterline waterline 50 0 0

Dicamba 100 15 15 50 0 0

Dicamba + diflufenzopyr 100 15 15 50 0 0

Imazapic 100 15 bankfull 

elevation 50 0 0

Clopyralid 100 15 bankfull 

elevation 50 0 0

Metsulfuron methyl 100 15 bankfull 

elevation 50 0 0

Moderate Risk to Aquatic Organisms

Imazapyr 100 50 bankfull 

elevation 50 15 bankfull elevation

Sulfometuron-methyl 100 50 5 50 15 bankfull 

elevation

Chlorsulfuron 100 50 bankfull 

elevation 50 15 bankfull elevation

High Risk to Aquatic Organisms

Triclopyr-BEE Not Allowed 150 150 Not Allowed 150 150

Picloram 100 50 50 100 50 50

Sethoxydim 100 50 50 100 50 50

2,4-D (ester) 100 50 50 100 50 50
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1 Including broadcast spraying with a backpack sprayer or other handheld sprayers.

Listed Terrestrial and Fish Species (USDI 2013a)

1.4 General Conservation Measures and Project Design Criteria for All Terrestrial and Fish Species

1. The following CMs apply to all listed terrestrial species for all programmatic activities: 

a. Aquatic restoration actions will not remove or downgrade suitable habitat (on either public or private 

land) for any listed terrestrial species. 

b. Effects of danger tree removal will be either discountable or insignificant to ESA-listed terrestrial 

species and their critical habitat. 

c. All restoration activities must have the unit’s botanist and terrestrial wildlife biologist input/analysis of 

the project design and their site-specific species assessment to proceed. This includes a plant survey 

and nest analysis (or survey if deemed appropriate by the unit biologist, and suitable habitat is known 

to occur within the project prior to project implementation). 

d. There will be no disturbance allowed from blasting activities as they are not part of the proposed 

action. 

e. The unit wildlife biologist is responsible for ensuring that the correct effects determination is made for 

each project. The unit wildlife biologist may increase or decrease disturbance distances according to the 

best available scientific information and site-specific conditions. Refer to Tables D-10 and D-11. For 

instance, if a known spotted owl site is surveyed to protocol and the owls are determined to be nonnesting, the unit biologist may determine that no disturbance or disruption would occur and lift the 

associated restrictions on activities within disruption distances during the year of survey.

Table D-8. Disturbance Distances and Time Periods When Disturbance (and Possibly Disruption) May Occur for 

Terrestrial Species*

Species Disturbance Distance (in miles) Time Period Applicable

Northern spotted owl (nesting) See Table D-10 Mar 1 – September 30

Marbled murrelet (nesting) See Table D-11 Apr 1 – Sept 15***

All Plants 0.25** Jan 1 – Dec 31

*See PDCs below for additional details. **If project is within 0.25 mile of a listed plant, then measures must be taken to minimize 

threats to NE or NLAA the species to be covered by this programmatic consultation.

***General Conservation Measure MM1 requires daily timing restrictions. The first work restriction stops two hours after sunrise and 

the work restriction starts again 2 hours before sunset.

Listed Plants (USDI 2013a)

1.4.3. Plants: For threatened or endangered plant species that may occur in project areas within the 

scope of this ARBO II, the following criteria will be applied:

a. All Listed Plant Species

i. PL1: A unit botanist will have the following input in all project designs: (a) the botanist 

will determine whether there are known listed plants or suitable habitat for listed plants 

in the project area; (b) If a known site of a listed plant is within 0.25-mile of the project 

action area, or that suitable or potential habitat may be affected by project activities, 

then a botanist will conduct a site visit/vegetation survey to determine whether listed 

plants are within the project area. This visit and survey will be conducted at the 

appropriate time of year to identify the species and determine whether individual listed 

plants or potential habitat are present and may be adversely affected by project 

activities (see Table D-9).

ii. PL2: If one or more listed plants are present and likely to be adversely affected by the 

project, then the project is not covered by this BO and consultation with the FWS under 

Section 7 of the ESA must be initiated. If a project will have no effect or is NLAA listed 

plants it is covered under this ARBA II. Project design criteria should address both the 
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critical life cycle of listed plant species as well as the effective biotic and abiotic 

environmental factors sustaining rare plant taxa.

iii. PL3: Due to soil disturbance that may occur during aquatic restoration activities and use 

of heavy equipment that could carry seeds and plant parts into project areas, all 

appropriate prevention measures will be incorporated into contract or equipment rental 

agreements to avoid introduction of invasive plants and noxious weeds into project 

areas.

Table D-9. Optimal Survey Times for Flowering Periods of Listed Plants in Oregon and Washington

Species Optimal Survey Time Period1

Bradshaw’s lomatium April to mid-May

Golden paintbrush April to September

Kincaid’s lupine May through June

Nelson’s checker-mallow Late May to Mid-July

Water Howellia June through August

Willamette valley daisy Mid-June to early July

1. This is a guideline. The local botanist will survey when the time is appropriate

Listed Insects (USDI 2013a)

1.4.4. Insects: To avoid adverse effects to Fenders blue butterfly the following will be applied:

a. Fenders Blue Butterfly

i. FBB1: No project included in this assessment will remove or disturb Kincaid’s lupine, spur lupine 

(Lupinus laxiflorus = L. arbustus) or sickle- keeled lupine (L. albicaulis) within the range of the 

Fender’s blue butterfly.

ii. FBB2: No project included in the assessment will remove habitat including the following nectar 

sources: wild onion (Allium amplectans); cat’s ear mariposa lily (Calachortus tolmiei); common 

camas (Camassia quamash); Oregon sunshine (Eriophyllum lanatum); and rose checkermallow 

(Sidalcea virgata) within the range of the Fender’s blue butterfly.

Listed Fish (USDI 2013a)

1.4.5. Fish: To lesson adverse effects to bull trout the following measures will be applied:

b. Bull Trout

i. Projects that would expose populations of bull trout to non-native fish such as brook trout or 

brown trout where such exposure does not currently exist must be approved by the USFWS 

Division or Field Manager.

ii. The driving of steel or concrete piles within the wetted width of a stream or within the wetted 

area of a lake are not covered under this BO. Ifsteel or concrete piles are to be driven adjacent 

to bull trout SR habitat, the action agencies will work with the USFWS Level 1 Team member to 

determine what (if any) site-specific PDCs or CMs are needed to reduce potential impacts to bull

trout.

Listed Birds (USDI 2013a)

1.4.6. Birds: ARBO II attempts to minimize or avoid adverse effects to listed birds by implementing aquatic 

restoration actions outside of critical nesting period windows and/or outside of disturbance or disruption 

distances from occupied habitat. However, some aquatic restoration activities must occur within a listed 

bird critical nesting period or within a disturbance or disruption distance. A limited number of aquatic 

restoration activities that adversely affect listed birds will therefore occur under this proposed action.

a. Conditions common to all programmatic activities that will be applied to avoid disturbance or 

disruption of listed bird species include:
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i. The proposed activities included in this document are consistent with the Northwest Forest Plan 

(USDA and USDI 1994a) and FS Land and Resource Management Plans and BLM Resource 

Management Plans as amended by the Record of Decision for Amendments to the Survey and 

Manage, Protection Buffer, and Other Mitigation Measures Standards and Guidelines, USDA 

Forest Service and USDI BLM (USDA and USDI 2001, USDA and USDI 2008 as amended by the 

2011 agreement).

ii. The proposed activities do not include those that would result in loss of suitable habitat (on 

either public or private land) for the identified ESA- listed species.

iii. The proposed activities must have wildlife biologist input/analysis to proceed.

iv. As a general rule, a disruption site is defined as approximately 100 meters radius around the 

project site. However, the unit wildlife biologist has the discretion to adjust disturbance and 

disruption distances, based on site- specific conditions.

b. Northern spotted owl

i. NSO1: To reduce adverse effects to spotted owl, projects will not generally occur during the 

critical breeding period, generally between March1 – July 15, but may vary by location (July 7 

for the Oregon North Coast Planning Province) if there is an active known owl site, predicted 

owl site (as determined through an approved modeling process), RPO (Reference Point Owl) 

and/or occupied habitat within the disruption distance of the project area. Projects should (a) 

be delayed until after the critical breeding season (unless action involves Type I helicopters, 

which extend critical nesting window to September 30); (b) delayed until it is determined that 

young are not present.

ii. NSO2: The unit wildlife biologist may extend the restricted season based on site-specific 

information (such as a late or recycle nesting attempt).

iii. NSO3: Table D-10 shows disruption distances applicable to the equipment types proposed in 

the ARBO II. These distances can be locally altered based on current information.

iv. NSO4: No activity within this BO will cause adverse effects to spotted owl critical habitat when 

analyzed against the appropriate local scale as determined by the unit wildlife biologist.

v. NSO5: For LW projects follow project design as outlined within section 22. e.

vi. NSO6: No hovering or lifting within 500 feet of the ground within occupied spotted owl habitat 

during the critical breeding season by ICS Type I or II helicopters would occur as part of any 

proposed action addressed by this assessment.

Table D-10. Disturbance, disruption (harass) and/or physical injury (harm) distance thresholds for Spotted Owls. 

Distances are to a known occupied spotted owl nest tree or suitable nest trees in unsurveyed nesting habitat.

Project Activity

No Effect 

(Mar 1 –Sept. 

30)

NLAA

“may affect” 

disturbance 

distance

(Mar 1 – Sept. 30)

LAA – Harass early 

nesting season 

disruption 

distance

(Mar 1–Jul 151)

LAA – Harass late 

nesting season 

disruption distance

(Jul 161–Sep 30)

LAA – Harm direct 

injury and/or 

mortality 

(Mar 1 – Sept. 30)

Light maintenance (e.g., 

road brushing and 

grading) at campgrounds, 

administrative facilities, 

and heavily-used roads

>0.25 mile ≤ 0.25 mile NA2 NA NA

Chainsaws (includes felling 

hazard/danger trees) >0.25 mile - 66 yards to

0.25 mile - ≤ 65 yards3 NA NA

Burning (prescribed fires, 

pile burning) >1 mile

0.25 mile to 1 

mile ≤ 0.25 mile4 NA N

A

NLAA = “not likely to adversely affect.” LAA = “likely to adversely affect” ≥ is greater than or equal to, ≤ is less than or equal to.

1. The exact dates are variable by physiographic province, and differences by locality. Work with the USFWS to select the proper dates 

when planning or implementing projects.
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2. NA = not applicable. Based on information presented in Tempel and Gutiérrez (2003, p. 700), Delaney et al. (1999, p. 69), and Kerns and 

Allwardt (1992, p. 9), we anticipate that spotted owls that select nest sites in close proximity to open roads either are undisturbed by or 

habituate to the normal range of sounds and activities associated with these roads.

3. Based on Delaney et al. (1999, p. 67) which indicates that spotted owl flush responses to above-ambient equipment sound levels and 

associated activities are most likely to occur at a distance of 65 yards (60 m) orless.

4. Based on recommendations presented in Smoke Effects to Northern Spotted Owls (USFWS 2008e, p. 4).

c. Marbled Murrelet

i. MM1: Projects will not occur within the applicable disruption and disturbance distances for 

marbled murrelets within their critical nesting period (Table D-11), unless a protocol survey 

determines marbled murrelets are not present. Otherwise the project would be LAA and either 

delayed until August 6 (with 2-hr timing restrictions) or until it is determined that young are not 

present or counted toward the limited number of LAA projects covered under this 

programmatic (with 2-hr timing restrictions).

ii. MM2: Projects within the applicable disruption and disturbance distances for marbled 

murrelets implemented between August 6 and September 15 would not begin until 2 hours 

after sunrise and would end 2 hours before sunset.

iii. MM3: No suitable, potential, or critical marbled murrelet habitat is to be removed or 

downgraded as part of this action.

iv. MM4: Garbage containing food and food trash generated by workers in project areas is secured 

or removed to minimize attraction of corvids, which have been identified as predators of 

murrelet eggs and young.

v. MM5: Table D-11 shows marbled murrelet disruption distances that are applicable to the 

proposed actions under this BO. Distances and times can be locally revised based on current 

information.

vi. MM6: For LW projects follow project design as outlined within section 22. e.

Table D-11. Disturbance, disruption (harass) and/or physical injury (harm) distance thresholds for Marbled Murrelet 

during the nesting season (April 1 to September 15). Distances are to a known occupied marbled murrelet nest tree 

or suitable nest trees in unsurveyed nesting habitat.

Action

Action not likely 

detected above 

ambient levels

ACTION LIKELY DETECTED 

BY BREEDING MURRELETS

disturbance distances

disruption 

distances

direct physical injury and/or 

mortality

Light maintenance (e.g., road 

brushing and grading) at 

campgrounds, administrative 

facilities, and heavily-used roads

> 0.25 mile ≤ 0.25 mile NA1 NA

Chainsaws (includes felling 

hazard/danger trees) >0.25 mile 111 yards to 0.25 mile ≤ 110 yards2

Potential for mortality if 

trees felled contain

platforms

Burning (prescribed fires, pile

burning) >1 mile 0.25 mile to 1 mile ≤ 0.25mile3 NA

1. NA = not applicable. We anticipate that marbled murrelets that select nest sites in close proximity to heavily used roads are either 

undisturbed by or habituate to the sounds and activities associated with these roads (Hamer and Nelson 1998, p. 21).

2. Based on recommendations from murrelet researchers that advised buffers of greater than 100 meters to reduce potential noise and 

visual disturbance to murrelets (Hamer and Nelson 1998, p. 13, USFWS 2012d, pp.6-9).

3. Based on recommendations presented in Smoke Effects to Northern Spotted Owls (USFWS 2008d, p. 4).
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Appendix E: Herbicides Formulations 

and Adjuvants

The herbicides proposed for use in Oregon are a subset of the hundreds of herbicides registered for use in the 

United States. They were chosen by the BLM nationally for maximum effectiveness against wildland weeds and 

least environmental and non-target species’ risks. Table B-2 shows the herbicides with some sample trade names, 

common plant targets, plant types it is selective for, how it is used, land types it is registered for, and typical and 

maximum rates. Table E-1, General Constraints from Herbicide Labels, supplements Table B-2, Herbicide 

Information, by listing a summary of general label constraints.

Herbicides can be categorized as selective or non-selective (see Table B-2). Selective herbicides kill only a specific 

type of plant. For example, an herbicide selective for broadleaved plants can be used to manage such species while 

maintaining desirable grass species in rangeland communities. Non-selective herbicides kill all types of plants, and 

thus must be applied only to the target species. Herbicides can be used selectively to control specific types of 

vegetation (e.g., killing a specific invasive plant species), or non-selectively in monocultures of invasive plants 

where there is no objective to retain some plants. Some herbicides are post-emergent, which means they can be 

used to kill existing vegetation; others are pre-emergent, which stops vegetation before it grows (e.g., prohibiting 

seeds from germinating) (Table B-2).

Herbicides are classified as either “general use” or “restricted use” by the EPA. Restricted use means that a 

product, or its uses, may have higher risks of adverse effects and thus can only be used by a certificated pesticide 

applicator with the appropriate training or under the direct supervision of a certified applicator (defined in 40 

C.F.R. 152.175). A license is required to purchase and apply the product and the label on the herbicide must clearly 

state that it is a “Restricted Use Pesticide.” A general use pesticide, when applied in accordance with its directions 

for use, will generally not cause unreasonable adverse effects to humans or the environment, and thus is not 

restricted to certified applicators. They can be purchased and used by the public. Picloram is the only restricted use 

herbicide analyzed in this EA.

Table E-2, Herbicide Formulations Approved for use on BLM-Administered Lands, displays the BLM National list of 

approved herbicides, which is reviewed and updated at least annually. This list identifies herbicides that are known 

to be consistent with the formulations analyzed in the Risk Assessments (see Appendix F) and otherwise suitable 

for wildland use.

Table E-3, Adjuvants Approved for Use on BLM Administered Lands, displays the adjuvants approved for use on 

BLM-administered lands nationally. This list is also reviewed at least annually. This list identifies adjuvants that are 

known to be consistent with the formulations analyzed in the Risk Assessments (see Appendix F) and are known 

not to contain R-11, POEA, petroleum, and other products prohibited by Mitigation Measures (see Appendix D), or 

that are otherwise considered unsuitable for wildland use. Table E-3 also identifies those adjuvants identified by 

the National Marine Fisheries Service and U.S. Fish and Wildlife Service in their 2013 Biological Opinion for Fish 

Habitat Restoration Activities Affecting ESA-listed Animal and Plant Species and their Designated Critical Habitat 

found in Oregon, Washington and parts of California, Idaho and Nevada (USDI 2013a, NMFS 2013) as appropriate 

for use near streams with listed fish. These adjuvants are designated under the column “ARBO II,” for the second 

programmatic Aquatic Restoration Biological Opinion.
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Table E-1. General Constraints from Herbicide Labels

Herbicides General Constraints from Labels

(follow all label requirements)

2,4-D

• Some formulations are toxic to aquatic invertebrates.

• Only use approved formulations for streamside and aquatic applications.

• Drift or runoff from terrestrial applications may adversely affect aquatic invertebrates and non-target plants.

• For terrestrial uses, do not apply directly to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not 

contaminate water when disposing of equipment washwaters.

Aminopyralid

• After grazing aminopyralid-treated forage, livestock must graze for 3 days in an untreated pasture without desirable broadleaf plants before returning to an area 

where desirable broadleaf plants are present.

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water when disposing of equipment wash-water or rinsate.

• Do not treat inside banks or bottoms of irrigation ditches, either dry or containing water, or other channels that carry water that may be used for irrigation or domestic 

purposes.

Chlorsulfuron 

• Do not apply more than 1.33 oz/acre per year in pasture, range, and Conservation Reserve Program treatments.

• Do not treat frozen soil.

• Applications to powdery, dry soil when there is low likelihood of rain soon may result in off-site damage by wind-borne soil particles.

Clopyralid

• Do not apply where soils have a rapid to very rapid permeability close to aquifers.

• Do not contaminate irrigation ditches or water used for irrigation or domestic uses.

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water when disposing of equipment wash-water.

• Avoid spray drift.

• After grazing clopyralid-treated forage, livestock must graze for 3 days in an untreated pasture without desirable broadleaf plants before returning to an area where 

desirable broadleaf plants are present.

• Do not use plant residues, including hay or straw from treated areas, or manure or bedding straw from animals that have grazed or consumed forage from treated 

areas, for composting or mulching, where susceptible plants may be grown the following season.

• Do not spread manure from animals that have grazed or consumed forage or hay from treated areas on land used for growing susceptible broadleaf crops, 

ornamentals, orchards, or other susceptible desirable plants.

Dicamba

• To prevent point source contamination, do not mix or load this pesticide within 50 feet of wells (including abandoned wells and drainage wells), sink holes, perennial 

or intermittent streams and rivers, and natural or impounded lakes and reservoirs. Do not apply this pesticide within 50 feet of wells.

• Do not apply under conditions that favor runoff. Do not apply to impervious substrates such as paved or highly compacted surfaces in areas with high potential for 

groundwater contamination. Groundwater contamination may occur in areas where soils are permeable or coarse and groundwater is near the surface.

Dicamba + 

Diflufenzopyr

• Do not load, mix, or apply within 50 feet of wells.

• Do not apply directly to water, where surface water is present, or to intertidal areas. Do not contaminate water when disposing of equipment washwaters.

• Do not apply to impervious substrates or under conditions that favor runoff. Do not apply to soils that classify as sand.

• Be cognizant of leaching where soils are permeable or where water table is shallow.

Fluridone • Do not apply in tidewater / brackish water.

Fluroxypyr

• Do not apply directly to water, to areas where surface water is present or to intertidal areas below the mean high water mark.

• Do not contaminate water when cleaning equipment or disposing of equipment washwaters.

• Do not apply where drift may be a problem due to proximity to susceptible crops or other non-target broadleaf plants.

Glyphosate • Only use approved aquatic formulations for aquatic applications.

• Do not contaminate water when cleaning equipment or disposing of equipment washwaters.
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Appendix E: Herbicide Formulations and Adjuvants

190

Herbicides General Constraints from Labels

(follow all label requirements)

• Treatment of aquatic weeds can result in oxygen depletion or loss due to decomposition of plants that can cause fish suffocation.

• This is a non-selective herbicide.

• Avoid drift.

Hexazinone

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark. Do not contaminate water when 

disposing of equipment wash-water.

• Use care where soils are permeable to avoid groundwater contamination.

• Will kill grasses.

Imazapic 

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water when disposing of equipment wash-water.

• To reduce run-off, avoid applications when rain is forecast w/in 48 hours.

Imazapyr

• Aquatic applications (with approved products) can only be made within the restrictions outlined on the label.

• Otherwise, do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water when disposing of equipment wash-water.

Metsulfuron methyl

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water when disposing of equipment wash-water.

• This herbicide is injurious to plants at extremely low concentrations. Non-target plants may be adversely affected from drift and run-off.

Picloram

• Do not use manure from animals grazing treated areas or feeding on treated hay on land used for growing broadleaf crops, ornamentals, orchards or other 

susceptible, desirable plants. Manure may contain enough picloram to cause injury to susceptible plants.

• Do not use grass or hay from treated areas for composting or mulching of susceptible broadleaf plants or crops.

• Do not transfer livestock from treated grazing areas (or feeding of treated hay) onto sensitive broadleaf crop areas without first allowing 7 days of grazing on an 

untreated grass pasture (or feeding of untreated hay). Otherwise, urine and manure may contain enough picloram to cause injury to sensitive broadleaf plants.

• Restricted use. May injure susceptible, non-target plants. This herbicide is injurious to plants at extremely low concentrations. Non-target plants may be adversely 

affected from drift and run-off.

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not make application when circumstances favor movement from treatment site. Do not contaminate water or water sources when mixing, loading, or disposing of 

equipment wash-water.

• May leach thru soil and contaminate groundwater where soils are permeable, particularly where water table is shallow.

• Do not apply within the root zone of desirable trees unless such injury can be tolerated.

Rimsulfuron

• Do not graze treated sites or cut for forage or hay for a minimum of 1 year after application in order to allow newly emerged grasses sufficient time to become 

established.

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Do not contaminate water by cleaning of equipment or disposal of equipment washwaters or rinsate.

• Rainfall or irrigation is needed for herbicide activation.

Sulfometuron 

methyl 

• Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark. Do not contaminate water when 

disposing of equipment wash-water.

• Applications to powdery, dry soil when there is low likelihood of rain soon may result in off-site damage by wind-borne soil particles.

• Do not treat frozen soil.

• Do not apply in or on irrigation ditches or canals, including their outer banks.
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix E: Herbicide Formulations and Adjuvants

191

Herbicides General Constraints from Labels

(follow all label requirements)

Triclopyr

• Treatment of aquatic weeds can result in oxygen depletion or loss due to decomposition of plants in certain situations, which can cause fish suffocation.

• Certain approved products can be used in and around standing water sites. Minimize overspray to open water (streams, lakes, etc.) when treating vegetation growing 

at water edge. Do not contaminate water when disposing of equipment wash-water.

Herbicides analyzed for Research and Demonstration

Fluazifop-P-butyl

• This product is toxic to fish and aquatic invertebrates. Do not apply to areas where runoff into water bodies is expected.

• Do not apply when weather conditions favor drift from target areas.

• Do not apply directly to water, to areas where surface water is present, or to intertidal areas below the mean high water mark.

• Fluazifop-P-butyl is known to leach through soil into groundwater under certain conditions as a result of label use. This chemical may leach into groundwater if used in 

areas where soils are permeable, particularly where the water table is shallow.

• This product may impact surface water quality due to runoff of rain water. This is especially true for poorly draining soils and soils with shallow groundwater.

• This product is classified as having high potential for reaching surface water via runoff for several months or more after application. A level, welI-maintained vegetative 

buffer strip between areas to which this product is applied and surface water features such as ponds, streams, and springs will reduce the potential loading of 

fluazifop-P-butyl from runoff water and sediment. Runoff of this product will be reduced by avoiding applications when rainfall is forecasted to occur within 48 hours.

• Do not treat areas while unprotected humans or domestic animals are present in the treatment areas. Do not allow entry into treated areas without protective 

clothing until sprays have dried.

• Do not apply if rainfall is expected within 1 hour.

• Do not use flood type or other spray nozzle tips that deliver coarse, large droplet sprays.

Sethoxydim

• Avoid all direct or indirect contract with any desired grass crop (e.g. corn, rice, small grains, sorghum, and ornamental grasses and turfgrass).

• Do not apply to grass weeds or crops under stress because of lack of moisture, hail damage, flooding, herbicide injury, or widely fluctuating temperatures. 

Unsatisfactory control may result. In irrigated areas, it may be necessary to irrigate before application to ensure active grass weed growth.

• A minimum of 14 days is required between sequential applications.

• Do not use selective application equipment such as recirculating sprayers, wiper applicators or shielded applicators.

• Do not apply through any type of irrigation equipment.

• Is rainfast 1 hour after application. 
Integrated Invasive Plant Management for the Northwest Oregon District

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Appendix E: Herbicide Formulations and Adjuvants

192

Table E-2. Herbicide Formulations Approved for Use on BLM-Administered Lands1

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

2,4-D 2,4-D 4# Amine Weed Killer UAP-Platte Chem. Co. 34704-120

2,4-D 2,4-D Amine Helena Chemical Company 5905-72

2,4-D 2,4-D Amine Setre (Helena) 5905-72

2,4-D 2,4-D Amine 4 Albaugh, Inc./Agri Star 42750-19

2,4-D 2,4-D Amine 4 Helena Chemical Company 42750-19-5905

2,4-D 2,4-D LV 4 Albaugh, Inc./Agri Star 42750-15

2,4-D 2,4-D LV4 Setre (Helena) 5905-90

2,4-D 2,4-D LV 6 Albaugh, Inc./Agri Star 42750-20

2,4-D 2,4-D LV6 Helena Chemical Company 4275-20-5905

2,4-D 2,4-D LV6 Setre (Helena) 5905-93

2,4-D 2,4-D LV 6 Ester Nufarm Americas Inc. 228-95

2,4-D Agrisolution 2,4-D Amine 4 Agriliance, LLC 1381-103

2,4-D Agrisolution 2,4-D Amine 4 Winflied Solutions, LLC 1381-103

2,4-D Agrisolution 2,4-D LV4 Agriliance, LLC 1381-102

2,4-D Agrisolution 2,4-D LV4 Winflied Solutions, LLC 1381-102

2,4-D Agrisolution 2,4-D LV6 Agriliance, LLC 1381-101

2,4-D Agrisolution 2,4-D LV6 Winflied Solutions, LLC 1381-101

2,4-D Alligare 2,4-D Amine Alligare, LLC 81927-38

2,4-D Alligare 2,4-D LV 6 Alligare, LLC 81927-39

2,4-D Amine 4 Wilbur-Ellis Co. 2935-512

2,4-D Aqua-Kleen Nufarm Americas Inc. 228-378

2,4-D Aqua-Kleen Nufarm Americas Inc. 71368-4

2,4-D Barrage HF Helena Chemical Company 5905-529

2,4-D Barrage LV Ester Setre (Helena) 5905-504

2,4-D Base Camp Amine 4 Wilbur-Ellis Co. 71368-1-2935

2,4-D Base Camp LV6 Wilbur-Ellis Co. 2935-553

2,4-D Broadrange 55 Wilbur-Ellis Co. 2217-813-2935

2,4-D Clean Amine Loveland Products, Inc. 34704-120

2,4-D Clean Crop Amine 4 UAP-Platte Chem. Co. 34704-5 CA

2,4-D Clean Crop Low Vol 6 Ester UAP-Platte Chem. Co. 34704-125

2,4-D Clean Crop LV-4 ES UAP-Platte Chem. Co. 34704-124

2,4-D Cornbelt 4 lb. Amine Van Diest Supply Co. 11773-2

2,4-D Cornbelt 4# LoVol Ester Van Diest Supply Co. 11773-3

2,4-D Cornbelt 6# LoVol Ester Van Diest Supply Co. 11773-4

2,4-D D-638 Albaugh, Inc./Agri Star 42750-36

2,4-D De-Amine 4 Drexel Chemical Company 19713-650

2,4-D De-Amine 6 Drexel Chemical Company 19713-651

2,4-D De-Ester LV4 Drexel Chemical Company 19713-345

2,4-D De-Ester LV6 Drexel Chemical Company 19713-655

2,4-D Esteron 99C Nufarm Americas Inc. 62719-9-71368

2,4-D Five Star Albaugh, Inc./Agri Star 42750-49

2,4-D Formula 40 Nufarm Americas Inc. 228-357

2,4-D HardBall Helena Chemical Company 5905-549

2,4-D Hi-Dep PBI/Gordon Corporation 2217-703

2,4-D Lo Vol-4 Wilbur-Ellis Co. 228-139-2935

2,4-D Low Vol 4 Ester Weed Killer Loveland Products, Inc. 34704-124

2,4-D Lo Vol-6 Ester Wilbur-Ellis Co. 228-95-2935

2,4-D Low Vol 6 Ester Weed Killer Loveland Products, Inc. 34704-125

2,4-D Opti-Amine Helena Chemical Company 5905-501

2,4-D Phenoxy 088 Winfield Solutions, LLC 42750-36-9779

2,4-D Platoon Nufarm Americas Inc. 228-145

2,4-D Rugged Winfield Solutions, LLC 1381-247
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193

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

2,4-D Saber Loveland Products, Inc. 34704-803

2,4-D Salvo Loveland Products, Inc. 34704-609

2,4-D Salvo LV Ester UAP-Platte Chem. Co. 34704-609

2,4-D Savage DS Loveland Products, Inc. 34704-606

2,4-D Savage DS UAP-Platte Chem. Co. 34704-606

2,4-D Shredder 2,4-D LV4 Winfield Solutions, LLC 1381-102

2,4-D Shredder Amine 4 Winfield Solutions, LLC 1381-103

2,4-D Shredder E-99 Winfield Solutions, LLC 1381-195

2,4-D Solution Water Soluble Nufarm Americas Inc. 228-260

2,4-D Solve 2,4-D Albaugh, Inc./Agri Star 42750-22

2,4-D Unison Helena Chemical Company 5905-542

2,4-D Weedar 64 Nufarm Americas Inc. 71368-1

2,4-D WEEDestroy AM-40 Nufarm Americas Inc. 228-145

2,4-D Weedone LV-4 Nufarm Americas Inc. 228-139-71368

2,4-D Weedone LV-4 Solventless Nufarm Americas Inc. 71368-14

2,4-D Weedone LV-6 Nufarm Americas Inc. 71368-11

2,4-D Whiteout 2,4-D Loveland Products, Inc. 34704-1032

Aminopyralid Milestone Dow AgroSciences 62719-519

Aminopyralid + Metsulfuron 

Methyl Chaparral Dow AgroSciences 62719-597

Aminopyralid + Metsulfuron 

Methyl Opensight Dow AgroSciences 62719-597

Chlorsulfuron Alligare Chlorsulfuron Alligare, LLC 81927-43

Chlorsulfuron Chlorsulfuron 75 Alligare, LLC 81927-43

Chlorsulfuron Chlorsulfuron E-Pro 75 WDG Nufarm Americas Inc. 79676-72

Chlorsulfuron Nufarm Chlorsulf SPC 75 WDG 

Herbicide Nufarm Americas Inc. 228-672

Chlorsulfuron Telar DF DuPont Crop Protection 352-522

Chlorsulfuron Telar XP Bayer Environmental Science 432-1561

Chlorsulfuron Telar XP DuPont Crop Protection 352-654

Clopyralid CleanSlate Nufarm Americas Inc. 228-491

Clopyralid Clopyralid 3 Alligare, LLC 42750-94-81927

Clopyralid Clopyralid 3 Alligare, LLC 81927-14

Clopyralid Pyramid R&P Albaugh, Inc. 42750-94

Clopyralid Reclaim Dow AgroSciences 62719-83

Clopyralid Spur Albaugh, Inc. 42750-89

Clopyralid Stinger Dow AgroSciences 62719-73

Clopyralid Transline Dow AgroSciences 62719-259

Clopyralid + 2,4-D Cody Herbicide Alligare, LLC 81927-28

Clopyralid + 2,4-D Commando Albaugh, Inc. 42750-92

Clopyralid + 2,4-D Curtail Dow AgroSciences 62719-48

Clopyralid + 2,4-D Cutback Nufarm Americas Inc. 71368-72

Dicamba Banvel Arysta LifeScience N.A. Corp. 66330-276

Dicamba Banvel Micro Flo Company 51036-289

Dicamba Clarity BASF Corporation 7969-137

Dicamba Cruise Control Alligare, LLC 42750-40-81927

Dicamba Diablo Nufarm Americas Inc. 228-379

Dicamba Dicamba DMA Albaugh, Inc./Agri Star 42750-40

Dicamba Kam-Ba Drexel Chemical Company 19713-624

Dicamba Rifle Loveland Products, Inc. 34704-861

Dicamba Sterling Blue Winfield Solutions, LLC 7969-137-1381

Dicamba Vanquish Syngenta Professional Products 100-884

Dicamba Vanquish Herbicide Nufarm Americas Inc. 228-397
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Appendix E: Herbicide Formulations and Adjuvants

194

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

Dicamba Vision Albaugh, Inc. 42750-98

Dicamba Vision Helena Chemical Company 5905-576

Dicamba + 2,4-D Brash Winfield Solutions, LLC 1381-202

Dicamba + 2,4-D Brush-Rhap Helena Chemical Company 5905-568

Dicamba + 2,4-D Dicamba + 2,4-D DMA Alligare, LLC 81927-42

Dicamba + 2,4-D KambaMaster Nufarm Americas Inc. 71368-34

Dicamba + 2,4-D Latigo Helena Chemical Company 5905-564

Dicamba + 2,4-D Outlaw Helena Chemical Company 5905-574

Dicamba + 2,4-D Range Star Albaugh, Inc./Agri Star 42750-55

Dicamba + 2,4-D Rifle-D Loveland Products, Inc. 34704-869

Dicamba + 2,4-D Weedmaster BASF Ag. Products 7969-133

Dicamba + 2,4-D Weedmaster Nufarm Americas Inc. 71368-34

Dicamba + 2,4-D Veteran 720 Nufarm Americas Inc. 228-295

Dicamba + Diflufenzopyr Distinct BASF Corporation 7969-150

Dicamba + Diflufenzopyr Overdrive BASF Corporation 7969-150

Fluridone Alligare Fluridone Albaugh, LLC 81927-45

Fluridone Avast! SePRO Corporation 67690-30

Fluridone Fluridone 4L Albaugh, LLC 42750-280

Fluridone Sonar AS SePRO Corporation 67690-4

Fluridone Sonar Precision Release SePRO Corporation 67690-12

Fluridone Sonar Q SePRO Corporation 67690-3

Fluridone Sonar SRP SePRO Corporation 67690-3

Fluroxypyr Alligare Fluroxypyr Alligare, LLC 66330-385-81927

Fluroxypyr Comet Selective Nufarm Americas Inc. 71368-87

Fluroxypyr Vista XRT Dow AgroSciences 62719-586

Glyphosate Accord Concentrate Dow AgroSciences 62719-324

Glyphosate Accord SP Dow AgroSciences 62719-322

Glyphosate Accord XRT Dow AgroSciences 62719-517

Glyphosate Accord XRT II Dow AgroSciences 62719-556

Glyphosate Agrisolutions Cornerstone Winfield Solutions, LLC 1381-191

Glyphosate Agrisolutions Cornerstone 5 Plus Winfield Solutions, LLC 1381-241

Glyphosate Agrisolutions Cornerstone Plus Winfield Solutions, LLC 1381-192

Glyphosate Agrisolutions Rascal Winfield Solutions, LLC 1381-191

Glyphosate Agrisolutions Rascal Plus Winfield Solutions, LLC 1381-192

Glyphosate Aqua Neat Nufarm Americas Inc. 228-365

Glyphosate Aqua Star Albaugh, Inc./Agri Star 42750-59

Glyphosate Aquamaster Monsanto 524-343

Glyphosate AquaPro Aquatic Herbicide SePRO Corporation 62719-324-67690

Glyphosate Buccaneer Tenkoz 55467-10

Glyphosate Buccaneer Plus Tenkoz 55467-9

Glyphosate ClearOut 41 Plus Chem. Prod. Tech., LLC 70829-3

Glyphosate Credit Xtreme Nufarm Americas Inc. 71368-81

Glyphosate Foresters Nufarm Americas Inc. 228-381

Glyphosate Forest Star Albaugh, Inc./Agri Star 42570-61

Glyphosate Four Power Plus Loveland Products, Inc. 34704-890

Glyphosate Gly Star Gold Albaugh, Inc./Agri Star 42750-61

Glyphosate Gly Star Original Albaugh, Inc./Agri Star 42750-60

Glyphosate Gly Star Plus Albaugh, Inc./Agri Star 42750-61

Glyphosate Gly Star Pro Albaugh, Inc./Agri Star 42750-61

Glyphosate Gly-4 Universal Crop Protection 

Alliance, LLC 42750-60-72693

Glyphosate Gly-4 Plus Universal Crop Protection 

Alliance, LLC 72693-1
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Appendix E: Herbicide Formulations and Adjuvants

195

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

Glyphosate Gly-4 Plus Universal Crop Protection 

Alliance, LLC 42750-61-72693

Glyphosate Glyfos Cheminova 4787-31

Glyphosate Glyfos Aquatic Cheminova 4787-34

Glyphosate Glyfos PRO Cheminova 67760-57

Glyphosate GlyphoMate 41 PBI/Gordon Corporation 2217-847

Glyphosate Glyphosate 4 Vegetation Man., LLC 73220-6-74477

Glyphosate Glyphosate 4 + Alligare, LLC 81927-9

Glyphosate Glyphosate 4 PLUS Alligare, LLC 81927-9

Glyphosate Glyphosate 5.4 Alligare, LLC 81927-8

Glyphosate Glypro Dow AgroSciences 62719-324

Glyphosate Glypro Plus Dow AgroSciences 62719-322

Glyphosate Honcho Monsanto 524-445

Glyphosate Honcho Plus Monsanto 524-454

Glyphosate Imitator 25% Concentration Drexel Chemical Company 19713-628

Glyphosate Imitator Aquatic Drexel Chemical Company 19713-623

Glyphosate Imitator DA Drexel Chemical Company 19713-586

Glyphosate Imitator Plus Drexel Chemical Company 19713-526

Glyphosate Imitator RTU Drexel Chemical Company 19713-607

Glyphosate KleenUp Pro Loveland Products, Inc. 34704-890

Glyphosate Mad Dog Plus Loveland Products, Inc. 34704-890

Glyphosate Makaze Loveland Products, Inc. 34704-890

Glyphosate Mirage Loveland Products, Inc. 34704-889

Glyphosate Mirage Herbicide UAP-Platte Chem. Co. 524-445-34704

Glyphosate Mirage Plus Loveland Products, Inc. 34704-890

Glyphosate Mirage Plus Herbicide UAP-Platte Chem. Co. 524-454-34704

Glyphosate Rattler Setre (Helena) 524-445-5905

Glyphosate Razor Nufarm Americas Inc. 228-366

Glyphosate Razor Pro Nufarm Americas Inc. 228-366

Glyphosate Rodeo Dow AgroSciences 62719-324

Glyphosate Roundup Custom Monsanto 524-343

Glyphosate Roundup Original Monsanto 524-445

Glyphosate Roundup Original II Monsanto 524-454

Glyphosate Roundup Original II CA Monsanto 524-475

Glyphosate Roundup PRO Monsanto 524-475

Glyphosate Roundup PRO Concentrate Monsanto 524-529

Glyphosate Roundup PRO Dry Monsanto 524-505

Glyphosate Roundup PROMAX Monsanto 524-579

Glyphosate Showdown Helena Chemical Company 71368-25-5905

Glyphosate + 2,4-D Campaign Monsanto 524-351

Glyphosate + 2,4-D Imitator Plus D Drexel Chemical Company 19713-635

Glyphosate + 2,4-D Landmaster BW Albaugh, Inc./Agri Star 42570-62

Glyphosate + 2,4-D Landmaster BW Monsanto 524-351

Hexazinone Pronone 10G Pro-Serve 33560-21

Hexazinone Pronone 25G Pro-Serve 33560-45

Hexazinone Pronone MG Pro-Serve 33560-21

Hexazinone Pronone Power Pellet Pro-Serve 33560-41

Hexazinone Velossa Helena Chemical Company 5905-579

Hexazinone Velpar DF DuPont Crop Protection 352-581

Hexazinone Velpar DF VU Bayer Environmental Science 432-1576

Hexazinone Velpar L DuPont Crop Protection 352-392

Hexazinone Velpar L VU Bayer Environmental Science 432-1573

Hexazinone Velpar ULW DuPont Crop Protection 352-450
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Appendix E: Herbicide Formulations and Adjuvants

196

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

Hexazinone + Sulfometuron 

methyl Oustar Bayer Environmental Science 432-1553

Hexazinone + Sulfometuron 

methyl Oustar DuPont Crop Protection 352-603

Hexazinone + Sulfometuron 

methyl Westar Bayer Environmental Science 432-1558

Hexazinone + Sulfometuron 

methyl Westar DuPont Crop Protection 352-626

Imazapic Nufarm Imazapic 2SL Nufarm Americas Inc. 71368-99

Imazapic Panoramic 2SL Alligare, LLC 66222-141-81927

Imazapic Plateau BASF 241-365

Imazapic + Glyphosate Journey BASF 241-417

Imazapyr Arsenal BASF 241-346

Imazapyr Arsenal Applicators Conc. BASF 241-299

Imazapyr Arsenal PowerLine BASF 241-431

Imazapyr Arsenal Railroad Herbicide BASF 241-273

Imazapyr Chopper BASF 241-296

Imazapyr Ecomazapyr 2SL Alligare, LLC 81927-22

Imazapyr Ecomazapyr 2 SL Vegetation Man., LLC 74477-6

Imazapyr Habitat BASF 241-426

Imazapyr Habitat Herbicide SePRO Corporation 241-426-67690

Imazapyr Imazapyr 2 SL Vegetation Man., LLC 74477-4

Imazapyr Imazapyr 2SL Alligare, LLC 81927-23

Imazapyr Imazapyr 4 SL Vegetation Man., LLC 74477-5

Imazapyr Imazapyr 4SL Alligare, LLC 81927-24

Imazapyr Polaris Nufarm Americas Inc. 228-534

Imazapyr Polaris AC Nufarm Americas Inc. 241-299-228

Imazapyr Polaris AC Nufarm Americas Inc. 228-480

Imazapyr Polaris AC Complete Nufarm Americas Inc. 228-570

Imazapyr Polaris AQ Nufarm Americas Inc. 241-426-228

Imazapyr Polaris Herbicide Nufarm Americas Inc. 241-346-228

Imazapyr Polaris RR Nufarm Americas Inc. 241-273-228

Imazapyr Polaris SP Nufarm Americas Inc. 228-536

Imazapyr Polaris SP Nufarm Americas Inc. 241-296-228

Imazapyr Rotary 2 SL Alligare, LLC 81927-6

Imazapyr SSI Maxim Arsenal 0.5G SSI Maxim Co., Inc. 34913-23

Imazapyr SSI Maxim Arsenal 5.0G SSI Maxim Co., Inc. 34913-24

Imazapyr Stalker BASF 241-398

Metsulfuron methyl AmTide MSM 60DF Herbicide AmTide, LLC 83851-3

Metsulfuron methyl Escort DF DuPont Crop Protection 352-439

Metsulfuron methyl Escort XP Bayer Environmental Science 432-1549

Metsulfuron methyl Escort XP DuPont Crop Protection 352-439

Metsulfuron methyl Metsulfuron Methyl DF Vegetation Man., LLC 74477-2

Metsulfuron methyl MSM 60 Alligare, LLC 81927-7

Metsulfuron methyl MSM E-AG 60 EG Herbicide Etigra, LLC 81959-14

Metsulfuron methyl MSM E-Pro 60 EG Herbicide Etigra, LLC 81959-14

Metsulfuron methyl Patriot Nufarm Americas Inc. 228-391

Metsulfuron methyl PureStand Nufarm Americas Inc. 71368-38

Picloram Grazon PC Dow AgroSciences 62719-181

Picloram OutPost 22K Dow AgroSciences 62719-6

Picloram Picloram 22K Alligare, LLC 81927-18

Picloram Picloram K Alligare, LLC 81927-17

Picloram Tordon 22K Dow AgroSciences 62719-6
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Appendix E: Herbicide Formulations and Adjuvants

197

Active Ingredient Trade Name Manufacturer EPA Registration 

Number

Picloram Tordon K Dow AgroSciences 62719-17

Picloram Triumph 22K Albaugh, Inc. 42750-79

Picloram Triumph K Albaugh, Inc. 42750-81

Picloram Trooper 22K Nufarm Americas Inc. 228-535

Rimsulfuron Laramie 25DF Alligare, LLC 81927-57

Rimsulfuron Matrix SG Dupont Crop Protection 352-768

Sulfometuron methyl Oust DF DuPont Crop Protection 352-401

Sulfometuron methyl Oust XP Bayer Environmenatl Science 432-1552

Sulfometuron methyl Oust XP DuPont Crop Protection 352-601

Sulfometuron methyl SFM 75 Alligare, LLC 81927-26

Sulfometuron methyl SFM 75 Vegetation Man., LLC 72167-11-74477

Sulfometuron methyl SFM E-Pro 75EG Etigra, LLC 79676-16

Sulfometuron methyl Spyder Nufarm Americas Inc. 228-408

Triclopyr Boulder 6.3 Alligare, LLC 81927-54

Triclopyr Ecotriclopyr 3 SL Vegetation Man., LLC 72167-49-74477

Triclopyr Element 3A Dow AgroSciences 62719-37

Triclopyr Element 4 Dow AgroSciences 62719-40

Triclopyr Forestry Garlon XRT Dow AgroSciences 62719-553

Triclopyr Garlon 3A Dow AgroSciences 62719-37

Triclopyr Garlon 4 Dow AgroSciences 62719-40

Triclopyr Garlon 4 Ultra Dow AgroSciences 62719-527

Triclopyr Pathfinder II Dow AgroSciences 62719-176

Triclopyr Relegate Nufarm Americas Inc. 228-521

Triclopyr Relegate RTU Nufarm Americas Inc. 228-522

Triclopyr Remedy Dow AgroSciences 62719-70

Triclopyr Remedy Ultra Dow AgroSciences 62719-552

Triclopyr Renovate 3 SePRO Corporation 62719-37-67690

Triclopyr Renovate OTF SePRO Corporation 67690-42

Triclopyr Tahoe 3A Nufarm Americas Inc. 228-384

Triclopyr Tahoe 3A Nufarm Americas Inc. 228-518

Triclopyr Tahoe 3A Nufarm Americas Inc. 228-520

Triclopyr Tahoe 4E Nufarm Americas Inc. 228-385

Triclopyr Tahoe 4E Herbicide Nufarm Americas Inc. 228-517

Triclopyr Triclopry 4 Alligare, LLC 81927-11

Triclopyr Triclopyr 3 Alligare, LLC 81927-13

Triclopyr Triclopyr 3 SL Vegetation Man., LLC 72167-53-74477

Triclopyr Triclopyr RTU Albaugh, LLC 42750-173

Triclopyr Triclopyr RTU Alligare, LLC 81927-33

Triclopyr Trycera Helena Chemical Company 5905-580

Triclopyr Vastlan Dow AgroSciences 62719-687

1. Approved list as of January 6, 2017.

Table E-3. Adjuvants Approved for Use on BLM Administered Lands1

Adjuvant Type Trade Name Manufacturer ARBO2

Surfactants 

Non-ionic Surfactant 90-10 Surfactant Brewer International

Non-ionic Surfactant A-90 Alligare, LLC

Non-ionic Surfactant Activate Plus Winfield Solutions, LLC

Non-ionic Surfactant Activator 90 Loveland Products, Inc.

Non-ionic Surfactant Ad Spray 90 Helena Chemical Company

Non-ionic Surfactant Alligare Surface Alligare, LLC

Non-ionic Surfactant Alligare Surface West Alligare, LLC

Non-ionic Surfactant Alligare Trace Alligare, LLC
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Adjuvant Type Trade Name Manufacturer ARBO2

Non-ionic Surfactant Aquafact Crop Production Services

Non-ionic Surfactant Aqufact Aqumix, Inc.

Non-ionic Surfactant Audible 80 Exacto, Inc.

Non-ionic Surfactant Audible 90 Exacto, Inc.

Non-ionic Surfactant Brewer 90-10 Brewer International

Non-ionic Surfactant Chempro S-820 Chemorse Ltd.

Non-ionic Surfactant Chempro S-910 Chemorse Ltd.

Non-ionic Surfactant Chemsurf 80 Chemorse Ltd.

Non-ionic Surfactant Chemsurf 90 Chemorse Ltd.

Non-ionic Surfactant Cornbelt Premier 90 Van Diest Supply Co.

Non-ionic Surfactant Cornbelt Trophy Gold Van Diest Supply Co.

Non-ionic Surfactant Denali-EA Wilbur-Ellis Co.

Non-ionic Surfactant Elite Platinum Red River Specialties, Inc.

Non-ionic Surfactant EP-90 Eco-Pak, LLC

Non-ionic Surfactant Haf-Pynt Drexel Chemical Company

Non-ionic Surfactant Hum-AC 820 Drexel Chemical Company

Non-ionic Surfactant Induce Setre (Helena)

Non-ionic Surfactant Induce Helena Chemical Company

Non-ionic Surfactant Induce pH Helena Chemical Company

Non-ionic Surfactant Inlet Helena Chemical Company

Non-ionic Surfactant LI-700 Loveland Products, Inc. 

Non-ionic Surfactant Magnify Monterey AgResources 

Non-ionic Surfactant NIS 90:10 Precision Laboratories, LLC

Non-ionic Surfactant NIS-EA Wilbur-Ellis Co.

Non-ionic Surfactant No Foam A Creative Marketing & Research, Inc.

Non-ionic Surfactant Optima Helena Chemical Company

Non-ionic Surfactant PAS-800 Drexel Chemical Company

Non-ionic Surfactant Preference Winfield Solutions, LLC

Non-ionic Surfactant R-900 Wilbur-Ellis Co.

Non-ionic Surfactant Rainer-EA Wilbur-Ellis Co.

Non-ionic Surfactant Range Master ORO Agri Inc.

Non-ionic Surfactant Red River 90 Red River Specialties, Inc.

Non-ionic Surfactant Red River NIS Red River Specialties, Inc.

Non-ionic Surfactant Scanner Loveland Products, Inc.

Non-ionic Surfactant Spec 90/10 Helena Chemical Company

Non-ionic Surfactant Spray Activator 85 Van Diest Supply Co.

Non-ionic Surfactant Spreader 90 Loveland Products, Inc.

Non-ionic Surfactant Spret Helena Chemical Company

Non-ionic Surfactant Super Spread 90 Wilbur-Ellis Co.

Non-ionic Surfactant Super Spread 7000 Wilbur-Ellis Co.

Non-ionic Surfactant Surf-Ac 910 Drexel Chemical Company

Non-ionic Surfactant Surf-Ac 820 Drexel Chemical Company

Non-ionic Surfactant UAP Surfactant 80/20 Loveland Products, Inc.

Non-ionic Surfactant Wetcit ORO Agri Inc.

Non-ionic Surfactant X-77 Loveland Products, Inc.

Spreader/Sticker Agri-Trend Spreader Agri-Trend

Spreader/Sticker Attach Loveland Products, Inc.

Spreader/Sticker Aqua-King Plus Winfield Solutions, LLC

Spreader/Sticker Bond Loveland Products, Inc. 

Spreader/Sticker Bond Max Loveland Products, Inc.

Spreader/Sticker Chempro S-196 Chemorse Ltd.

Spreader/Sticker Cohere Helena Chemical Company

Spreader/Sticker CWC 90 CWC Chemical, Inc.

Spreader/Sticker Gulfstream Winfield Solutions, LLC
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Adjuvant Type Trade Name Manufacturer ARBO2

Spreader/Sticker Insist 90 Wilbur-Ellis Co.

Spreader/Sticker Lastick Setre (Helena)

Spreader/Sticker Nu-Film-IR Miller Chem. & Fert. Corp.

Spreader/Sticker Nu Film 17 Miller Chem. & Fert. Corp.

Spreader/Sticker Nu Film P Miller Chem. & Fert. Corp.

Spreader/Sticker Onside Kick Exacto, Inc.

Spreader/Sticker Pinene II Drexel Chemical Company

Spreader/Sticker Protyx Precision Laboratories, LLC

Spreader/Sticker R-56 Wilbur-Ellis Co.

Spreader/Sticker Rocket DL Monterey AgResources

Spreader/Sticker Tactic Loveland Products, Inc. 

Spreader/Sticker TopFilm Biosorb, Inc.

Spreader/Sticker Widespread? Max Loveland Products, Inc.

Silicone-based Aero Dyne-Amic Helena Chemical Company

Silicone-based Aircover Winfield Solutions, LLC

Silicone-based Alligare OSS/NIS Alligare, LLC

Silicone-based Chempro S-172 Chemorse Ltd.

Silicone-based Dyne-Amic Helena Chemical Company 

Silicone-based Elite Marvel Red River Specialties, Inc.

Silicone-based Freeway Loveland Products, Inc.

Silicone-based Kinetic Setre (Helena) 

Silicone-based Phase Loveland Products, Inc.

Silicone-based Phase II Loveland Products, Inc.

Silicone-based Scrimmage Exacto, Inc.

Silicone-based SilEnergy Brewer International

Silicone-based Sil-Fact Drexel Chemical Company

Silicone-based Sil-MES 100 Drexel Chemical Company

Silicone-based Silnet 200 Brewer International

Silicone-based Silwet L-77 Loveland Products, Inc.

Silicone-based Speed Precision Laboratories, LLC

Silicone-based Sun Spreader Red River Specialties, Inc.

Silicone-based Syl-coat Wilbur-Ellis Co.

Silicone-based Sylgard 309 Wilbur-Ellis Co.

Silicone-based Syl-Tac Wilbur-Ellis Co.

Oil-based 

Crop Oil Concentrate 60/40 Crop Oil Concentrate Chemorse Ltd.

Crop Oil Concentrate Agri-Dex Helena Chemical Company 

Crop Oil Concentrate Alligare Forestry Oil Alligare, LLC

Crop Oil Concentrate Brewer 83-17 Brewer International

Crop Oil Concentrate Cornbelt Crop Oil Concentrate Van Diest Supply Co.

Crop Oil Concentrate Cornbelt Premium Crop Oil Concentrate Van Diest Supply Co.

Crop Oil Concentrate Crop Oil Concentrate Helena Chemical Company

Crop Oil Concentrate Crop Oil Concentrate Loveland Products, Inc.

Crop Oil Concentrate CWR Herbicide Activator Creative Marketing & Research, Inc.

Crop Oil Concentrate Exchange Precision Laboratories, LLC

Crop Oil Concentrate Herbimax Loveland Products, Inc.

Crop Oil Concentrate Maximizer Crop Oil Conc. Loveland Products, Inc.

Crop Oil Concentrate Monterey M.S.O. Monterey AgResources

Crop Oil Concentrate Mor-Act Wilbur-Ellis Co.

Crop Oil Concentrate Peptoil Drexel Chemical Company

Crop Oil Concentrate Power-Line Crop Oil Land View Inc.

Crop Oil Concentrate Primary Drexel Chemical Company

Crop Oil Concentrate Prime Oil Winfield Solutions, LLC

Crop Oil Concentrate R.O.C. Rigo Oil Conc. Wilbur-Ellis Co.
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Adjuvant Type Trade Name Manufacturer ARBO2

Crop Oil Concentrate Red River Forestry Oil Red River Specialties, Inc.

Crop Oil Concentrate Red River Pacer Crop Oil Red River Specialties, Inc.

Crop Oil Concentrate Superb HC Winfield Solutions, LLC 

Methylated Seed Oil 60/40 MSO Chemorse Ltd.

Methylated Seed Oil Alligare MSO Alligare, LLC

Methylated Seed Oil Alligare MSO West Alligare, LLC

Methylated Seed Oil Atmos Winfield Solutions, LLC

Methylated Seed Oil Conquer Chemorse Ltd.

Methylated Seed Oil Cornbelt Base Van Diest Supply Co.

Methylated Seed Oil Cornbelt Methylates Soy-Stik Van Diest Supply Co.

Methylated Seed Oil Destiny HC Winfield Solutions, LLC 

Methylated Seed Oil Elite Supreme Red River Specialties, Inc.

Methylated Seed Oil Hasten Wilbur-Ellis Co.

Methylated Seed Oil Hasten-EA Wilbur-Ellis Co.

Methylated Seed Oil Hot MES Drexel Chemical Company

Methylated Seed Oil Kixyt Precision Laboratories, LLC.

Methylated Seed Oil MES-100 Drexel Chemical Company

Methylated Seed Oil Methylated Spray Oil Conc. Helena Chemical Company

Methylated Seed Oil Monterey M.S.O. Monterey AgResources

Methylated Seed Oil MSO Concentrate Alligare, LLC

Methylated Seed Oil MSO Concentrate Loveland Products, Inc.

Methylated Seed Oil Premium MSO Helena Chemical Company

Methylated Seed Oil Persist Ultra Precision Laboratories, LLC.

Methylated Seed Oil Red River Supreme Red River Specialties, Inc.

Methylated Seed Oil Renegade 2.0 Wilbur-Ellis Co.

Methylated Seed Oil Renegade-EA Wilbur-Ellis Co.

Methylated Seed Oil Sunburn Red River Specialties, Inc.

Methylated Seed Oil SunEnergy Brewer International

Methylated Seed Oil Sunset Red River Specialties, Inc.

Methylated Seed Oil Sun Wet Brewer International

Methylated Seed Oil Super Kix Wilbur-Ellis Co.

Methylated Seed Oil Super Spread MSO Wilbur-Ellis Co.

Methylated Seed Oil + Organosilicone Alligare MVO Plus Alligare, LLC

Methylated Seed Oil + Organosilicone Syl-Tac-EA Wilbur-Ellis Co.

Methylated Seed Oil + Organosilicone Turbulence Winfield Solutions, LLC

Vegetable Oil Amigo Loveland Products, Inc.

Vegetable Oil BeanOil Drexel Chemical Company

Vegetable Oil Competitor Wilbur-Ellis Co. 

Vegetable Oil Elite Natural Red River Specialties, Inc.

Vegetable Oil Motion Exacto, Inc.

Vegetable Oil Noble Winfield Solutions, LLC

Vegetable Oil Vegetoil Drexel Chemical Company

Fertilizer-based 

Nitrogen-based Actamaster Soluble Spray Adjuvant Loveland Products, Inc.

Nitrogen-based Actamaster Spray Adjuvant Loveland Products, Inc.

Nitrogen-based Alliance Winfield Solutions, LLC

Nitrogen-based AMS-All Drexel Chemical Company

Nitrogen-based AMS-Supreme Drexel Chemical Company

Nitrogen-based AMS-Xtra Drexel Chemical Company

Nitrogen-based Bronc Wilbur-Ellis Co.

Nitrogen-based Bronc Max Wilbur-Ellis Co. 

Nitrogen-based Bronc Max EDT Wilbur-Ellis Co.

Nitrogen-based Bronc Plus Dry Wilbur-Ellis Co.

Nitrogen-based Bronc Plus Dry EDT Wilbur-Ellis Co. 
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Adjuvant Type Trade Name Manufacturer ARBO2

Nitrogen-based Bronc Total Wilbur-Ellis Co.

Nitrogen-based Cayuse Plus Wilbur-Ellis Co.

Nitrogen-based Class Act NG Winfield Solutions, LLC 

Nitrogen-based Cornbelt Gardian Van Diest Supply Co.

Nitrogen-based Cornbelt Gardian Plus Van Diest Supply Co.

Nitrogen-based Corral AMS Liquid Winfield Solutions, LLC

Nitrogen-based Dispatch Loveland Products, Inc.

Nitrogen-based Dispatch 111 Loveland Products, Inc.

Nitrogen-based Dispatch 2N Loveland Products, Inc.

Nitrogen-based Dispatch AMS Loveland Products, Inc.

Nitrogen-based Flame Loveland Products, Inc.

Nitrogen-based Holzit Drexel Chemical Company

Nitrogen-based Nitro-Surf Drexel Chemical Company

Nitrogen-based Quest Helena Chemical Company

Nitrogen-based TransActive HC Helena Chemical Company

Special Function 

Buffering Agent Brimstone Wilbur-Ellis Co.

Buffering Agent BS-500 Drexel Chemical Company

Buffering Agent Buffers P.S. Helena Chemical Company

Buffering Agent Oblique Red River Specialties, Inc.

Buffering Agent Spray-Aide Miller Chem. & Fert. Corp.

Buffering Agent Tri-Fol Wilbur-Ellis Co.

Buffering Agent Yardage Exacto, Inc.

Colorants/Dyes Alligare Super Marking Dye Alligare, LLC

Colorants/Dyes BullsEye Milliken Chemical

Colorants/Dyes Elite Ruby Red River Specialties, Inc.

Colorants/Dyes Elite Sapphire Red River Specialties, Inc.

Colorants/Dyes Elite Sapphire WSB Red River Specialties, Inc.

Colorants/Dyes Elite Splendor Red River Specialties, Inc.

Colorants/Dyes Hash Mark Blue Liquid Exacto, Inc.

Colorants/Dyes Hash Mark Blue Liquid HC Exacto, Inc.

Colorants/Dyes Hash Mark Blue Powder Exacto, Inc.

Colorants/Dyes Hash Mark Green Liquid Exacto, Inc.

Colorants/Dyes Hash Mark Green Powder Exacto, Inc.

Colorants/Dyes Hi-Light Becker-Underwood

Colorants/Dyes Hi-Light WSP Becker-Underwood

Colorants/Dyes Marker Dye Loveland Products, Inc.

Colorants/Dyes Mark-It Blue Monterey AgResources

Colorants/Dyes Mark-It Red Monterey AgResources

Colorants/Dyes Mystic HC Winfield Solutions, LLC

Colorants/Dyes Signal Precision Laboratories, LLC

Colorants/Dyes SPI-Max Blue Spray Marker PROKoZ

Colorants/Dyes Spray Indicator XL Helena Chemical Company

Colorants/Dyes TurfTrax Loveland Products, Inc.

Colorants/Dyes TurfTrax Blue Spray Indicator Loveland Products, Inc.

Compatibility/Suspension Agent Blendex VHC Setre (Helena)

Compatibility/Suspension Agent Convert Precision Laboratories, LLC

Compatibility/Suspension Agent E Z MIX Loveland Products, Inc.

Compatibility/Suspension Agent Mix Drexel Chemical Company

Compatibility/Suspension Agent Support Loveland Products, Inc.

Defoaming Agent Alligare Anti-Foamer Alligare, LLC

Defoaming Agent Alligare Defoamer Alligare, LLC

Defoaming Agent Cornbelt Defoamer Van Diest Supply Co.

Defoaming Agent Defoamer Brewer International
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Adjuvant Type Trade Name Manufacturer ARBO2

Defoaming Agent Fast Break Winfield Solutions, LLC

Defoaming Agent Fighter-F 10 Loveland Products, Inc.

Defoaming Agent Fighter-F Dry Loveland Products, Inc.

Defoaming Agent Foam Buster Setre (Helena)

Defoaming Agent Foambuster Max Helena Chemical Company

Defoaming Agent Foam Fighter Miller Chem. & Fert. Corp.

Defoaming Agent Fome-Kil Drexel Chemical Company

Defoaming Agent FTF Defoamer Wilbur-Ellis Co.

Defoaming Agent Gundown Max Precision Laboratories, LLC

Defoaming Agent No Foam Wilbur-Ellis Co.

Defoaming Agent Red River Defoamer Red River Specialties, Inc.

Defoaming Agent Reverse Exacto, Inc.

Defoaming Agent Suppression Chemorse, Ltd

Defoaming Agent Tripleline Creative Marketing & Research, Inc.

Defoaming Agent Unfoamer Loveland Products, Inc.

Deposition Aid Agripharm Drift Control Walco International

Deposition Aid Alligare Downforce Alligare, LLC

Deposition Aid Alligare Pattern Alligare, LLC

Deposition Aid Bivert Wilbur-Ellis Co.

Deposition Aid Border AQ Precision Laboratories, LLC

Deposition Aid Chem-Trol Chemorse, Ltd

Deposition Aid Clasp Helena Chemical Company

Deposition Aid Compadre Loveland Products, Inc.

Deposition Aid Coverage G-20 Wilbur-Ellis Co.

Deposition Aid Crosshair Wilbur-Ellis Co.

Deposition Aid CWC Sharpshooter CWC Chemical, Inc.

Deposition Aid Cygnet Plus Brewer International 

Deposition Aid Direct Precision Laboratories, LLC

Deposition Aid Droplex Winfield Solutions, LLC

Deposition Aid EDT Concentrate Wilbur-Ellis Co.

Deposition Aid Elite Secure Ultra Red River Specialties, Inc.

Deposition Aid Exit Miller Chem. & Fert. Corp.

Deposition Aid Grounded Helena Chemical Company

Deposition Aid Grounded - CA Helena Chemical Company

Deposition Aid Infuse Loveland Products, Inc.

Deposition Aid Intac Plus Loveland Products, Inc.

Deposition Aid Interlock Winfield Solutions, LLC 

Deposition Aid Liberate Loveland Products, Inc. 

Deposition Aid LOX Drexel Chemical Company

Deposition Aid LOX PLUS Drexel Chemical Company

Deposition Aid Mist-Control Miller Chem. & Fert. Corp.

Deposition Aid Offside Exacto, Inc.

Deposition Aid Pointblank Helena Chemical Company

Deposition Aid Poly Control 2 Brewer International

Deposition Aid ProMate Impel Helena Chemical Company

Deposition Aid Reign Loveland Products, Inc.

Deposition Aid Reign LC Loveland Products, Inc.

Deposition Aid Secure Ultra Red River Specialties, Inc.

Deposition Aid Sta’-Put Setre (Helena)

Deposition Aid Strike Zone DF Helena Chemical Company

Deposition Aid Sustain Miller Chem. & Fert. Corp.

Deposition Aid Syndetic Chemorse, Ltd

Deposition Aid Volare DC Precision Laboratories, LLC

Deposition Aid Weather Gard Loveland Products, Inc.
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Adjuvant Type Trade Name Manufacturer ARBO2

Diluent/Deposition Agent Bark Oil Crop Production Services

Diluent/Deposition Agent Bark Oil EC Crop Production Services

Diluent/Deposition Agent Elite Premier Red River Specialties, Inc.

Diluent/Deposition Agent Elite Premier Blue Red River Specialties, Inc.

Diluent/Deposition Agent Hy-Grade EC CWC Chemical, Inc.

Diluent/Deposition Agent Hy-Grade I CWC Chemical, Inc.

Diluent/Deposition Agent Improved JLB Oil Plus Brewer International

Diluent/Deposition Agent In-Place Wilbur-Ellis Co.

Diluent/Deposition Agent JLB Oil Plus Brewer International

Diluent/Deposition Agent Red River Basal Oil Red River Specialties, Inc.

Diluent/Deposition Agent Thinvert TRU Waldrum Specialties, Inc.

Diluent/Deposition Agent Thinvert Concentrate Waldrum Specialties, Inc.

Diluent/Deposition Agent W.E.B. Oil Wilbur-Ellis Co.

Foam Marker Align Helena Chemical Company

Foam Marker F.M.-160 Drexel Chemical Company

Foam Marker R-160 Wilbur-Ellis Co.

Foam Marker Red River Foam Marker Red River Specialties, Inc.

Foam Marker Trekker Trax Loveland Products, Inc.

Foam Marker Tuff Trax Foam Concentrate Loveland Products, Inc.

Invert Emulsion Agent Redi-vert II Wilbur-Ellis Co.

Tank Cleaner All Clear Loveland Products, Inc.

Tank Cleaner Back Field Exacto, Inc.

Tank Cleaner Cornbelt Tank-Aid Van Diest Supply Co.

Tank Cleaner Elite Vigor Red River Specialties, Inc.

Tank Cleaner Kutter Wilbur-Ellis Co.

Tank Cleaner Neutral-Clean Wilbur-Ellis Co.

Tank Cleaner Pro Tank Winfield Solutions, LLC

Tank Cleaner Red River Tank Cleaner Red River Specialties, Inc.

Tank Cleaner SSC-11 Wilbur-Ellis Co.

Tank Cleaner Tank and Equipment Cleaner Loveland Products, Inc.

Tank Cleaner Wipe Out Helena Chemical Company

Water Conditioning AccuQuest WM Helena Chemical Company

Water Conditioning Alligare Water Conditioner Alligare, LLC

Water Conditioning Blendmaster Loveland Products, Inc.

Water Conditioning Breeze Winfield Solutions, LLC

Water Conditioning Choice Loveland Products, Inc.

Water Conditioning Choice Weather Master Loveland Products, Inc.

Water Conditioning Choice Xtra Loveland Products, Inc.

Water Conditioning Climb Wilbur-Ellis Co.

Water Conditioning Completion Exacto, Inc.

Water Conditioning Cornbelt N-Tense Van Diest Supply Co.

Water Conditioning Cut-Rate Wilbur-Ellis Co. 

Water Conditioning Elite Imperial Red River Specialties, Inc.

Water Conditioning Hel-Fire Helena Chemical Company

Water Conditioning Import Precision Laboratories, LLC

Water Conditioning Sequestra Drexel Chemical Company

Water Conditioning Smoke Helena Chemical Company

Water Conditioning Transport LpH Precision Laboratories, LLC

Water Conditioning Transport Plus Precision Laboratories, LLC

1. Approved list as of January 6, 2017.

2. Approved for use near water under ARBO II
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Appendix F: Herbicide Risk 

Assessment Summaries

The risk tables presented in this appendix are used in the individual 

analysis in Chapter 3 and Appendix G. This appendix was adapted 

from the Oregon FEIS (USDI 2010a:85-91).

EPA Labels

The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) 

establishes procedures for the registration, classification, and 

regulation of all herbicides. Before any herbicides may be sold 

legally, the EPA must register it. The EPA may classify an herbicide 

for general use if it determines that the herbicide is not likely to 

cause unreasonable adverse effects to applicators or the 

environment, or it may be classified for restricted use if the 

herbicide must be applied by a certified applicator and in 

accordance with other restrictions. Aquatic herbicides require extra testing over and above what is required for 

the normal registration process before they can be registered for aquatic application. This includes dissipation 

studies in water and aquatic sediments, accumulation in non-target organisms, and fish and shellfish tolerances. 

The herbicide label is a legal document specifying allowable uses; all applicators that apply herbicides on public 

lands must comply with the application rates, uses, 

handling, and all other instructions on the herbicide 

label, and where more restrictive, the rates, uses, 

and handling instructions developed by the BLM.

In addition to sub-chronic and chronic toxicity, EPA 

herbicide registration looks at the acute toxicity of 

an herbicide. Acute toxicity is the most common 

basis for comparing the relative toxicities of herbicides. Acute toxicity can be measured by LD5028. LD50 (LD = lethal 

dose) represents the amount of herbicide that results in the death of 50 percent of a test population. Therefore, 

the lower the LD50, the more toxic the herbicide. Table F-1 shows the three categories that the EPA uses for 

classifying herbicides (USDI 1992a).

Table F-1. Herbicide Label Categories

Categories Signal Word 

Required on Label

Oral LD50

(mg./kg.)

Dermal LD50 

(mg./kg.)

Inhalation LD50

(mg./kg.)

Probable Oral Lethal 

Dose for 150 lb. Human

I – Highly Toxic DANGER, POISON, 

skull & crossbones

Up to and 

including 50

Up to and 

including 200

Up to and 

including 0.2

A few drops to a 

teaspoonful

II – Moderately 

Toxic WARNING From 50 to 500 From 200 to 2,000 From 0.2 to 2 Over one teaspoonful to one ounce

III – Slightly 

Toxic CAUTION From 500 to 5,000

From 2,000 to 

20,000 From 2 to 20 Over one ounce to one pint or one pound.

In addition, the EPA has established Levels of Concern (LOC) for herbicides, which is the dose of the herbicide 

above which effects would be expected. The LOCs are used by EPA for registration, and to indicate potential risk to 

 28 or LC50 (lethal concentration) in the case of aquatic organisms.

EPA terms

LD50 Lethal Dose to 50% of the population

LOC Level of Concern

NOAEL No Observed Adverse Effect Level

LOAEL Lowest Observed Adverse Effect Level

BLM terms

RQ Risk Quotient

ECC Estimated Exposure Concentration

TRV Toxicity Reference Value

ARI Aggregated Risk Index

Forest Service terms

HQ Hazard Quotient

RfD Reference Dose

TI Toxicity Index

Acute toxicity: The quality or potential of a substance to cause injury or 

illness shortly after exposure through a single or short-term exposure.

Chronic toxicity: The ability of a substance or mixture of substances to 

cause harmful effects over an extended period, usually upon repeated or 

continuous exposure sometimes lasting for the entire life of the exposed 

organism.
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205

non-target organisms and the need to consider regulatory action (USEPA 2007). In the absence of information 

indicating otherwise, the LOC is generally 1/10th of the Lowest Observed Adverse Effect Level (LOAEL); that is, the 

lowest dose level where there was a statistically significant increase in frequency or severity of adverse effects29 to 

the test organism. In some cases, no adverse reaction happens at any dose (or at any reasonable dose), and the 

LOC is the No Observed Adverse Effect Level (NOAEL). LOCs include uncertainty factors based on the amount and 

nature of the toxicity testing on which they are based.

Risk Assessments

One of the Purposes identified in Chapter 1 of this EA is: Prevent control treatments from having unacceptable 

adverse effects to applicators and the public, to desirable flora and fauna, and to soil, air, and water. To help 

address this Purpose, this EA relies on BLM and Forest Service-prepared Human Health and Ecological Risk 

Assessments for the herbicides analyzed in this EA. These complete Risk Assessments are included in the Oregon 

FEIS as Appendix 8: Risk Assessments (uncirculated) and the 2007 and 2016 PEISs. The Risk Assessments are used 

to quantitatively evaluate the probability (i.e., risk) that herbicide use in wildland settings might pose harm to 

humans or other species in the environment. As such, they address many of the risks that would be faced by 

humans, plants, and animals, including federally listed and other Special Status species, from the use of the 

herbicides. The level of detail in the Risk Assessments far exceeds that normally found in EPA’s registration 

examination.

Risk is defined as the likelihood that an effect (injury, disease, death, or environmental damage) may result from a 

specific set of circumstances. It can be expressed in quantitative or qualitative terms. While all human activities 

carry some degree of risk, some risks are known with a relatively high degree of accuracy because data have been 

collected on the historical occurrence of related problems (e.g., lung cancer caused by smoking, auto accidents 

caused by alcohol impairment, and fatalities resulting from airplane travel). For several reasons, risks associated 

with exposure to herbicides (at least in wildland settings) cannot be so readily determined. The Risk Assessments 

help evaluate the risks resulting from these situations.

Risk Assessments are necessarily done on a surrogate species in laboratory conditions, identified to represent a 

species group, as toxicological data does not exist for most native non-target species. Survival, growth, 

reproduction, and other important sub-lethal processes of both terrestrial and aquatic non-target species were 

considered. Assessments considered acute and chronic toxicity data. Exposures of receptors30 to direct spray, 

surface runoff, wind erosion, and accidental spills were analyzed.

Most of the Human Health and Ecological Risk Assessments were developed by the BLM for the 2007 PEIS, the 

2016 PEIS, or by the Forest Service for the 2005 Pacific Northwest Region Invasive Plant Program EIS (see Table F2). The Risk Assessments, related separate analyses, and the PEISs include analysis of degradates and other 

ingredients for which information is available and not constrained by confidential business information 

restrictions. Preparing a Risk Assessment for every conceivable combination of herbicide, tank mix, adjuvants 

(including surfactants), and other possible mixtures is not feasible, as the BLM cannot prepare hundreds of Risk 

Assessments, and the cost would be exorbitant. To the degree a toxic substance is known to pose a human or 

ecological risk, the BLM has undertaken analysis to assess its impacts through Risk Assessments. More detailed 

information about uncertainty in the Risk Assessment process is included in Appendix 13 of the Oregon FEIS.

 29 Lethal or sub-lethal. 30 An ecological entity such as a human, fish, plant, or slug.
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206

Table F-2. Human Health and Ecological Risk Assessment Sources 

When evaluating risks from the use of herbicides 

proposed in a NEPA planning document, reliance 

on EPA’s herbicide registration process as the sole 

demonstration of safety is insufficient. The U.S. 

Forest Service and BLM were involved in court 

cases in the early 1980s that specifically addressed 

this question (principally Save Our Ecosystems v. 

Clark, 747 F.2d 1240, 1248 (9th Cir. 1984) and 

Southern Oregon Citizens v. Clark, 720 F. 2d 1475, 

1480 (9th Cir. 1983)). These court decisions and 

others affirmed that although the BLM can use 

EPA toxicology data, it is still required to do an 

independent assessment of the potential risks of 

using herbicides rather than relying on FIFRA 

registration alone. The Courts have also found that 

FIFRA does not require the same examination of 

impacts that the BLM is required to undertake 

under NEPA. Further, Risk Assessments consider 

data collected from both published scientific 

literature and data submitted to EPA to support 

FIFRA product registration, whereas EPA utilizes 

the latter data only. The EPA also considers many 

wildland herbicide uses to be minor. Thus, the project-specific application rates, spectrum of target and non-target 

organisms, and specialized exposure scenarios evaluated by the BLM are frequently not evaluated by EPA in its 

generalized registration assessments.

The Risk Assessments and their distillation in the PEIS and Oregon FEIS are the source for much of the individual 

herbicide information presented in each of the effects analyses in this EA, including the high-moderate-low risk 

categories shown in the tables in this appendix.

Drift

Assuming non-target animals and plants are not directly sprayed, drift is the process most likely to result in 

herbicides getting onto non-target plants and animals, as well as herbicides moving outside the treatment area. 

Drift, defined as that part of a sprayed herbicide that is moved from the target area by wind while it is still 

airborne, is primarily dependent upon the elevation of the spray nozzle, droplet size and air movement. The 

smaller the droplet, the longer it stays suspended and the farther it can travel. Drift is one exposure scenario 

examined in the Risk Assessments and summarized on the risk tables at the end of this appendix.

Spray drift can be reduced by increasing droplet size since wind will move large droplets less than small droplets. 

Droplet size can be increased by: 1) reducing spray pressure; 2) increasing nozzle orifice size; 3) using special drift 

reduction nozzles; and 4) using additives that increase spray viscosity. Commercial drift reduction agents are 

available that are designed to reduce drift beyond the capabilities of the determinants described above. These 

products create larger and more cohesive droplets that are less apt to break into small particles as they fall 

through the air. They reduce the percentage of smaller, lighter particles, which are most apt to drift. Standard 

Operating Procedures for air quality provide techniques for controlling drift, including specifying selection of 

equipment that produces 200 to 800-micron diameter droplets.

Drift includes droplets and vapor. In general, however, herbicides have very low vapor pressures and BLM spray 

mixtures do not produce much vapor. One study showed that with more volatile insecticides, little or no vapor 

Herbicide Human Health Ecological

2,4-D BLM (2016)

Aminopyralid BLM (2016)

Chlorsulfuron Forest Service BLM (2007)

Clopyralid BLM (2016)

Dicamba Forest Service

Dicamba + diflufenzopyr NA BLM (2007)

Diflufenzopyr BLM (2007) NA

Fluroxypyr BLM (2016)

Glyphosate Forest Service

Hexazinone Forest Service

Imazapic BLM (2007)

Imazapyr Forest Service

Metsulfuron methyl Forest Service

Picloram Forest Service

Rimsulfuron BLM (2016)

Sulfometuron methyl BLM (2007)

Triclopyr Forest Service

Herbicides analyzed for Research and Demonstration

Fluazifop-P-butyl Forest Service1

Sethoxydim Forest Service2

1. Scoping/screening level Risk Assessment, not adopted by the BLM.

2. Not adopted by the BLM
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drift was detected 9-27 meters downwind for insecticides with vapor pressures less than 1x10-4 mm Hg 

(Woodward et al. 1997). All of the herbicides covered by the EIS have very low vapor pressures (maximum is 4x10-

6 mm Hg and they range to as low as 5.5x10-16 mm Hg; Vencill et al. 2002).

High, Moderate, and Low Risk in BLM and Forest 

Service Risk Assessments

The Risk Assessments measure both acute toxicity and chronic toxicity. Chronic toxicity is difficult to measure, 

especially in humans, but shows the results of sub-lethal doses that could result in cumulative deposits that could 

cause long-term problems in a vital body function. There is no standard measure for chronic toxicity.

BLM Ecological Risk Assessments

The BLM Ecological Risk Assessments established a Risk Quotient (RQ) for every herbicide and defined risk 

categories as follows:

0 No Risk RQ < most conservative LOC for the species 

L Low Risk RQ = 1 to 10 times the most conservative LOC for the species 

M Moderate Risk RQ = 10 to 100 times the most conservative LOC for the species 

(generally equal to LOAEL to 10-times LOAEL) 

H High Risk RQ > 100 times the most conservative LOC for the species 

The RQ is calculated using the Estimated Exposure Concentration (EEC) and the Toxicity Reference Value (TRV). The 

EEC is the dose that an organism would be exposed to under the test scenario; e.g., consumption would indicate 

the amount of herbicide eaten on a sprayed material (a cow eating only sprayed grass for a day, for example), and 

direct spray indicates that the organism was sprayed directly with a wand or was in a flight path (a non-target plant 

species, for example). The TRV is the toxicity of the herbicide – usually the LOAEL or NOAEL. The RQ is the EEC 

divided by the TRV. An uncertainty factor can be brought in if it is thought that a species (or a particular individual 

within the species) is particularly susceptible to herbicide use, or that the single dose does not represent long-term 

exposure.

For example, the TRV (the dose that can be consumed with a potentially adverse effect) for a mule deer consuming 

vegetation contaminated with bromacil31 is 170 milligrams per kilogram of body weight per day (a mule deer 

weighs an estimated 70 kg.). Assuming a daily consumption rate of 6.2 kg. of forage, all contaminated with 

bromacil sprayed at the typical application rate (4 lbs./acre), the EEC (the amount of herbicide that the mule deer 

will be exposed to by eating the contaminated vegetation) is 33.7 milligrams per kilograms of body weight per day. 

Thus, the RQ is 33.7 mg./kg. divided by 170 mg./kg., or 0.198, which is a risk category of 0 (or no risk).

Tank Mixes - The BLM evaluated risks from mixing two herbicides together in a tank mix. The BLM assumed that 

products in a tank mix act in an additive manner. Therefore, to simulate a tank mix of two herbicides RQs for those 

two herbicides were combined (details provided in the individual Risk Assessments). The application rates within 

the tank mix are not necessarily the same as those of each individual active ingredient applied alone. The percent 

of RQs exceeding LOCs for each of the ten BLM herbicide active ingredients was compared to the percent of RQs 

exceeding LOCs for tank mixes, to determine whether additional risks were predicted for tank mixes.

 31 An herbicide not included in this analysis.
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BLM Human Health Risk Assessments (2007 and 2016)

The BLM Human Health Risk Assessments used the Aggregated Risk Index (ARI) and defined risk categories as 

follows: 

0 No Risk Majority of ARIs > 1 

L Low Risk Majority of ARIs < 1 but > 0.1 

M Moderate Risk Majority of ARIs < 0.1 but > 0.01 

H High Risk Majority of ARIs < 0.01 

The ARI is a formula for combining LOCs for all exposure avenues (oral, dermal, inhalation), each with different 

uncertainty factors, and comparing them with the exposure levels that would occur in the scenarios in the Risk 

Assessments. ARIs less than 1 indicate a concern from at least one of the exposure avenues (USEPA 2001:51-55).

Forest Service Risk Assessments

The Forest Service Risk Assessments are very similar to the BLM’s Ecological Risk Assessments. The Forest Service 

Risk Assessments established a Hazard Quotient (HQ) for every herbicide and established risk categories as follows:

0 No Risk HQ < LOC for the species 

L Low Risk HQ = 1 to 10 times the LOC32 for the species 

M Moderate Risk HQ = 10 to 100 times the LOC for the species 

H High Risk HQ > 100 times the LOC for the species 

Figure F-1. Basis for Risk Assessments

The HQ is calculated using the Reference Dose (RfD) and 

the Toxicity Index (TI). The RfD is the dose that an 

organism would be exposed to under the test scenario; 

the TI is the toxicity of the herbicide and the HQ is the 

RfD divided by the TI. An uncertainty factor can be 

brought in if it is thought that a species (or a particular 

i

Hazard 

Identification

Dose-Response 

Assessment

Risk 

Characterization

Exposure 

Assessment

ndividual within the species) is particularly susceptible 

to herbicide use, or that the single dose does not 

represent long-term exposure.

Figure F-1 shows the basis for Risk Assessments, which 

consists of the following parts:

• Hazard Identification: what are the dangers inherent 

with the herbicide? (e.g., endocrine disruption, cancer 

causing, etc.)

• Exposure Assessment: who could come into contact 

and how much? (specific exposure scenarios)

• Dose Response Assessment: how much is too much? At what dose are observable effects observed?

• Risk Characterization: indicates whether or not there is a plausible basis for concern (HQ or RQ).

 

32 As noted in the previous discussion, LOCs are generally set at 1/10th of the LOAEL. Thus, an HQ of 1 to 10 times LOC is 

equivalent to an HQ of 0.1 to 1 in the 2005 Forest Service Invasive Plant EIS (USDA 2005:4-73). The Forest Service EIS goes on to 

explain “The threshold is intended to help reviewers distinguish moderate risks (HQ=2 to 10 [HQ = 20-100 in this EIS]), which 

could in most cases be mitigated through exposure-reducing project design criteria from significant health risks (HQ>10 

[HQ>100 in this EIS]) that could be difficult to mitigate if Worst-Case situations occur at the project level. For specific situations 

where a HQ>10 [HQ>100 in this EIS] is identified, the specific physiologic effect and the relationship between the NOAEL and 

the LOAEL may be evaluated to more precisely determine whether a toxic effect is actually likely to occur (Durkin, personal 

communication).” (USDA 2005:4-73) 
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Stated another way, the lower range for the L, or low, risk category is theoretically the level at which an effect 

began to be discernable in testing or modeling (theoretically, because uncertainty factors have the effect of 

reducing the dose identified as having the adverse effect). The minimum identified effect may have been skin or 

eye irritation, leaf damage, for example. Uncertainty factors are added to address hypersensitive individuals, or 

accommodate uncertainties in the measurements, such as inferring effects to one species based on actual tests on 

other species. Uncertainty factors are typically multiples of 10, so the assumed Lowest Observable Effects (LOAEL) 

dose could have been inflated 10, 100, or even 1,000 times for uncertainties. Thus, exposure of the average 

individual to the dose identified as having an effect, probably would not have an effect. Nevertheless, the L or low 

rating indicates risks start at that point. Moderate (M) risk categories indicate risk starts at doses one-tenth those 

of the low ratings; high is one-hundredth of the testing scenario dose. Testing scenarios are severe – e.g., soaking 

the test animal – so Standard Operating Procedures and Mitigation Measures such as buffers, wind speed limits, 

and so forth, as well as required safety equipment, limit exposure to substantially less than tested doses. For 

herbicides with moderate and high risk categories for a particular receptor, special cautions are implemented. For 

example, buffers for Special Status plant species are as large as 1,500 feet for some herbicides (see Conservation 

Measures in Appendix D). The zero, low, moderate, or high human health risk categories shown on Tables F-3 

through F-8 are more conservative than the EPA ratings used to apply the Caution, Warning, or Danger/Poison 

signal words to herbicide labels.

The Risk Assessments are summarized on tables showing herbicide risk categories at BLM maximum and typical 

application rates to vegetation, wildlife, and humans, in a variety of application scenarios. Tables F-3 and F-6 show 

herbicide risks to vegetation, from BLM and Forest Service Risk Assessments respectively. Tables F-4 and F-7 show 

herbicide risks to wildlife, fish, and aquatic invertebrates and Tables F-5 and F-8 show the risks to human health. 

Further information about the Human Health Risk Assessments can be found in the Human Health and Safety

section of Chapter 4 of the Oregon FEIS.

Uncertainty in the Risk Assessment Process

The Risk Assessments conducted by the BLM and Forest Service incorporate various conservative assumptions to 

compensate for uncertainties in the Risk Assessment process. Within any of the steps of the human health risk 

evaluation process, assumptions were made due to a lack of absolute scientific knowledge. Some of the 

assumptions are supported by considerable scientific evidence, while others have less support. Every assumption 

introduces some degree of uncertainty into the risk evaluation process. Regulatory risk evaluation methodology 

requires that conservative assumptions be made throughout the Risk Assessment process to ensure that public 

health is protected. This conservatism, both in estimating exposures and in setting toxicity levels likely led to an 

exaggeration of the real risks of the vegetation management program to err on the side of protecting human 

health and other species.

Cumulative effects of long-term use of herbicides may have different outcomes than Risk Assessments can 

anticipate. Although identification of adverse effects from chronic exposures is one of the parameters examined in 

the Risk Assessment process, it is possible there are long-term sub-lethal effects on reproductive or migratory 

behavior from low concentrations of herbicides or additives that are not documented in the Risk Assessments.

See additional information about uncertainty near the end of Appendix 13 of the Oregon FEIS.
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Table F-3. BLM-Evaluated Herbicide Risk Categories1 for Vegetation

Application Scenario Chlorsulfuron Imazapic Diflufenzopyr + 

Dicamba Fluridone Sulfometuron Aminopyralid Fluroxypyr Rimsulfuron

Typ2 Max2 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max

Direct Spray 

Terrestrial plants H1 H L M M HNE NE 0 L H H H H H H

[1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1]

Special Status terrestrial plants H H L M H HNE NE

H H H H H H H H

[1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1] [1:1]

Aquatic plants, pond M M L L M M 0 0 H H 0 0 0 L H M

[1:2] [2:2] [1:2] [2:2] [1:2] [1:2] [2:2] [2:2] [2:2] [2:2] [2:2] [4:4] [2:2] [2:4] [1:2] [2:4]

Aquatic plants, stream M M L M M H 0 0 H H 0 0 0 0 H H

[2:2] [2:2] [2:2] [2:2] [1:2] [1:2] [2:2] [2:2] [2:2] [2:2] [2:2] [2:2] [2:2] [2:2] [1:2] [1:2]

Accidental Spill to a Pond

Aquatic plants, pond NE

H

NE

H

NE

M

NE

L

NE

H 0 0 0 L H M

[1:2] [2:2] [1:1] [2:2] [2:2] [2:2] [4:4] [2:2] [2:4] [1:2] [2:4]

Off-Site Drift

Terrestrial plants M M 0 0 0 0 NE NE 0 0 L L L L L L

[5:12] [8:12] [18:18] [13:18] [5:6] [4:6] [12:12] [12:12] [10:18] [10:18] [11:18] [11:18] [9:18] [9:18]

Special Status terrestrial plants M M 0 0 L LNE NE

H H L L L L L L

[7:12] [7:12] [17:18] [13:18] [3:6] [4:6] [5:12] [8:12] [10:18] [10:18] [13:18] [11:18] [9:18] [8:18]

Aquatic plants, pond 0 0 0 0 0 0 NE NE

L L 0 0 0 0 0 0

[24:24] [24:24] [36:36] [34:36] [12:12] [12:12] [13:24] [12:24] [36:36] [36:36] [36:36] [36:36] [24:36] [23:36]

Aquatic plants, stream 0 0 0 0 0 0 NE NE

L L 0 0 0 0 0 0

[24:24] [22:24] [36:36] [33:36] [8:12] [6:12] [14:24] [10:24] [36:36] [36:36] [36:36] [36:36] [24:36] [23:36]

Surface Runoff

Terrestrial plants 0 0 0 0 0 0 NE NE 0 0 0 0 0 0 0 0

[42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42]

Special Status terrestrial plants 0 0 0 0 0 0 NE NE 0 0 0 0 0 0 0 0

[42:42] [42:42] [42:42] [42:42] [34:42] [33:42] [32:42] [28:42] [42:42] [42:42] [42:42] [42:42] [42:42] [42:42]

Aquatic plants, pond 0 0 0 0 0 0 NE NE

L L 0 0 0 0 0 0

[64:84] [53:84] [80:84] [62:84] [70:84] [67:84] [42:84] [38:84] [84:84] [84:84] [84:84] [84:84] [55:84] [54:84]

Aquatic plants, stream 0 0 0 0 0 0 NE NE 0 0 0 0 0 0 0 0

[80:84] [77:84] [84:84] [83:84] [84:84] [84:84] [69:84] [60:84] [84:84] [84:84] [84:84] [84:84] [84:84] [84:84]

Wind Erosion

Terrestrial plants 0 0 0 0 0 0 NE NE 0 0 0 0 0 0 0 0

[9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [8:9] [9:9] [8:9] [8:9] [8:9]

Special Status terrestrial plants 0 0 0 0 0 0 NE NE 0 0 0 0 0 0 0 0

[9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [9:9] [8:9] [8:9] [8:9] [7:9] [8:9] [8:9]

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (majority of RQs < most conservative LOC for non-Special Status species); L = Low risk (majority of RQs 1-10x most conservative LOC for non-Special Status species); M = Moderate risk (majority 

of RQs 10-100x most conservative LOC for non-Special Status species); H = High risk (majority of RQs >100 most conservative LOC for non-Special Status species); and NE = Not evaluated. The Risk Category is based on the 

risk level of the majority of risk quotients observed in any of the scenarios for a given exposure group and receptor type. See more information at the risk tables in Chapter 4 of the Ecological Risk Assessments (ENSR 2005a-
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211

f), AECOM 2014a, b, 2015) to determine the specific scenarios that result in the displayed level of risk for a given receptor group. The number in brackets represents the number of RQs in the indicated risk category: number 

of scenarios evaluated.

2. Typ = Typical application rate; and Max = Maximum application rate.

Table F-4. BLM-Evaluated Herbicide Risk Categories1 for Wildlife, Fish, and Aquatic Species

Application Scenario Chlorsulfuron Imazapic Diflufenzopyr + 

Dicamba Fluridone Sulfometuron methyl Aminopyralid Fluroxypyr Rimsulfuron

Typ2 Max2 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max

Direct Spray

Non Special Status Species

Small mammal – 100% absorption 01 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Pollinating insect – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small mammal – 1st order dermal absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Fish pond 0 0 0 0 0 0 0 0 0 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

Fish stream 0 0 0 0 0 0 0 L 0 0 0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

Aquatic invertebrates pond 0 0 0 0 0 0 0 L 0 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

Aquatic invertebrates stream 0 0 0 0 0 0 0 L 0 0 0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

Special Status Species

Small mammal – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Pollinating insect – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 L L 0 0

Small mammal – 1st order dermal absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Fish pond 0 0 0 0 0 0 0 M 0 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[2:4]

0

[2:2]

0

[4:4]

Fish stream 0 0 0 0 0 0 0 L 0 0 0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

Aquatic invertebrates pond 0 0 0 0 0 0 0 H 0 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[3:4]

0

[2:2]

0

[4:4]

Aquatic invertebrates stream 0 0 0 0 0 0 0 L 0 0 0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

0

[2:2]

Indirect Contact with Foliage After Direct Spray

Non Special Status Species

Small mammal – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Pollinating insect – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small mammal – 1st order dermal absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Special Status Species

Small mammal – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Pollinating insect – 100% absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small mammal – 1st order dermal absorption 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Ingestion of Food Items Contaminated by Direct Spray
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Application Scenario Chlorsulfuron Imazapic Diflufenzopyr + 

Dicamba Fluridone Sulfometuron methyl Aminopyralid Fluroxypyr Rimsulfuron

Typ2 Max2 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max

Non Special Status Species

Small mammalian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small mammalian herbivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian herbivore – chronic 0 0 0 0 L M 0 0 0 0 0 0 0 0 0 0

Small avian insectivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small avian insectivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large avian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large avian herbivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian carnivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian carnivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Special Status Species

Small mammalian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small mammalian herbivore – chronic 0 0 0 0 0 0 0 L 0 0 0 0 0 0 0 0

Large mammalian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian herbivore – chronic 0 0 0 0 L M 0 0 0 0 0 0 0 0 0 0

Small avian insectivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Small avian insectivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large avian herbivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large avian herbivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian carnivore – acute 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Large mammalian carnivore – chronic 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Accidental Spill to Pond

Non Special Status Species

Fish pond NE 0 NE 0 NE 0 NE M NE 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

Aquatic invertebrates, pond NE 0 NE 0 NE 0 NE H NE 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

0

[2:2]

0

[4:4]

Special Status Species

Fish pond NE 0 NE 0 NE 0 NE M NE 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[2:4]

0

[2:2]

0

[4:4]

Aquatic invertebrates, pond NE 0 NE 0 NE 0 NE H NE 0 0

[2:2]

0

[4:4]

0

[2:2]

0

[3:4]

0

[2:2]

0

[4:4]

Off-Site Drift

Non Special Status Species

Fish, pond 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Fish, stream 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]
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Application Scenario Chlorsulfuron Imazapic Diflufenzopyr + 

Dicamba Fluridone Sulfometuron methyl Aminopyralid Fluroxypyr Rimsulfuron

Typ2 Max2 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max

Aquatic invertebrates, pond 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Aquatic invertebrates, stream 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Special Status Species

Fish, pond 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Fish, stream 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Aquatic invertebrates, pond 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Aquatic invertebrates, stream 0 0 0 0 0 0 NE NE 0 0 0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

0

[36:36]

Surface Runoff

Non Special Status Species

Fish, pond 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Fish, stream 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Aquatic invertebrates, pond 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Aquatic invertebrates, stream 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Special Status Species

Fish, pond 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Fish, stream 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Aquatic invertebrates, pond 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Aquatic invertebrates, stream 0 0 0 0 0 0 NE NE 0 0 0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

0

[84:84]

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (majority of RQs < most conservative LOC for non-Special Status species); L = Low risk (majority of RQs 1-10x most conservative LOC for non-Special Status species); M = Moderate risk 

(majority of RQs 10-100x most conservative LOC for non-Special Status species); H = High risk (majority of RQs >100 most conservative LOC for non-Special Status species); and NE = Not evaluated. The risk category is based 

on the risk level of the majority of risk quotients observed in any of the scenarios for a given exposure group and receptor type. See the risk tables in Chapter 4 of the Ecological Risk Assessments (ENSR 2005a-f, AECOM 

2014a, b, 2015) to determine the specific scenarios that result in the displayed level of risk for a given receptor group. The number in brackets represents the number of RQs in the indicated risk category: number of 

scenarios evaluated.

2. Typ = Typical application rate; and Max = Maximum application rate.
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Table F-5. BLM-Evaluated Herbicide Risk Categories1 for Human Health

Receptor Diflufenzopyr Fluridone Imazapic Sulfometuron Aminopyralid Fluroxypyr Rimsulfuron3

Typ2 Max2 Accid Typ Max Accid Typ Max Accid Typ Max Accid Typ Max Accid Typ Max Accid Typ Max Accid

Hiker/hunter (adult) 01 0 0 0 0 0 NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Berry picker (child) 0 0 0 0 0 L NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Berry picker (adult) 0 0 0 0 0 0 NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Angler (adult) 0 0 0 0 0 0 NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Residential – contaminated water (child) 0 0 0 0 0 L NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Residential – contaminated water (adult) 0 0 0 0 0 L NC NC NE NC NC NE NC NC NE NC NC NE 0 0 0

Native American (child) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Native American (adult) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Swimmer (child) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NE NE NE

Swimmer (adult) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NE NE NE

Human/backpack - applicator/mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Human/horseback - applicator 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Human/horseback - mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Human/horseback - applicator/mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

ATV – applicator4 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

ATV - mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

ATV - applicator/mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Truck - applicator4 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Truck - mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Truck - applicator/mixer/loader 0 0 NE 0 0 L-H 0 0 NE 0 0 NE 0 0 NE 0 0 NE 0 0 L - M

Boat - applicator NE NE NE 0 0 L-H NE NE NE NE NE NE NE NE NE NE NE NE NE NE NE

Boat - mixer/loader NE NE NE 0 0 L-H NE NE NE NE NE NE NE NE NE NE NE NE NE NE NE

Boat - applicator/mixer/loader NE NE NE 0 0 L-H NE NE NE NE NE NE NE NE NE NE NE NE NE NE NE

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (majority of ARIs > 1); L = Low risk (majority of ARIs >1 but < 0.1); M = Moderate risk (majority of ARIs > 0.1 but < 0.01); H = High risk (majority of ARIs < 0.01); NE = Not evaluated; and NC = Not 

Calculated (based on toxicity assessment, no dose response values are available due to low toxicity. The reported risk category represents the typical/most common risk level for estimated risks from various time periods. 

See the Vegetation Treatments Programmatic EISs Human Health Risk Assessments Final Reports (ENSR 2005g, AECOM 2014c) and for the range of risk levels for each scenario.

2. Typ = Typical application rate; Max = Maximum application rate; and Accid = Accidental rate. Typical and maximum application rate categories include short-, intermediate-, and long-term exposures. Accidental scenario 

category includes accidents with herbicide mixed at both the typical and maximum application rates and with a concentrated herbicide.

3. For all worker receptors accidentally exposed to rimsulfuron, there is low risk from exposure to solutions mixed with the typical application rate, moderate risk from exposure to solutions mixed with the maximum 

application rate.

4. ATV and Truck categories include spot and boom/broadcast application scenarios.
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Table F-6. Forest Service-Evaluated Herbicide Risk Categories1 for Vegetation

Scenario 2,4-D2, 4 Clopyralid Dicamba Glyphosate

3, 4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.3756 Typ Max

Terrestrial Plants

Direct spray, susceptible 

plants H1 H H H H H H H H H H H H H H H H H M M M M

Direct spray, tolerant plants L L 0 L 0 0 L M M M L L L M L M 0 L 0 0 M M

Off-site drift, low boom, 

susceptible plants

L L L M L H M M L M M H L M H H L M 0 0 0 0

[3:6] [3:6] [4:6] [3:6] [3:6] [3:6] [3:6] [4:6] [4:6] [3:6] [3:6] [3:6] [4:6] [4:6] [3:6] [4:6] [3:6] [3:6] [6:6] [5:6] [5:6] [4:6]

Off-site drift, low boom, 

tolerant plants

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

[6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [5:6] [4:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6] [6:6]

Off-site drift, backpack 

directed foliar, susceptible 

plants

0

[5:6]

0

[4:6] NE NE NE NE L[3:6]

M

[3:6]

L

[3:6]

L

[4:6]

M

[3:6]

M

[4:6] NE NE M

[3:6]

M

[4:6]

0

[4:6]

0

[4:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

Off-site drift, backpack 

directed foliar, tolerant 

plants

0

[6:6]

0

[6:6] NE NE NE NE 0[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6] NE NE 0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

0

[6:6]

Surface runoff, susceptible 

plants

0 0 0 0 0 0 0 0 0 0 H H 0

[21:30]

0

[18:30] H H L M 0 0 0 0

[22:30] [21:30] [23:30] [22:30] [22:30] [22:30] [18:30] [17:30] [18:30] [17:30]

Surface runoff, tolerant 

plants

0 0 0 0 0 0 0 0 0 0 L M0 0 0 0 0 0 0 0 0 0

[30:30] [29:30] [30:30] [28:30] [30:30] [30:30] [22:30] [22:30] [25:30] [22:30] [30:30] [30:30]

Aquatic Plants

Accidental spill, susceptible 

macrophytes H H H H NE NE H H NE NE H H H H NE NE H H NE NE NE NE

Accidental spill, susceptible 

algae H H L L H H H H H H L L M H H H H H H H M M

Accidental spill, tolerant 

algae L M 0 0 0 L M M H H 0 0 L M 0 0 M H L L M M

Acute exposure, susceptible 

macrophytes M M 0 0 NE NE L L NE NE M H L L NE NE 0 L NE NE NE NE

Acute exposure, susceptible 

algae L L 0 0 0 L L L H H 0 0 0 0 L L M H M M 0 0

Acute exposure, tolerant 

algae 0 0 0 0 0 0 0 0 L M 0 0 0 0 0 0 0 0 0 0 0 0

Chronic exposure, susceptible 

macrophytes 0 L 0 0 NE NE 0 0 NE NE M M 0 0 NE NE H H NE NE NE NE

Chronic exposure, susceptible 

algae 0 0 0 0 0 0 0 0 M M 0 0 0 0 0 0 0 0 L M 0 0

Chronic exposure, tolerant 

algae 0 0 0 0 0 0 0 0 0 L 0 0 0 0 0 0 0 0 0 0 0 0

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (HQ < LOC); L = Low risk (HQ = 1 to 10 x LOC); M = Moderate Risk (HQ = 10 to 100 x LOC); H = High risk (HQ > 100 LOC); and NE = Not evaluated. Risk categories are based on upper estimates of 

hazard quotients and the LOC of 1.0. If more than one scenario is involved in an exposure pathway (i.e., off-site drift and surface runoff), then the number of scenarios with the given risk category (out of the total number 
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216

of evaluated scenarios) is displayed in parentheses. The reported risk category is that of the majority of the HQs for all the scenarios. As a result, risk may be higher than the reported risk category for some scenarios within 

each category. For more information, see the individual Forest Service Risk Assessments.

2. In the 2010 FEIS, 2,4-D maximum risk ratings were calculated at 4 lbs./acre, although the FEIS stated that the BLM maximum rate was 1.9 lbs./acre. The risk ratings in this table reflect a maximum rate of 1.9 lbs./acre.

3. Glyphosate, imazapyr, picloram, and triclopyr Risk Assessments were updated in 2011. The risk ratings in this table reflect these 2011 Risk Assessments and may differ from the risk ratings shown in the 2010 FEIS.

4. Risk categories for the more toxic formulations are presented here.

5. Typ = Typical application rate; and Max = Maximum application rate.

6. Taken from scoping/screening level Risk Assessment Final Report (SERA 2014).

Table F-7. Forest Service-Evaluated Herbicide Risk Categories1 for Wildlife, Fish, and Aquatic Species

Scenario 2,4-D2,4 Clopyralid Dicamba Glyphosate3,4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.376 Typ Max

Mammals

Acute/Accidental Exposures

Direct spray, small mammal, 1st order 

absorption 01 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Direct spray, small animal, 100% 

absorption L L L L 0 0 0 L L L 0 0 0 L 0 0 0 L 0 0 0 0

Consumption of contaminated fruit, 

small mammal L L 0 0 0 L 0 L 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Consumption of contaminated grass, 

large mammal L L L L L M L L L L 0 0 0 L 0 0 M H 0 0 0 0

Consumption of contaminated water, 

small mammal, spill 0 0 0 0 0 L 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Consumption of contaminated water, 

small mammal, stream NE NE 0 0 0 0 NE NE 0 0 NE NE 0 0 NE NE NE NE 0 0 0 0

Consumption of contaminated insects, 

small mammal L L L L L M L L L L 0 0 0 L 0 0 0 L 0 0 0 0

Consumption of contaminated small 

mammal, predatory mammal L L 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Chronic Exposures

Consumption of contaminated 

vegetation, small mammal, on- site M M 0 0 0 0 L L 0 0 0 0 0 0 L M L M L M 0 0

Consumption of contaminated 

vegetation, small mammal, off- site NE NE 0 0 0 0 NE NE 0 0 NE NE 0 0 NE NE NE NE NE NE NE NE

Consumption of contaminated 

vegetation, large mammal, on- site L L 0 L 0 0 0 0 L M 0 0 0 0 0 L M H L L 0 0

Consumption of contaminated 

vegetation, large mammal, off -site NE NE 0 0 0 0 NE NE 0 0 NE NE 0 0 NE NE NE NE NE NE NE NE

Consumption of contaminated water, 

small mammal 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Birds

Acute/Accidental Exposures
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Scenario 2,4-D2,4 Clopyralid Dicamba Glyphosate3,4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.376 Typ Max

Consumption of contaminated grass, 

large bird 0 0 0 L L M 0 L L L 0 0 0 0 0 0 L M 0 0 0 0

Consumption of contaminated insects, 

small bird 0 L 0 L L M 0 L L L 0 0 0 0 0 0 L M 0 0 0 0

Consumption of contaminated small 

mammal, predatory bird 0 0 0 0 0 0 0 L 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Consumption of contaminated fish, 

predatory bird, spill 0 0 0 0 0 0 0 L 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Chronic Exposures

Consumption of contaminated 

vegetation, large bird, on-site 0 0 0 L 0 0 L L 0 0 0 0 0 0 0 L L M L M 0 0

Consumption of contaminated 

vegetation, large bird, off-site NE NE 0 0 0 0 NE NE 0 0 NE NE 0 0 NE NE NE NE NE NE 0 0

Consumption of contaminated fish, 

predatory bird 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0

Aquatic Species

Acute/Accidental Exposures

Fish (susceptible species7) – accidental 

spill H H L L 0 L H H L L 0 L 0 L M M H H M M L L

Fish (tolerant species) – accidental spill L L 0 0 0 0 M H 0 L NE NE 0 0 0 L M H M M L L

Fish (susceptible species) – acute 

exposure, peak EEC L L 0 0 0 0 L M 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Fish (tolerant species) – acute exposure, 

peak EEC 0 0 0 0 0 0 0 L 0 0 NE NE 0 0 0 0 0 0 0 0 0 0

Aquatic invertebrates – accidental spill 0 0 L M L M M M L L 0 0 0 0 0 0 L M L L L L

Aquatic invertebrates – acute exposure, 

peak EEC 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Chronic Exposures

Fish – chronic exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NE NE NE NE

Aquatic invertebrates – chronic 

exposure

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NE NE

Insects

Acute Exposures

Direct spray, bee, 100% absorption L L 0 L NE NE NE NE L L NE NE 0 0 NE NE NE NE NE NE NE NE

Consumption of fruit by a herbivorous 

insect NE NE NE NE NE NE 0 0 NE NE 0 0 NE NE 0 0 0 0 0 0 NE NE

Consumption of broadleaf/small Insects 

by a herbivorous Insect NE NE NE NE NE NE L L NE NE 0 0 NE NE 0 0 0 L 0 0 NE NE
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Scenario 2,4-D2,4 Clopyralid Dicamba Glyphosate3,4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.376 Typ Max

Consumption of short grass by a 

herbivorous insect NE NE NE NE NE NE L L NE NE 0 0 NE NE 0 0 0 L 0 0 NE NE

Consumption of tall grass by a 

herbivorous insect NE NE NE NE NE NE L L NE NE 0 0 NE NE 0 0 0 L 0 0 NE NE

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (HQ < LOC); L = Low risk (HQ = 1 to 10 x LOC); M = Moderate risk (HQ = 10 to 100 x LOC); H = High risk (HQ > 100 LOC); and NE = Not evaluated. Risk categories are based on upper estimates of 

hazard quotients and the BLM LOCs of 0.1 for acute scenarios and 1.0 for chronic scenarios. The reader should consult the text of this section of the individual Forest Service Risk Assessments to evaluate risks at central 

estimates of hazard quotients.

2. In the 2010 FEIS, 2,4-D maximum risk ratings were calculated at 4 lbs./acre, although the FEIS stated that the BLM maximum rate was 1.9 lbs./acre. The risk ratings in this table reflect a maximum rate of 1.9 lbs./acre.

3. Glyphosate, imazapyr, picloram, and triclopyr Risk Assessments were updated in 2011. The risk ratings in this table reflect these 2011 Risk Assessments and may differ from the risk ratings shown in the 2010 FEIS.

4. Risk levels for the more toxic formulations are presented here.

5. Typ = typical application rate; and Max = maximum application rate.

6. Taken from scoping/screening level Risk Assessment Final Report (SERA 2014).

7. Fish susceptible species include coldwater fish, such as trout, salmon, and federally listed species. Fish tolerant species include warm water fish, such as fathead minnows.

Table F-8. Forest Service-Evaluated Herbicide Risk Categories1 for Human Health

Scenario 2,4-D2,4 Chlorsulfuron Clopyralid Dicamba Glyphosate3,4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.3756 Typ Max

Workers

General Exposures

Directed foliar and spot treatments 

(backpack) L1 L 0 0 0 0 0 0 0 0 0 L 0 0 0 0 0 0 0 L 0 0 0 0

Broadcast ground spray (boom 

spray) L L 0 L 0 0 0 L 0 0 0 L 0 0 0 0 0 0 0 L 0 0 0 0

Aquatic applications L L NE NE NE NE NE NE 0 0 0 NE 0 0 NE NE NE NE NE NE NE NE NE NE

Accidental/Incidental Exposures

Immersion of hands 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Wearing contaminated gloves M M 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Spill on hands 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Spill on lower legs 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Public

Acute/Accidental Exposures

Direct spray - child, entire body 0 L 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Direct spray - woman, lower legs 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Dermal - contaminated vegetation, 

woman 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Consumption of contaminated fruit 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Consumption of contaminated 

water - pond, spill NE NE 0 0 0 L 0 L NE NE 0 0 NE NE 0 0 NE NE NE NE NE NE NE NE
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Scenario 2,4-D2,4 Chlorsulfuron Clopyralid Dicamba Glyphosate3,4 Hexazinone Imazapyr3 Metsulfuron 

methyl Picloram3 Triclopyr3,4 Fluazifop-Pbutyl6 Sethoxydim

Typ5 Max5 Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max Typ Max 0.16 0.3756 Typ Max

Consumption of contaminated 

water - stream, ambient NE NE 0 0 0 0 0 0 NE NE 0 0 NE NE 0 0 NE NE NE NE NE NE NE NE

Consumption of contaminated 

water - child 0 0 NE NE NE NE NE NE 0 L NE NE 0 0 NE NE 0 0 0 L 0 0 0 0

Consumption of contaminated fish 

- general public 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Consumption of contaminated fish 

- subsistence populations 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0

Chronic/Longer-term Exposures

Consumption of contaminated fruit 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 L 0 0 0 0

Consumption of contaminated 

water

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Consumption of contaminated fish 

- general public 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Consumption of contaminated fish 

- subsistence populations 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Shading denotes herbicides that are limited by Mitigation Measures to typical application rates where feasible.

1. Risk categories: 0 = No risk (majority of HQs < 1); L = Low risk (majority of HQs >1 but < 10); M = Moderate risk (majority of HQs > 10 but < 100); H = High risk (majority of HQs > 100); and NE = Not evaluated. Risk 

categories are based on central HQ estimates. To determine risk for lower or upper HQ estimates, see the individual herbicide Risk Assessments. Risk categories are based on comparison to the HQ of 1 for typical and 

maximum application rates.

2. In the 2010 FEIS, 2,4-D maximum risk ratings were calculated at 4 lbs./acre, although the FEIS stated that the BLM maximum rate was 1.9 lbs./acre. The risk ratings in this table reflect a maximum rate of 1.9 lbs./acre.

3. Glyphosate, imazapyr, picloram, and triclopyr Risk Assessments were updated in 2011. The risk ratings in this table reflect these 2011 Risk Assessments and may differ from the risk ratings shown in the 2010 FEIS.

4. Where different formulations exist, risks reported are the most conservative.

5. Typ = Typical application rate; and Max = Maximum application rate.

6. Taken from scoping/screening level Risk Assessment Final Report (SERA 2014).
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Appendix G: Issues Not Analyzed in Detail

220 

Appendix G: Issues Not Analyzed in 

Detail

Several issues identified during internal and external scoping were considered but not analyzed in detail in this EA. 

Issues are not analyzed in detail if:

• the issue does not respond to the purpose and need; 

• there is no potential for significant effects related to the issue; or,

• the issue has already been appropriately analyzed in documents to which this EA tiers. 

Issues analyzed in detail (Issues 1, 2, and 3) are included in Chapter 3.

Issue 4 (Native Vegetation): What are the effects of invasive plant 

treatments on desirable plant communities and Special Status plants?

The BLM received comments raising the concern of how other plants would be impacted by invasive plant 

treatments. Some comments expressed specific concerns related to herbicides and non-target plants (including 

rare plants) and effects to forest health. To consider this issue, the BLM looked at how the invasive plant program 

impacts native plant communities, Special Status plants, and forest health. 

The effects of non-herbicide treatment methods on native plants are not analyzed in detail because they were

adequately analyzed in the Northwest Area Noxious Weed Control Program Final EIS and Supplement (USDI 1985, 

1987a) to which this EA tiers. Similar to the Vegetation Treatments Programmatic Environmental Report, that EIS 

describes that some injury or loss of non-target vegetation would occur but that, in the long-term, non-target 

species will become reestablished (USDI 1985:12, 40). The effects of most of the herbicides (i.e., all herbicides 

except sethoxydim and District-wide use of fluazifop-P-butyl) on native vegetation are not analyzed in detail 

because these effects were analyzed in NEPA analyses to which this EA tiers: the 2007 and 2016 PEISs (done at the 

national level), the 2010 Oregon FEIS, and the EIS done for the West Eugene Wetlands Resource Management Plan 

(USDI 2010a:139-155, USDI 2007a:4-44 to 4-76, USDI 2016a:4-25 to 4-41, USDI 2015a:172-187). There are no new 

circumstances or information at the District level that would change the effects anticipated for this EA. Application 

of fluazifop-P-butyl and sethoxydim would be highly limited in areal extent, consistent with Research and 

Demonstration purposes of application. Given the limited areas that they would be used in and their selectivity to 

grasses, there would be no potential for significant adverse effects.

As described in the Oregon FEIS, the Northwest Oregon District is composed of two biomes33, the Western Forest 

Biome (including the Western Cascades and Oregon Coast Range) and the Willamette Valley Biome. The Western 

Forest Biome is dominated by dense conifer forests. The biome also includes sand dunes, meadows, marshes, 

bogs, rock outcrops, and woodlands. Dense shade producing forests are the least likely areas to provide 

opportunities for sun loving invasive plants to establish (Quigley and Arbelbide cited in USDI 2010a:140), but some 

species such as English ivy, false brome, garlic mustard, and blackberry have adversely affected native species in 

this biome. A 2008 forest inventory showed 47 percent of plots in the Oregon Coast Range and 68 percent of plots 

in the Western Cascades (across all ownerships) had invasive plants present, and 6.2 percent of all plant cover in 

forests was easily identifiable non-native weeds (Donnegan et al. 2008 cited in USDI 2010a:140). The Willamette 

Valley biome was historically dominated by native oak woodlands, oak savannahs, and upland or wet prairies. 

These areas have been largely transformed by cultivation, timber harvest, development, and invasive plants. With 

 

33 Areas with similar climatic conditions, geomorphology, and soils, which influences the composition and functioning of 

vegetative communities.
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only remnant populations of native plants remaining, many unique Willamette Valley plant communities are 

imperiled (USDI 2010a:140).

There are 105 Special Status plants documented on the District, including 60 vascular plants, 16 liverworts, 13 

mosses, and 16 lichens (USDA and USDI 2015). This includes four federally listed vascular plants. Special Status 

plants occur in a variety of habitats on the District, including open meadows, old growth forest, and aquatic 

systems. These rare species display narrow ecological amplitudes and are geographically restricted, making them 

particularly vulnerable to degradation from invasive plants (USDI 2010a:149). There are 58 Special Status plant

species that are within 100 feet of an invasive plant species on 416 sites. Populations threatened by invasive plant 

infestations include three federally listed species: Willamette valley daisy, Bradshaw's lomatium, and Kincaid's 

lupine. As described in the Oregon FEIS, loss of native plant communities in the Willamette Valley biome has led to 

the Federal listing of Kincaid’s lupine, golden paintbrush (suspected but not documented on the District), and 

Willamette Valley daisy (USDI 2010a:140). Invasive plants also contributed to the listing of Bradshaw’s lomatium 

and Nelson’s checkermallow.

As described in the Oregon FEIS, invasive plant treatments on the District would primarily benefit native vegetation 

in the long-term. Treatments would result in a short-term loss of native vegetation, but the long-term effects of 

these treatments are expected to benefit native ecosystems, as treatments reduce the density and distribution of 

invasive plant species. Invasive plant invasions displace native plants, adversely affecting the composition and 

structure of the plant community and thus the other elements of the ecosystem that are dependent on it. The 

Oregon FEIS lists the other effects of invasive plants on native plant communities including increased competition, 

decreased species diversity, and reduced structural complexity (USDI 2010a:148-149). The Oregon FEIS described 

that with limited treatment options and invasive plant species without effective treatment methods, native plant 

communities will suffer loss of native species and alteration of community function in the long term almost 

regardless of the level of effort or priority given to their consideration (USDI 2010a:152). The effectiveness of the 

treatment programs under each alternative on managing invasive plant populations is analyzed in detail in Chapter 

3 (see Issue 1).

Although the protection of sites known to be occupied by Special Status species is a priority for BLM weed control 

efforts, success of those efforts will vary depending upon the likelihood of those sites being invaded and whether 

effective weed treatment tools are available (USDI 2010a:149). As described in the Oregon FEIS, there would be no 

potential for treatments of invasive plants to cause a significant effect to Special Status plants. Projects that have 

the potential to disturb Special Status plants and plant habitat require pre-project clearances, including review for 

potential habitat and surveys in suitable habitat to identify populations and necessary protection measures34 (USDI 

2010a:142-144). 

The Oregon FEIS showed that the direct effects of invasive plant treatments on forest health, whether 

accomplished with herbicide or non-herbicide methods, are expected to be negligible (not be detectable or 

measurable). Though invasive plant treatments would be implemented to control the spread of invasive plants and 

not for the purpose of timber production, indirect effects of invasive plant treatments to timber production would 

be positive as invasive plants that compete with desirable conifers are removed (USDI 2010a:280). Treatments on 

invasive plants are generally focused on specific plants, and collateral damage to crop trees is rare (USDI 

2010a:280). Invasive plants such as Scotch broom can populate a recently harvested site more quickly than native 

species and will compete with desired conifers if left untreated. While this results in decreased timber growth, the 

effects are gradual; current silvicultural methods are already dealing with some level of invasive plants. Yield 

predictions are based in part on the performance of existing stands, and quantifying the growth loss from the 

current or future percentage of invasive plants has not been done (USDI 2010a:281). 

 34 For example, using spray shields, buckets, or tarps to protect nearby plants from drift during herbicide application.
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The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the EISs to which this analysis tiers. All Standard Operating Procedures and Mitigation Measures analyzed in those 

documents would be applied to all alternatives. 

Issue 5 (Fungi): How would invasive plant treatments affect fungi?

The BLM received a comment raising a concern about the potential for invasive plant treatments, especially 

herbicides, to harm fungi. This issue is not analyzed in detail because this issue has already been adequately

analyzed in documents to which this EA tiers and there is no potential for significant effects.

There are a variety of fungi on the District including edible fungi (such as chanterelles, matsutakes, hedgehogs, 

oysters, morels, and king boletes) that are collected by the public and 24 Special Status fungi. Treatment methods 

that have the potential to impact fungi include manual methods, prescribed fire, and some herbicides. As 

described in the Oregon FEIS, 2,4-D, triclopyr, sulfometuron methyl, and glyphosate have been shown to inhibit 

the growth of fungi in laboratory experiments (USDI 2010a:144-147), although in studies using similar rates or

amounts proposed for use on BLM-administered lands, fungi seemed unimpacted (USDI 2010a:144). Manual 

treatment methods could have the potential to affect fungi due to the potential to disturb the mycelia (the 

underground body of the fungi). However, there would be no potential for effects due to spatial differences. As 

described in the Oregon FEIS, invasive plant treatments in forest habitat would be primarily accomplished along 

rights-of-way, rather than healthy forests where species are dependent on the roots (ectomycorrhizae) of conifer 

trees (USDI 2010a:145). Fire has been shown to promote the fruiting of some fungi species, but prescribed fire 

used as an invasive plant treatment is not expected to affect mycelia; prescribed fires burn at lower temperatures 

than wildfires that would harm mycelia. 

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the EISs to which this analysis tiers. All Standard Operating Procedures and Mitigation Measures analyzed in those 

documents would be applied to all alternatives. 

Issue 6 (Wildlife): How would integrated invasive plant management 

affect wildlife of conservation concern? 

The BLM received several comments expressing concern about the potential for adverse effects from invasive 

plant treatments (especially herbicides) to wildlife. To consider this issue, the BLM looked at the program's effects 

on wildlife of conservation concern as representative species that have the potential to be affected by invasive 

plant treatments. Wildlife of conservation concern, for the purposes of this analysis, include Special Status wildlife 

species, bald and golden eagles, U.S. Fish and Wildlife Service Birds of Conservation Concern (USDI 2008e), 

Partners in Flight Species of Continental Concern (Rosenberg et al. 2016), and big game.

This issue is not analyzed in detail because the effects of the herbicides on wildlife were adequately analyzed in 

three NEPA analyses to which this EA tiers: the 2007 and 2016 PEISs (done at the national level) and the 2010 

Oregon FEIS (USDI 2010a:241-257, USDI 2007a:4-96 to 4-113, USDI 2016a:4-51 to 4-64). The effects of nonherbicide methods were previously described in the Northwest Area Noxious Weed Control Program Final EIS and 

Supplement (USDI 1985:43-47, 1987a) to which this EA tiers.

There are no new circumstances or information at the District level that would change the effects anticipated for 

this EA. The herbicides analyzed in this EA were chosen in part because they were unlikely to have adverse effects 

to wildlife (Appendix C and USDI 2010a:245) and Mitigation Measures adopted with the Records of Decision for 

these three EISs mitigated all potentially significant effects at the national and state level. 
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The Northwest Oregon District manages approximately 714,000 acres of land with a wide variety of habitats 

including forest, meadows, dunes, oak woodlands, pine savannas, marshes, and streams. These habitats support a 

rich diversity of wildlife species. While some wildlife would benefit from or tolerate invasive plants (e.g. American 

black bear consuming Himalayan blackberry fruit), invasive plants seldom provide the same food and cover quality 

as native species (USDI 2010a:251). The International Union for the Conservation of Nature ranks invasive species 

as one of the top 10 threats to currently threatened species (IUCN 2008 cited in USDI 2010a:251). The Oregon FEIS 

notes that native bird diversity corresponds with native plant diversity, invasive plants can crowd out amphibians, 

and many invasive plants are unpalatable to wildlife species (USDI 2010a:251-253). Native insects, especially 

Special Status insects and native pollinators, tend to prefer native species and are generally adversely affected by 

invasive plants (USDI 2010a:241-242). The Oregon FEIS concludes that long-term beneficial effects to native 

wildlife populations occur with treatment of invasive plants as adverse habitat changes can result from invasive 

plants (USDI 2010a:252).

Under all alternatives, the type of actions and the amount of treatments are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2007 and 2016 PEISs. All Standard Operating Procedures and Mitigation Measures 

analyzed in those documents would be applied to all alternatives. Under the action alternatives, 95 percent of 

herbicide treatments on the Northwest Oregon District would be spot treatments to target specific plants, which 

would minimize effects to non-target species, including wildlife. Standard Operating Procedures and Mitigation 

Measures including limitations on the herbicide active ingredients and doses, handling procedures, application 

methods, drift minimization, and timing of application are designed to greatly reduce the likelihood that the 

modeled exposure scenarios described would actually occur, and thus reduce the potential for adverse effects to 

wildlife species, including Special Status species. Effects to birds and pollinators are further described in Issues 7 

and 8, respectively.

Issue 7 (Birds): How would treatments affect birds that may use 

potential treatment areas, especially during the nesting season?

The BLM received two comments expressing concern about invasive plant treatments disturbing birds. This issue is 

not analyzed in detail because these effects were adequately analyzed in the 2010 Oregon FEIS (USDI 2010a: 253-

254) and the Proposed Resource Management Plan and Final Environmental Impact Statement for the Bureau of 

Land Management West Eugene Wetlands Resource Management Plan (USDI 2015a:85, 157). There are no new 

circumstances or information at the District level that would change the effects anticipated for this EA. The type of 

actions and the amount of treatments under all alternatives are wholly within the actions analyzed in the 2010 

Oregon FEIS and the analysis for the West Eugene Wetlands Resource Management Plan.

The Oregon FEIS determined that birds would avoid the treatment area during treatment because of noise and 

activity (USDI 2010a:253-254). As described in the Oregon FEIS, disturbance may disrupt normal behavior to the 

extent that survival of adults is impaired or reproduction compromised. Effects would depend on the intensity of 

disturbance, extent of habitat affected, duration of the activity, and whether the activity occurs during a 

vulnerable time such as when the animal is restricted to a nest, breeding area, or winter range (USDI 2010a:253). 

Associated with herbicide application, animals that temporarily leave the treatment area have reduced risk of 

directly ingesting the herbicide while grooming or from ingesting herbicides on vegetation or prey (insects or other 

animals that were directly sprayed). Some pre-fledgling birds could be restricted to the treatment area and could 

be adversely affected by broad scale treatments using herbicides with moderate toxicity35 (USDI 2010a:246-250). 

However, herbicide treatments on the Northwest Oregon District are done with hand-directed sprayers and 

applied selectively (i.e. treatments are not broad scale) and are not likely to result in such a direct spray scenario. 

The 2016 PEIS identified no risk to birds from the use of aminopyralid, fluroxypyr, or rimsulfuron under any 

scenario at either the typical or maximum rates.

 

35 Triclopyr, 2,4-D, and dicamba at the maximum rate have a moderate risk to birds in certain Risk Assessment scenarios; all 

other scenarios are low or no risk. See Appendix F, Herbicide Risk Assessment Summaries. 
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Specific to nesting birds, the Oregon FEIS found that the potential for adverse effects from treatment methods 

(including non-herbicide treatment methods) is also minimized by the following Standard Operating Procedure:

• Minimize treatments during nesting and other important periods for birds and other wildlife.

The federally threatened streaked horned lark inhabits flat (less than 5 percent slope), treeless landscapes with 

sparsely vegetated ground cover of at least 300 acres in size or with visual access to open water or fields (USDI 

2013b). Short-statured grasses and forbs are important habitat elements for horned larks. Control of invasive 

plants would benefit streaked horned lark, as this would increase the amount of short-statured native (as opposed 

to tall-statured non-native) grasses and forbs. Streaked horned larks occur at the West Eugene Wetlands, and no 

other habitat for the species occurs on the District. The effects of integrated vegetation management on this 

species is not analyzed in detail because effects would be consistent with the analysis in the FEIS for the Proposed 

Resource Management Plan and Final Environmental Impact Statement for the Bureau of Land Management West 

Eugene Wetlands Resource Management Plan (USDI 2015a:85, 157). The additional herbicides that would be 

authorized for use under the action alternatives are not expected to affect the streaked horned lark any differently 

than the herbicides already used in the species’ habitat under the No Action Alternative. 

The action alternatives are not expected to adversely affect the marbled murrelet or the northern spotted owl

because proposed invasive plant treatments would not modify habitat and would not affect the northern spotted 

owl or marbled murrelet’s prey species. Disturbance near nest sites of either species is not anticipated because 

projects are usually short in duration, spatially limited, and affected areas receive baseline disturbance from 

vehicle traffic and other activities. Northern spotted owls and marbled murrelets would likely be acclimated to the 

level of noise disturbance that BLM expects invasive plant treatments to generate. 

Issue 8 (Pollinators): How would herbicide treatments affect 

pollinators, especially Special Status pollinator species?

The BLM received two comments expressing concern about herbicides harming rare pollinators. This issue is not 

analyzed in detail because the effects of the herbicides on wildlife were adequately analyzed in four NEPA analyses 

to which this EA tiers: the 2007 and 2016 PEISs, the 2010 Oregon FEIS, and the Proposed Resource Management 

Plan and Final Environmental Impact Statement for the Bureau of Land Management West Eugene Wetlands 

Resource Management Plan (USDI 2010a:241-257, USDI 2007a:4-96 to 4-113, USDI 2016a:4-51 to 4-64, USDI 

2015a:174). There are no new circumstances or information at the District level that would change the effects 

anticipated for this EA.

Seven Special Status wildlife species serve as pollinators on the Northwest Oregon District: the western 

bumblebee, and six butterflies. The Oregon FEIS explains that adult honeybees were used as a surrogate for all 

invertebrates in Risk Assessments. The Risk Assessments (see Appendix F) indicate that there is low risk to 

honeybees or other insects in direct spray or vegetation consumption scenarios involving 2,4-D, clopyralid, 

fluroxypyr, glyphosate, hexazinone, and triclopyr at typical (fluroxypyr, glyphosate, and hexazinone) or maximum 

(clopyralid and triclopyr) rates and no risk from all other herbicides evaluated in this EA. 

As described in the Proposed Resource Management Plan and Final Environmental Impact Statement for the 

Bureau of Land Management West Eugene Wetlands Resource Management Plan, several biological opinions from 

the U.S. Fish and Wildlife Service articulate the appropriateness and efficacy of fluazifop-P-butyl use for prairie 

restoration in the Willamette Valley, especially in and around Fender’s blue butterfly sites. Research and 

Demonstration use would help the BLM evaluate the effectiveness of fluazifop-P-butyl in controlling non-native 

grasses in prairie restoration without adversely affecting native prairie plant species such as the host and nectar 

plants of Fender’s blue butterflies (USDI 2015a:174). 
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The 2016 PEIS states that treatments that remove non-native plant species that inhibit the growth of native plant

species used by pollinators or limit native forb diversity would be expected to benefit pollinators. The PEIS cites 

Federal guidance identifying the removal of invasive species as an effective way to increase pollinator abundance 

and diversity (USDI 2016a:4-54). Neither aminopyralid nor rimsulfuron, analyzed in the 2016 PEIS, were shown to 

have any risk under any of the modeled exposure scenarios to pollinators (USDI 2016a:4-56). Habitat modification 

is often the main risk to wildlife (including pollinators) from herbicide use and occurs in the short term, but in 

general the long-term effects of more effective methods to remove invasive plants would improve wildlife habitat 

(USDI 2016a:4-54-56).

The alternatives would conform with recommendations from the 2014 Presidential Pollinator Task Force; Standard 

Operating Procedures and Mitigation Measures for pollinators outlined in Appendix D conform to the National 

Strategy to Promote the Health of Honey Bees and Other Pollinators. Conservation Measures were identified in the 

2007 and 2016 Biological Assessments for Special Status species, including the following for Special Status insect 

pollinators:

● Do not use 2,4-D in TEP36 butterfly/moth habitat.

● When conducting herbicide treatments in or near habitat used by TEP butterflies or moths, avoid use of 

the following herbicides, where feasible: clopyralid, glyphosate, imazapyr, picloram, and triclopyr.

● If conducting manual spot applications of glyphosate, or triclopyr to vegetation in TEP butterfly or moth 

habitat, utilize the typical, rather than the maximum, application rate.

Herbicide use may inadvertently cause the short-term damage of Oregon sunshine and other common nectar 

sources of Fender’s blue butterfly, Taylor’s checkerspot, and Oregon silverspot. It may also cause short-term 

damage to host plants37 of these species (e.g., sickle-keeled lupine is a common native species and serves as a host 

plant for Fender’s blue butterfly). As treatments would reduce the prevalence of invasive plant species, which are a 

major threat to all listed butterflies (USDI 2010e), such treatments would have long-term benefits to listed 

butterflies. BLM is consulting with the U.S. Fish and Wildlife Service on the effects of these five chemicals on listed

butterflies. BLM will adopt any additional Project Design Criteria that result from this consultation. 

The Risk Assessment indicates that fluroxypyr has a low risk under typical and maximum rates to susceptible 

pollinating insects under the 100 percent absorption scenario (direct spray). Therefore, the following Mitigation 

Measure adopted with the 2016 PEIS would also be applied to treatments on the Northwest Oregon District:

• When conducting herbicide treatments in or near habitats used by Special Status and listed terrestrial 

arthropods, design treatments to avoid the use of fluroxypyr, where feasible. If pre-treatment surveys 

determine the presence of listed terrestrial arthropods, do not use fluroxypyr to treat vegetation.

In addition, the following Project Design Feature provides additional protections to other pollinators of 

conservation concern:

• Apply Conservation Measures applicable to butterflies and moths, as appropriate, for other Bureau 

Sensitive terrestrial invertebrates.

Issue 9 (Turtles): How would the treatment of aquatic invasive plants 

affect the western pond turtle and painted turtle?

The BLM received two comments expressing concern about the effects of invasive plant treatments to aquatic 

wildlife. Aquatic wildlife species other than turtles are addressed in Issue 2 (see Chapter 3). This issue is not 

analyzed in detail; the effects of the herbicides on turtles were adequately analyzed in three NEPA analyses to 

which this EA tiers: the 2007 and 2016 PEISs (done at the national level) and the 2010 Oregon FEIS (USDI 

2010a:241-257, USDI 2007a:4-96 to 4-113, USDI 2016a:4-51 to 4-64). 

 

36 Federally listed as threatened or endangered, or proposed for such listing. 37 A plant upon which an organism (such as an insect) lodges and subsists.
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Effects of non-herbicide treatments are not analyzed in detail because there is no potential for significant effects.

As described in Issue 2 (see Chapter 3), most manual and mechanical methods would cause temporary 

disturbances, but fauna would quickly return to the area. However, painted and western pond turtles often 

estivate at the bottom of ponds when temperatures are too hot (between mid-July and mid-August) or too cold 

(after mid-September to the start of May). The following Project Design Feature minimizes the potential for 

bottom barriers / weed mats to suffocate turtles and suction harvest/tractors to physically harm or kill individuals:

• Survey for western pond turtles and painted turtles before applying bottom barriers / weed mats or diverassisted suction harvest/tractors in the habitat of these species38 (e.g., ponds and streams/rivers with 

pools and/or coves). If either species is present, restrict these types of treatments to only occur between 

May 7 and July 15 or between August 15 and September 15.

Western pond turtles and painted turtles are Bureau Sensitive species that would benefit from treatments of 

aquatic invasive plant species under Alternative 3. Western pond turtles are not likely to inhabit ponds that are 

heavily infested with parrot feather or other aquatic invasive plants that form contiguous mats of vegetation (Chris 

Yee, Oregon Department of Fish and Wildlife Assistant District Wildlife Biologist, 2018 personal communication). 

Treatments are expected to improve habitat diversity to support various life stages and increase oxygen levels in

turtle habitat.

Issue 10 (Fish and Aquatic Organisms): What are the effects of 

terrestrial herbicide treatments along streams to fish and aquatic 

organisms?

The BLM received comments raising the concern about what herbicide treatments along streams might do to fish 

and aquatic organisms. To consider this issue, the BLM looked at the invasive plant program within the riparian 

area (150 to 220 feet from waterbodies). 

This issue was not analyzed in detail because there is no potential for significant effects to fish and aquatic 

organisms beyond the effects of herbicides that were described in the NEPA analyses to which this EA tiers; the 

2007 and 2016 PEISs and the 2010 Oregon FEIS (USDI 2010a:208-240, USDI 2007a:4-36 to 4-4-96, USDI 2016a:4-41 

to 4-51). The nature of the disturbance associated with terrestrial invasive plant treatments would not affect fish 

and other aquatic organisms, including those that are federally listed or Bureau Sensitive, or their habitat in 

dispersed areas across the District in any given year. Depending on the site, streamside treatments would remove 

invasive vegetation that often supports fewer native insects than native plant species, which could temporarily 

affect food availability for insectivorous fish species, such as salmonids (USDI 2010a:230). The BLM would apply 

herbicides consistent with the aquatic no-herbicide application buffers specified in the Aquatic Restoration 

Biological Opinion II (NMFS 2013) to all waterbodies with known or suitable habitat for Bureau Sensitive fish and 

other Bureau Sensitive aquatic species. The BLM would also confine the use of fluazifop-P-butyl to flat, dry ground 

located greater than 300 feet from any surface water connected to a stream network outside the West Eugene 

Wetlands. These actions are wholly within the actions evaluated in the EISs to which this EA tiers, and no new or 

changed circumstances apply to change the effects of those actions at the scale evaluated in this EA.

Issue 11 (Human Health): What are the effects to human health from 

incidentally coming into contact with herbicides used on BLMadministered lands?

The BLM received several comments expressing concern that human health would be adversely affected by 

herbicide use. These comments raised concern that the recreating public could inadvertently be harmed, but also 

 

38 This can be identified during the interdisciplinary team review of the Annual Treatment Plan.
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expressed concern that more susceptible populations (including children, pregnant women, the elderly, sick 

people, and those with chemical-sensitive conditions) or populations that regularly consumed or came into contact 

with contaminated vegetation, water, or wildlife might be even more at risk. 

This issue was not analyzed in detail because effects were previously described in the analysis for the Oregon FEIS 

and the 2007 and 2016 PEISs (USDI 2010a:345-358, USDI 2007a:4-174 to 4-196, USDI 2016a:4-87 to 4-103) and 

there are no new circumstances or information at the District level that would change the effects anticipated for 

this EA.

The administrative boundaries of the Northwest Oregon District include the largest metropolitan areas (Portland, 

Eugene, and Salem) in Oregon. As described in Issue 25, over 2.5 million recreators visit the District’s recreation 

sites annually. As described in Issue 21, local Tribes have treaty rights on BLM-administered lands which allow 

them to hunt, fish, gather, and trap on the District, and other Tribes without specific off-reservation reserved 

rights gather natural resources for traditional or cultural purposes (USDI 2010a:284). People collect mushrooms 

and berries on BLM-administered lands and swim in streams and lakes.

Herbicides are formulated to affect plant growth; some mimic plant hormones (auxins), others affect 

photosynthesis, amino acid, or lipid synthesis, or disrupt cell membranes. While they are selective for plants, they 

have the potential to affect human health if used improperly (Appendix F and USDI 2010a:345). Exposure scenarios 

for human health effects for the public were analyzed in human health Risk Assessments for direct spray, dermal 

exposure from contaminated vegetation, consumption of contaminated water, acute exposure from spills, 

consumption of contaminated fish, and consumption of contaminated vegetation (USDI 2010a:347).

Tables G-1 and G-2 display a summary of information showing the herbicides that have risk (greater than 0) to the 

public in one or more Risk Assessment-modeled scenario. All other herbicides had no risk for any of the modeled 

scenarios of public exposure, including incidental handling, consumption, and contact with the skin. Human health 

Risk Assessments include scenarios that address subsistence populations and Native American populations (see 

Appendix F).

Table G-1. Human Health Herbicide Risk Summary, Public

Herbicides

Risk Category

(worst-case scenario, one or more scenarios) How Often Herbicide Would be Used

Typical 

rate

Maximum rate

Direct 

Spray

Dermal 

Exposure

Consumption of 

Contaminated Substance2 No Action Alternative Action Alternatives

2,4-D3 0 L1 01 01,2 <1% (Cascades Field Office) 5%4

Clopyralid 0 0 0 L (water) <1% (West Eugene Wetlands) 7%

Dicamba 0 0 0 L (water) 1% (Cascades Field Office) 5%

Fluazifop-P-butyl 0 0 0 L (fish) <1% (West Eugene Wetlands) <1%

Glyphosate3 0 0 0 L (water)

98% (Cascades, Tillamook, 

and Marys Peak Field Offices 

and West Eugene Wetlands)

19%

Triclopyr3 0 L1 L1 L1,2 (water and fruit) <1% (West Eugene Wetlands) 23%

1. Limited by Mitigation Measures to typical rate where feasible.

2. Contaminated vegetation, fruit, water, or fish. Consumption of contaminated mammals was not evaluated for human health; large 

mammalian carnivores had detectable risk in scenarios that involved 2,4-D (low at typical and maximum rates), triclopyr (low at maximum 

rates), and dicamba + diflufenzopyr (low at typical rate and moderate at maximum rate, under chronic exposure scenarios).

3. Where different formulations exist, risks reported are the most conservative.

4. 2,4-D would generally be used as part of a tank mix (to prevent resistance). 2,4-D by itself would be used less than 1 percent of the time.
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Table G-2. Summary of Effects of Herbicides1 on Human Health

Additional information about the risk ratings discussed below can be found in Appendix F, Herbicide Risk Assessment Summaries.

2,4-D 

The public faces zero risk from all modeled scenarios except one; there is low risk to a child being sprayed 

over their entire body at maximum application rate. In the human health Risk Assessment conducted to 

support the reregistration of 2,4-D (USEPA 2004), the EPA concluded that there is not sufficient evidence 

that 2,4-D is an endocrine disrupting chemical. 

Clopyralid The public faces zero risk from all modeled scenarios except one; there is low risk to the public from the 

consumption of water from a pond contaminated with a spill.

Dicamba The public faces zero risk from all modeled scenarios except one; there is low risk to the public from the 

consumption of water from a pond contaminated with a spill.

Fluazifop-PbutylThere is low risk to subsistence population consuming fish from fluazifop-P-butyl applications at the 

maximum rate after an accidental spill into a pond.

Glyphosate 

For both workers and members of the public, there are no risks associated with nearly all exposures to 

glyphosate at the typical or maximum application rate (SERA 2011a). The Risk Assessment calculated no risk 

for all but one of the tested scenarios. There is low risk to children associated with accidental exposure to 

glyphosate through consumption of contaminated water after an herbicide spill at the maximum rate into a 

small pond. See also Issue 14.

Triclopyr

There is low risk to the public from triclopyr BEE applications at the maximum rate under four acute or 

accidental scenarios: 1) direct spray to the lower legs; 2) dermal contact with contaminated vegetation; 3) 

acute consumption of contaminated fruit; and 4) acute consumption by a child of pond water contaminated 

by a spill. There is low risk to the public from triclopyr acid (TEA) applications at the maximum rate for acute 

consumption by a child of pond water contaminated by a spill, and for chronic consumption of contaminated 

fruit. 

1. Table does not include herbicides with no measurable risk. Herbicide information summarized from the 2010 Oregon FEIS (USDI 2010a:345-

358), the 2007 PEIS (USDI 2007a:4-174 to 4-196), the 2016 PEIS (USDI 2016a:4-87 to 4-103), and the fluazifop-P-butyl Risk Assessment (SERA 

2014).

Ratings are based on various exposure scenarios. Standard Operating Procedures and Mitigation Measures 

including limitations on the herbicide types and doses, handling procedures, application methods, drift 

minimization, and timing of application are designed to greatly reduce the likelihood that the modeled exposure 

scenarios described would actually occur, and thus reduce the described adverse effects. All of the herbicides

proposed for use in the action alternatives have zero risk at typical rates. As shown in Appendix C (Treatment Key), 

2,4-D, dicamba, and triclopyr would not be used at the maximum rates. However, clopyralid, fluazifop-P-butyl, and 

glyphosate would be used at the maximum rate for a few species. Specifically,

• Clopyralid would be used to control species in the hawkweed and Canada thistle species groups.

• Fluazifop-P-butyl would be used on perennial grasses.

• Glyphosate would be used on snapdragons, perennial peas, perennial grasses, perennial mustards, 

miscellaneous herbaceous (perennial and annual), and buttercup species groups.

The only scenarios with risk that are theoretically possible under the alternatives are associated with an accidental 

spill of herbicides into water:

• a low risk to the public from consuming clopyralid contaminated water after an accidental spill;

• a low risk to a subsistence population from eating contaminated fish after an accidental spill of fluazifopP-butyl; or,

• a low risk to a small child from consuming glyphosate contaminated water after an accidental spill.

As described in the 2010 Oregon FEIS, accidental spills directly into water are not expected to occur; targeted 

application methods and Protection Measures would prevent these scenarios from happening. Clopyralid and 

fluazifop-P-butyl are not registered for aquatic use and would be buffered from any waterbodies (see Appendix C 

for buffers).

The Oregon FEIS describes that the Risk Assessments apply uncertainty factors (multiplying the lowest observable 

effects by a factor of 10, 100, or even 1,000 to get a level of concern), which are included to account for 

hypersensitive individuals and otherwise accommodate uncertainties into the measurements. Thus, herbicide 

exposure of a healthy (not susceptible) individual to a dose identified as having a risk would likely have no effect. 
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Nevertheless, the low rating indicates that the potential for risk starts at that level of concern (USDI 2010a:91). The

Human Health sections of those Risk Assessments also include scenarios with children and women (see Appendix 

F, Herbicide Risk Assessment Summaries).

In addition, there would be no potential for effects due to spatial and temporal differences. Treatments in this EA 

are targeted towards invasive plants, which – with some exceptions – are not plant species being collected or

ingested. Triclopyr would be used on blackberry plants (and other woody species) on the District, applied via foliar, 

cut-stump, or basal spray methods at typical rates. However, while blackberries are widespread on the District, 

treatments typically happen when fruit is not present, either during the flowering stage or in the fall when the 

leaves start to turn yellow. Signs are posted at treatment areas to inform the public of the application of 

herbicides. Similarly, most fungi on the Northwest District emerge after the rains begin later in the fall and are 

done fruiting by early winter. Invasive plant treatments are not conducted when mushrooms (the fruiting body of 

the fungi) are present, and as described in Issue 5, fungi are generally not expected to occur where invasive plants 

occur.

Standard Operating Procedures, PEIS Mitigation Measures, and Oregon FEIS Mitigation Measures designed to 

reduce potential unintended effects to human health are listed in Appendix D. Specific Standard Operating 

Procedures and Mitigation Measures pertinent to this analysis include:

• Prepare an operational and spill contingency plan in advance of treatment.

• Observe restricted entry intervals specified by the herbicide product label.

• Provide public notification in newspapers or other media where the potential exists for public exposure.

• Consult with Native American Tribes to locate any areas of vegetation that are of significance to the Tribes 

and Native groups and that might be affected by herbicide treatments39.

• Use the typical application rate, where feasible, when applying 2,4-D and triclopyr40 to reduce risk to 

workers and the public.

• Consideration should be given to herbicides other than 2,4-D; use of 2,4-D should be limited to situations 

where other herbicides are ineffective or in situations in which the risks posed by 2,4-D can be mitigated.

• Establish a buffer between treatment areas and human residences based on guidance given in the Human 

Health Risk Assessment, with a minimum buffer of 100 feet for ground applications, unless a written 

waiver is granted.

• Consider the potential for treatments to affect communities from herbicide-contaminated resources 

originating from the BLM, such as subsistence resources or water used downstream for human or 

agricultural uses.

• Conduct mixing and loading operations in an area where an accidental spill would not contaminate an 

aquatic body.

• To protect domestic water sources, no herbicide treatments should occur within 100 feet of a well or 200 

feet of a spring or known diversion used as a domestic water source unless a written waiver is granted by 

the user or owner.

• Proposals to boom spray herbicides within 200 feet of streams that are within 1,000 feet upstream from a 

public water supply intake, or spot apply herbicides within 100 feet of streams that are within 500 feet 

upstream from a public water supply intake, will include coordination with the Oregon Department of 

Environmental Quality and the municipality to whom the intake belongs.

• Use appropriate herbicide-free buffer zones for herbicides not labeled for aquatic use based on Risk 

Assessment guidance, with minimum widths from water of 25 feet for vehicle, and 10 feet for hand spray 

applications.

 39 A Project Design Feature states that Annual Treatment Plans will be presented to the Tribes showing planned treatments. 

Any resultant coordination will identify if treatments should be delayed, where cultural features must be avoided or protected, 

and where posting signs would help Tribe members avoid areas (see Issue 21). 40 An Oregon FEIS Mitigation Measure stating, “do not apply triclopyr by any broadcast method” is not applied in this analysis 

because an updated Risk Assessment for triclopyr found zero risk for all worker and public exposure scenarios at the typical 

rate.
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Herbicide use under all alternatives would be scattered and infrequent (typically once per year at a site) and not 

comparable to industrial uses on neighboring farms or timberlands (USDI 2010a:744). The BLM manages 6.7 

percent of the land within the Northwest Oregon District boundary and the BLM use of herbicides is a small 

fraction (0.01 percent) of the pounds of pesticides used in the water basins containing these District-managed 

lands (ODA 2009). Herbicides would not be sprayed aerially and drift reduction strategies would be applied to spot 

and broadcast treatments.

As detailed in the Protection Measures, the BLM would notify the public prior to herbicide applications. The 

Northwest District sends news releases to local newspapers and signs treatment areas prior to the treatment. An 

Annual Treatment Plan would be prepared prior to the beginning of control treatments each year and the resulting 

Determination of NEPA Adequacy, or additional NEPA analysis if warranted, would be made available to the public 

on ePlanning and shared with the Tribes as part of ongoing consultation (see also Issue 21). In addition, the BLM is 

in the process of making NISIMS, the database that contains spatial information on invasive plant infestations, 

accessible to the public, which will allow the public to access data about invasive plant sites.

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2007 and 2016 PEISs. All Standard Operating Procedures and Mitigation Measures 

analyzed in those documents would be applied to all alternatives. 

Issue 12 (Human Health): What are the hazards to workers treating 

invasive plants?

The BLM received comments raising the concern that workers treating invasive plants could be harmed. This issue 

was not analyzed in detail because effects were previously described in the analysis for the Oregon FEIS and the 

2007 and 2016 PEISs (USDI 2010a:345-358, USDI 2007a:4-174 to 4-196, USDI 2016a:4-87 to 4-103) and there are 

no new circumstances or information at the District level that would change the effects anticipated for this EA.

As described in the Human Health and Safety section of the Oregon FEIS, there are difficulties in establishing 

correlations between work conditions and disease and only certain illnesses have been linked to occupational 

hazards in national and state-level studies (USDI 2010a:343). Manual, mechanical, and chemical treatments can all 

present health hazards to workers. Hazards could include falling objects (e.g. when cutting trees such as the 

invasive tree-of-heaven and hawthorn), tripping or slipping on hazards on the ground, protruding objects such as 

branches and twigs, poisonous plants and insects, and dangerous wildlife. Workers are subject to heat-related 

illness (potentially exacerbated by safety equipment such as chainsaw chaps or face guards) or hypothermia when 

working in extreme weather conditions, and may incur musculoskeletal injuries related to improper body 

mechanics (USDI 2010a:343-345). Table G-3 shows herbicides that have some level of risk (greater than 0) to 

applicators in one or more Risk Assessment-modeled scenario.

Table G-3. Human Health Herbicide Risk Summary, Workers

Herbicides

Risk Category

(worst-case scenario, one or more scenarios)

How Often Herbicide Would be Used

No Action Alternative Alternative 

2

Alternative 

Typical rate Maximum rate Accidental Exposure 3

2,4-D L L1 M <1% (Cascades Field Office) 5%2 5%2

Chlorsulfuron 0 L 0 Not used 3% 3%

Dicamba 0 L 0 1% (Cascades Field Office) 5% 5%

Fluridone 0 0 L-H Not used Not used <1%

Hexazinone 0 L1 0 Not used <1% <1%

Rimsulfuron 0 0 M-H Not used <1% <1%

Triclopyr 0 L1 L <1% (West Eugene Wetlands) 23% 23%

1. Limited by Mitigation Measures to typical rate, where feasible.

2. As part of a tank mix. 2,4-D by itself would be used less than 1 percent of the time. 
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As described in the Oregon FEIS and 2007 and 2016 PEISs, modeled scenarios indicate that:

• For 2,4-D and triclopyr, workers face moderate risk from wearing contaminated gloves for an hour (USDI 

2010a:349-350).

• Chlorsulfuron and dicamba at the maximum rate can cause temporary skin or eye irritation to applicators 

(USDI 2007a:4-184, USDI 2010a:350).

• Fluridone can cause reversible eye irritation (USDI 2007a:4-183, USDI 2010a:348).

• Workers applying hexazinone face low risk from spills on lower legs and wearing contaminated gloves. 

The most likely effects would include skin, eye, and respiratory tract irritation (USDI 2007a:4-184, USDI 

2010a:350).

• Rimsulfuron has risks in accidental scenarios. It may cause reversible eye irritation. Long-term exposure at 

high rates (repeated accidental exposure) can cause health effects targeting multiple organs (USDI 

2016a:4-102).

Further information about these modeled scenarios can be found in each herbicide’s human health Risk 

Assessment (See Appendix F, Herbicide Risk Assessment Summaries).

The potential for an injury (from manual, mechanical, or chemical treatments) is exacerbated if workers are 

fatigued, poorly trained, poorly supervised, or do not follow established safety practices. Appropriate training, 

together with monitoring and intervention to correct unsafe practices, minimizes potential for worker injury and 

illness. BLM complies with Standard Operating Procedures, Mitigation Measures, and Occupational Safety and 

Health Administration (OSHA) standards and industry and manufacturers’ recommendations, which reduces 

potential exposure and injury to workers (USDI 2010a:344-345). Herbicide treatments on BLM-administered lands 

in Oregon are done only by BLM certified or state licensed applicators or persons working under their direct 

supervision (USDI 2010a:85). BLM certifications are renewed every three years by completing a one-week EPAcompliant training course.

No injuries to herbicide applicators from herbicide exposure have been recorded for at least the past 20 years on 

BLM-administered lands in Oregon (Erin McConnell, Oregon BLM State Weed Coordinator, 2018 personal 

communication).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2007 and 2016 PEISs. All Standard Operating Procedures and Mitigation Measures 

analyzed in those documents would be applied to all alternatives.

Issue 13 (Human Health): What are effects to human health of mixing 

two or more herbicides? What are the effects from adjuvants and 

other ingredients mixed with herbicides? What are the effects from 

the degradates when herbicides break down?

The BLM received several comments raising the concern that too many things were unknown about herbicides and 

these unknowns may have the potential to harm human health. Specific concerns included tank mixes, adjuvants, 

inerts, and degradates. 

This issue was not analyzed in detail because the effects were previously described in the analysis for the Oregon 

FEIS and the 2007 and 2016 PEISs (USDI 2010a:345-358, USDI 2007a:4-174 to 4-196, USDI 2016a:4-87 to 4-103) 

and there are no new circumstances or information at the District level that would change the effects anticipated 

for this EA. The effects described in Issue 11 (incidental / public exposure) and Issue 12 (worker exposure) reflect 

the potential effects of using two or more herbicides in combination, adjuvants or other ingredients added to an 
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herbicide product, and degradates. To the degree a toxic substance is known to pose a significant human or 

ecological risk, the BLM has undertaken analysis to assess its impacts through Risk Assessments (USDI 2010a:87). 

The BLM is prohibited by law from disclosing the actual inert ingredients because they are considered proprietary

information. However, the Adjuvants, Impurities, and Other Ingredients section in the Oregon FEIS describes the 

BLM analysis of inerts (USDI 2010a:63). The BLM maintains a list of specific products known to contain only the 

materials (including inerts and other ingredients) analyzed in the Risk Assessments. The list of approved herbicides 

and formulations is updated annually (see Appendix E). This nationally approved herbicide formulations list is 

based on the Risk Assessments, which included evaluations of common tank mixes and current research on 

synergistic effects (with other pollutants found in water, for example). Some formulations (brands) approved for 

use on BLM-administered lands contain more than one herbicide active ingredient. Others can be mixed in the 

field (tank mix). BLM can only use herbicides in combinations if each one is included on the BLM-approved 

herbicide list and the label allows for the combination. All herbicides included in the combination must be 

registered for the type of land being treated (forestland, rangeland, etc.). The Risk Assessments consider risks from 

mixing two herbicides together in a tank mix, assuming the products act in an additive manner. When two or more 

active ingredients are used, the risk ratings and Mitigation Measures for all ingredients apply; they are not 

averaged. The combination may be more hazardous to non-target plants than any of the individual herbicides 

being mixed; for example, a few ounces of 2,4-D are sometimes added to other herbicides to increase 

effectiveness and decrease the likelihood of missing otherwise resistant plants (USDI 2010a:62).

Prediction of potential toxic effects from single or synergistic exposure to herbicides and their adjuvants, inerts, 

and degradates, natural and synthesized, necessarily involves incomplete and unavailable information regarding 

the complexity and unpredictability of potential multiple exposures. To address these uncertainties, the Risk 

Assessments use the most conservative observed response and then apply uncertainty factors at each step. The 

combination (product) of these uncertainty factors can be in the tens of thousands in cases where test results 

were sparse or uncertain; the factors applied at each step depend on the level of confidence at that step that the 

results will apply to the full range of potentially affected individuals (USDI 2010a:87). 

Issue 14 (Human Health): What are effects to human health of using 

glyphosate, which a California court recently found to be cancercausing, the International Agency for Research on Cancer (IARC) has 

declared a cancer hazard, and has been found in breakfast cereal?

The BLM received a comment expressing concern about the potential of glyphosate to cause cancer. This issue was 

not analyzed in detail because glyphosate was analyzed in the 2010 Oregon FEIS to which this EA tiers (USDI 

2010a:350), and even considering recent research, effects are not likely to change at the District level.

Endocrine disrupting chemicals, predominately found in man-made materials, are suspected of causing endocrinerelated cancers (breast, endometrial, ovarian, prostate, testicular and thyroid) (Bergman et al. 2012). The Oregon 

FEIS discussed the potential for glyphosate to act as an endocrine disruptor as analyzed in the Risk Assessments41, 

stating, “Three specific tests on the potential effects of glyphosate on the endocrine system have been conducted 

and all of these tests reported no effects. The conclusion that glyphosate is not an endocrine disruptor is 

reinforced by epidemiological studies that have examined relationships between occupational farm exposures to 

glyphosate formulations and risk of spontaneous miscarriage, fecundity, sperm quality, and serum reproductive 

hormone concentrations... the approach taken in the Risk Assessment is highly conservative and no recent 

information has been encountered suggesting that this Risk Assessment is not adequately protective of any 

reproductive effects that might be associated with glyphosate exposure” (USDI 2010a:350).

 

41 The Oregon FEIS discusses results from a 2002 Risk Assessment. The 2011 Risk Assessment (SERA 2011a), also done by SERA, 

includes no new information that would change the analysis. 
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In March 2015, the IARC, the specialized cancer agency of the World Health Organization (WHO), added glyphosate 

to Group 2A, probably carcinogenic to humans. In May 2016, the Food and Agriculture Committee of the WHO 

held their regular Joint Meeting on Pesticide Residues (JMPR), where they found that glyphosate was “unlikely to 

pose carcinogenic risk from exposure through diet.” The WHO also stated that the conclusions arrived at by the 

JMPR and the IARC were “different, yet complementary” noting “the IARC reviews published studies to identify 

potential cancer hazards, it does not estimate the level of risk to the population associated with the hazard.” The 

IARC defines a cancer hazard as an agent that is capable of causing cancer under some circumstances, while a 

cancer risk is an estimate of the carcinogenic effects expected from exposure to that substance. The distinction 

between ‘hazard’ and ‘risk’ is important. The IARC identifies cancer hazards even when risks are very low at current 

exposure levels. Their list of carcinogens describes the level of evidence that something can cause cancer, not how 

likely it is that something will cause cancer in any particular person. Other agents listed in Group 2A include 

drinking hot beverages (over 149° F), eating red meat, and indoor emissions of burning wood (IARC 2015, JMPR 

2016). Based on evidence presented showing IARC’s classification of glyphosate and their evidence submitted in 

support of that classification, in August 2018, a California Superior Court jury ruled that glyphosate had caused the 

cancer of a groundskeeper (Levin and Greenfield 2018).

In June 2016, Reuters reported that court documents from an ongoing legal case against Monsanto (the maker of 

RoundUp herbicide products) show the scientist leading the IARC’s review of glyphosate knew of data showing no 

link between glyphosate and cancer. The agency did not take the information into account because it had yet to be 

published in a scientific journal. In a deposition given in connection with the case, Aaron Blair, a U.S. National 

Cancer Institute epidemiologist, said the data would have altered IARC’s analysis and made it less likely that 

glyphosate would meet the agency’s criteria for being classed as “probably carcinogenic” (Kelland 2017).

In July 2017, California’s Office of Environmental Health Hazard Assessment added glyphosate to their list of 

chemicals known to cause cancer and made plans to require cancer warnings on products. Monsanto challenged 

the product-labeling as “unwarranted on the basis of science and the law” (Plum 2017) and in February 2018, a 

Federal judge in U.S. District Court ruled that “Given the heavy weight of evidence in the record that glyphosate is 

not in fact known to cause cancer, the required warning is factually inaccurate and controversial” (National 

Association of Wheat Growers et al. v. Lauren Zeise, director of OEHHA, et al., U.S. District Court, Eastern District of 

California, No. 17-cv-02401).

Also in July 2017, the European Food Safety Administration and European Chemicals Agency conducted detailed 

evaluations and found insufficient evidence that glyphosate causes cancer. These evaluations were done in 

response to a request from the European Commission regarding their evaluation of the carcinogenicity of 

glyphosate (EFSA 2017). Similar conclusions were found in a recent review and meta-analysis of available research 

examining glyphosate exposure and the risk of lymphohematopoietic cancers (which includes non-Hodgkin 

lymphoma and leukemia) found a “positive and marginally statistically significant association with the use of 

glyphosate,” but “the overall body of literature is methodologically limited and findings are not strong or 

consistent” and that bias and confounding (the presence of another variable that may influence the results) were 

possible. As a result, the report said a causal relationship between glyphosate and lymphohematopoietic cancers 

could not be established (Chang and Delzell 2016).

In August 2018, a report published by the Environmental Working Group found that trace amounts of glyphosate 

were in all but 2 of the 45 products it had tested that were made with conventionally grown oats (Temkin 2018). In 

response, Monsanto issued a statement, saying:

It is not uncommon to find trace amounts of pesticides in food since some food is grown using pesticides, 

which protect crops from insects, disease, and weeds. Importantly, these levels are not even remotely close 

to any level of concern. Regulatory authorities have strict rules when it comes to pesticide residues. The 

Environmental Protection Agency (EPA), for example, sets daily exposure limits at least 100 times 

below levels shown to have no negative effect in safety studies.
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Even at the highest level reported by the EWG (1,300 ppb), an adult would have to eat 118 pounds of the 

food item every day for the rest of their life to reach the EPA’s limit. (Monsanto 2018)

The Oregon FEIS describes that it is difficult to quantify the likelihood of some agent causing cancer due to the 

long-time interval between exposure and diagnosis, personal behavior patterns, job changes, and exposure to 

other carcinogens (USDI 2010a:344). 

Issue 15 (Human Health): What are the effects to human health from 

invasive plants (allergies, rashes, etc.)?

The BLM received a comment expressing concern about the spread of invasive plants having human health effects, 

such as increased incidences of allergies and rashes from coming into contact with invasive plants. This issue was 

not analyzed in detail because the issue does not relate to how the alternatives respond to the purpose and need, 

nor would the alternatives have a potential for significant effects related to this issue. Invasive plants can cause 

harm to human health ranging from scrapes from thorns (e.g., blackberry), rashes and burns from chemical 

compounds produced by a plant (e.g., giant hogweed), or allergic reactions to pollen. One of the factors 

considered by the State in weed risk assessments during the listing process for noxious weeds is how poisonous, 

injurious, or otherwise harmful to humans and/or animals the species is (ODA 2017). While it is one of the listing 

criteria, many noxious weeds do not have an adverse impact on human health; the species meets other criteria 

sufficient for listing. Some species such as tansy ragwort and Scotch broom produce pollen that can cause allergic 

reactions, but this characteristic is not unique to invasive plants and the effects from that one species cannot be 

distinguished from native species that are also concurrently producing pollen. Similarly, native plants such as 

poison oak, poison ivy, and stinging nettle that could repopulate an area formerly occupied by invasive plants can 

cause skin irritation. Though invasive plants are controlled to varying degrees in the alternatives, the effects to 

human health associated with effects such as allergies and burns across the District cannot be distinguished. 

Issue 16 (Soil): How do herbicides detrimentally affect soils?

The BLM received comments expressing concern about herbicides moving through and persisting in the soil and 

harming soil microbiota as well as non-target vegetation that may grow in the soil. This issue was not analyzed in 

detail because effects were previously described in the analysis for the Oregon FEIS and the 2007 and 2016 PEISs 

(USDI 2010a:178-187, USDI 2007a:a4-16, USDI 2016a:4-10 to 4-13) and additional analysis at the District level 

would not change the conclusions from the Oregon FEIS and the 2007 and 2016 PEISs. Proposed herbicide use 

would not cause negative effects to soil due to the limited scale (an average of 450 acres per year under the No 

Action Alternatives and 750 acres under Alternatives 2 and 3) and methods of herbicide application (almost 

entirely spot treatments under the No Action and 95 percent spot treatments under the action alternatives). In 

addition, if there were site conditions in which adverse effects could occur (e.g., broadcast treatments), the BLM 

would apply Protection Measures that minimize the potential for effects. 

The ability of soils to hold and break down herbicides is affected by biological processes (organisms and plant 

uptake), physical parameters (adsorption, volatilization, hydrolysis, and leaching), and other parameters (climate, 

slope, and vegetative cover) (USDI 2010a:178-187, USDI 2007a:4-16, USDI 2016a:4-10 to 4-13). Soils on the District 

range in texture classes from sandy loams to clays (weighted average of 23 percent clay), and are high in organic 

matter (weighted average of 14 percent), meaning soils within the District have high adsorption capacity and

herbicides applied to soils may attach to and potentially move with them (USDI 2010a:179-181, USDI 2007a:4-14, 

USDI 2016a:4-11). In the cases where herbicides move down through the soil, the main concern is groundwater 

contamination (discussed further in Issue 17).

The Oregon FEIS describes that in the event herbicides do make contact with the soil, herbicides affect few soil 

organisms directly (USDI 2010a:178). While there are varying amounts of information available for each herbicide, 
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chlorsulfuron, picloram, and metsulfuron methyl would reduce the presence of soil biota for a period of up to 

three weeks; the remaining herbicides have no or slight adverse effects (USDI 2010a:182-185, USDI 2007a:4-16, 

USDI 2016a:4-11 to 4-13). When effects were noted (diflufenzopyr, imazapic, or imazapyr), it was at application 

rates many times higher than those used by the BLM. Hexazinone and imazapyr have little data about their effects 

to soil life, and available studies had application rates many times higher than proposed for BLM-administered land

(USDI 2010a:178). 

Fluazifop-P-butyl and sethoxydim, proposed for use in limited areas for research and demonstration, were not 

analyzed in the EISs to which this document tiers. These herbicides would not be expected to have short (within 

the growing season of the treatment) or long term (after the growing season of the treatment) soil effects due to 

their chemical characteristics and because each would only ever be used on 15 acres or less per field office. The 

Risk Assessment for fluazifop-P-butyl discusses adverse effects on terrestrial arthropods at the treated site, and 

explains that functional recovery (i.e., repopulation) within one year would be expected and no effects would be 

expected at a distance of 100 feet from the treated site, indicating highly localized, temporary effects (SERA 2014). 

Sethoxydim’s Risk Assessment indicates it is relatively non-toxic to terrestrial animals including some invertebrates 

at higher application rates than are proposed in this EA (SERA 2001).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2007 and 2016 PEISs. All Standard Operating Procedures and Mitigation Measures 

analyzed in those documents would be applied to all alternatives (see Appendix D). Given the quantity used and 

the distribution across the District, localized effects to soil function from all other herbicides would be negligible 

(not be detectable or measurable).

Issue 17 (Water): How do herbicides treating terrestrial weeds affect 

water quality, including ground and surface water used for domestic 

and municipal supply?

The BLM received comments expressing concern that herbicides may inadvertently end up in surface and 

groundwater that could be used for drinking, irrigation, or other human uses. This issue was not analyzed in detail 

because effects were previously described in the analysis for the Oregon FEIS and the 2016 PEIS (USDI 2010a:204-

206, USDI 2016a:4-19) and there are no new circumstances or information at the site-specific level that would 

change the effects anticipated for this EA. The type of actions and the amount of treatments under all alternatives 

are wholly within the actions analyzed in the 2010 Oregon FEIS and 2016 PEIS. 

The routes for herbicides to contaminate water include accidental spills, drift into streams from spraying, runoff 

(e.g., from a rainstorm soon after application), and leaching through soil into groundwater. The potential for 

groundwater contamination is influenced by depth to groundwater, soil conditions, and rainfall. The proportion of 

herbicide that is on or in the plant, soil, and water after application influences whether an herbicide will runoff or 

drift; application method, weather conditions (application timing), herbicide formulation and application rate, and 

amount and type of vegetation and groundcover influence this proportion (Kerle et al. 2007). The potential for 

impacts from herbicide drift, runoff, or spills would be reduced by Standard Operating Procedures that require 

buffers from water; the Oregon FEIS describes that buffers are effective at reducing the movement of herbicide to 

streams (Berg 2004, Dent and Robben 2000, Rashin and Graber 1993 all cited in USDI 2010a:205). The BLM would 

primarily use spot treatments for herbicide applications because the applicator can target specific plants and 

minimize herbicide contact with the soil or water. Drift reduction agents would be used when necessary. The BLM 

would apply herbicides primarily during the dry season (May through September with applications outside this 

period only if rainfall is not expected) allowing time for microbial, chemical, and photo degradation prior to 

rainfall.
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During preparation of the Annual Treatment Plan, the BLM would identify domestic water sources, areas with 

shallow groundwater, and areas of groundwater-surface water interaction and suggest appropriate treatment 

methods to minimize the risk of herbicide leaching. There are many exempt uses for groundwater that do not 

require a water right (OWRD 2013) so it is possible that unknown wells exist on BLM-administered land. BLM 

notification of adjoining landowners prior to herbicide application gives the public an opportunity to disclose the 

location of water systems so the BLM can implement water quality protection measures. In conjunction with the 

interdisciplinary team review of the Annual Treatment Plan, District hydrologists would consult these records to 

make sure that water right holders are aware of proposed herbicide treatments in their area, and to eliminate or 

minimize the risk of water contamination. Wells or springs, when proximate to treatment areas, would be buffered 

from herbicide treatments.

If herbicides do reach domestic-use water sources despite Protection Measures, Risk Assessments for human 

consumption of contaminated water show no risk at typical rates of application for all herbicides and low risk for 

clopyralid, dicamba, triclopyr, and glyphosate applied at the maximum rate (see Issue 11 for additional detail). 

Mitigation Measures limit triclopyr application to the typical rate where feasible, and BLM would apply clopyralid 

at typical to less than maximum application rates, thereby reducing the already low risk associated with these 

herbicides.

Issue 18 (Water): How do herbicide treatments of aquatic invasive 

plants affect water quality?

As described in Issue 17, the BLM received comments that requested analysis for the potential for herbicides to 

affect water quality. This issue examines the use of herbicide treatment of aquatic invasive plants as proposed 

under Alternative 3. This issue was not analyzed in detail because effects were previously described in the analysis 

for the 2007 PEIS and the Oregon FEIS (USDI 2010a:205) and there are no new circumstances or information at the 

District level that would change the effects anticipated for this EA. All of the herbicides proposed for treatment of 

aquatic invasive plants in this EA were analyzed in the PEIS and the Oregon FEIS. The Oregon FEIS concluded that 

treating aquatic invasive plants would result in improved water quality (USDI 2010a:205).

There are 8,225 miles of water quality limited streams and lakes within the analysis area, some of which are 

impaired due to the presence of aquatic invasive plants. Under Alternative 3, fluridone and aquatic formulations of 

2,4-D, glyphosate, imazapyr, and triclopyr would be available to treat submerged and floating aquatic invasive 

plants and emergent aquatic invasive plant infestations. Although these herbicides could be applied across the 

Northwest Oregon District, at present, the only aquatic infestations known to occur on the District include areas

that total less than one acre: three sites at the Hult Pond (parrot feather) and one site along Kelly Creek (yellow 

flag iris). These aquatic treatments are a high priority for the Northwest Oregon District to prevent them from 

spreading further.

As described in Chapter 2, treatments of aquatic invasive plants with fluridone would only occur in closed aquatic 

habitats that do not flow into streams during the treatment window. These are typically ponds and lakes, or 

sloughs and pools of standing water on floodplains connected to rivers only during high water events. Aquatic 

invasive plants in streams and rivers would only be treated with herbicides when water levels are at their lowest 

and the invasive plants that were previously submerged or floating are no longer in flowing water: 2,4-D, 

glyphosate, imazapyr, and triclopyr would be applied to the plants above the water line (foliage sticking out of the 

water or foliage on banks that had previously been submerged).

As described in the 2007 PEIS, glyphosate dissipates rapidly from surface water through adsorption to organic 

substances and inorganic clays and by biodegradation. It does not photodegrade, and in water has an estimated 

half-life of 12 days to 10 weeks (USDI 2007a:4-30). The salt formulation of 2,4-D is registered for use in aquatic 

systems. There are conflicting conclusions regarding biodegradation of 2,4-D in aquatic systems. Biodegradation 

can take place in bottom sediments if the appropriate microbial population is present and the pH level is 
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sufficiently high, but it is not likely to occur in the water column (USDI 2007a:4-30). Imazapyr is water soluble and 

potentially mobile (SERA 2011b). Imazapyr is rapidly degraded by sunlight in aquatic solutions, with a half-life of 

approximately 2 days that decreases with increasing pH (USDI 2007e:4-30). Triclopyr TEA (the aquatic formulation) 

is soluble in water and photodegrades in several hours with adequate sunlight. Field studies have shown that it 

dissipates from water, with a half-life ranging from 0.5 to 10 days and a sediment dissipation half-life ranging from 

3 to 13 days. The rate of degradation in water is generally dependent on water temperature, pH, and sediment 

content (USDI 2007a:4-31).

Water quality is not degraded when fluridone is used at a concentration of less than 20 ppb, and there are no label 

restrictions against swimming, fishing, or drinking treated water (Washington Department of Ecology 2002). 

Whole-lake treatments using fluridone are possible because the herbicide does not cause a rapid plant kill, which 

would otherwise result in oxygen-depleted water and reduced water quality (USDI 2010a:197). A Project Design 

Feature adopted for this EA would delay treating side channels and connected backwaters with any herbicide until 

periods of low flow or when the mainstem river is disconnected (see Chapter 3, Issue 2). 

Issue 19 (Air): How would the alternatives affect air quality?

The BLM received a comment that requested analysis of the potential for invasive plant treatments to generate 

dust or vehicle emissions. This issue was not analyzed in detail because effects were previously described in the 

analysis for the Oregon FEIS and the 2016 PEIS (USDI 2010a:166-172, USDI 2016a:4-9) and there are no new 

circumstances or information at the District level that would change the effects anticipated for this EA. Those 

documents concluded that prescribed fire is the only treatment method with the potential to affect air quality and 

that herbicide applications do not have an effect.

In general, the air quality in Northwest Oregon is good but with persistent problem areas where strong inversions 

tend to trap either carbon monoxide (CO) or particulate matter at certain times of the year concentrated around 

inland valleys. Poor air quality can develop when a major polluting activity or event combines with temperature 

inversions and strong high-pressure systems that create stagnant air. The Northwest Oregon district includes the 

following National Ambient Air Quality Standards non-attainment or maintenance areas: Portland Metro, Salem, 

Eugene-Springfield, and Oakridge. The District includes the following Smoke Sensitive Receptor Areas: the entire 

floor of the Willamette Valley, Oakridge, Astoria, Tillamook, Lincoln City, and Newport (ODF 2016). Air quality and 

smoke clearances on the District are regulated by Oregon Department of Forestry and Lane Regional Air Protection 

Agency.

The Oregon FEIS showed that emissions from invasive plant treatments on all Oregon BLM-administered lands 

would be less than 0.1 percent of statewide emissions of CO, nitrogen oxides (NOx), sulfur dioxide (SO2), and 

Volatile Organic Compound (VOCs) and 0.2 percent of particulate matter (PM) (USDI 2010a:167). Emissions from 

prescribed fire were the primary air quality concern in an integrated invasive plant management program (USDI 

2010a:165, USDI 2007d); the herbicides analyzed in the 2010 Oregon FEIS contribute less than 1 percent of the 

aforementioned SO2, less than 0.1 percent of the CO, and less than 0.2 percent of the NOx, VOCs, and PM (USDI 

2010a:167). The Oregon FEIS did not discuss the effects of aminopyralid, fluroxypyr, or rimsulfuron; the 2016 PEIS 

states that annual emissions nationwide from a program that included the three additional herbicides would be 

similar to the program without those three herbicides (USDI 2016a:4-9).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in 

those documents would be applied to all alternatives, including evaluating weather conditions prior to 

implementing treatments and coordinating with officials to obtain all applicable smoke management permits and 

ensure that burn plans comply with regulations and would minimize adverse effects. On the Northwest Oregon 

District, effects from herbicide applications on local and regional air quality would be undetectable. The amount of 
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herbicides used would be within the amount analyzed in the Oregon FEIS. All alternatives would have no effect on 

air quality.

Issue 20 (Air): How would the alternatives affect climate change, 

including greenhouse gas emissions and carbon storage?

The BLM received a comment that requested analysis of the potential for invasive plant treatments to affect 

greenhouse gases and climate change. This issue was not analyzed in detail because effects were previously 

described in the analysis for the Oregon FEIS and the 2007 and 2016 PEISs (USDI 2010a:166-172, USDI 2007a:4-9 

and 4-10, USDI 2016a:4-9) and there are no new circumstances or information at the District level that would 

change the effects anticipated for this EA. Along with the general lack of detailed information concerning existing 

carbon storage and storage capacity, climate responses to changes in greenhouse gas emissions and carbon 

storage rates are non-linear, making any assessment of potential effects of the alternatives on climate largely 

speculative (USDI 2010a:174).

The Oregon FEIS discusses that emissions from biocontrols, targeted livestock grazing, and seeding or planting are 

considered to have a negligible effect on climate change (USDI 2010a:166). Acres of mechanical treatments are 

expected to decline under Alternative 2 and Alternative 3 from 1,275 acres (No Action Alternative) to 1,013 acres 

(Alternative 2 and Alternative 3) over the life of the plan and associated fugitive dust and exhaust emissions would 

decline as well. However, the BLM does not have adequate data to quantify potential greenhouse gas emissions 

from that change.

The 2016 PEIS states that none of the herbicides analyzed in the 2007 or 2016 PEISs were expected to have an 

adverse effect on greenhouse gas emissions given the relatively low amount of greenhouse gas emissions 

associated with herbicide treatments, and the role of invasive plant control in reducing the extent, frequency, and 

severity of wildfires (a contributor to greenhouse gas emissions) (USDI 2016a:4-9). Effects did not differ because of 

the herbicide used; rather, levels of effects were related to the acres treated and associated trip distance, vehicle 

exhaust, and fugitive dust. A quantitative analysis of carbon sequestration was not completed, as there is no 

appropriate protocol for evaluating impacts (USDI 2016a:4-6).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2007 and 2016 PEISs. All Standard Operating Procedures and Mitigation Measures 

analyzed in those documents would be applied to all alternatives. Alternatives that control or reduce invasive 

plants maintain or enhance net carbon storage capacity. Alternatives that allow invasive plants to spread reduce 

net carbon storage capacity (USDI 2010a:172). Since the annual acres treated would remain the same under all 

alternatives (an average of 3,000 gross acres), there would be no difference in carbon storage between the 

alternatives. Alternative 2 and Alternative 3 would reduce invasive plant spread (see Issue 1 in Chapter 3), so there 

would be a net carbon storage capacity increase associated with those alternatives (USDI 2010a:173-174).

Issue 21 (Traditional and Cultural Uses): How would the treatment of 

invasive plants affect plant resources used by Native Americans given 

that these plants (or their locations) may not be known by the BLM?

This issue was not analyzed in detail because effects were previously described in the analysis for the Oregon FEIS 

and the 2016 PEIS (USDI 2010a:286-289, USDI 2016a:4-71 and 4-72) and there are no new circumstances or 

information at the District level that would change the effects anticipated for this EA. The risk of adverse effects is 

further minimized as a result of a Project Design Feature included with the action alternatives, which requires 

additional consultation or coordination, if requested by the Tribe, to avoid conflict with tribal resource use. 
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Four federally recognized tribes have historic ties to the lands managed by the Northwest Oregon District of the 

BLM. These include ancestral or aboriginal lands and ceded lands, as well as usual and accustomed places. 

Historically, Native Americans managed, gathered, and utilized a wide array of plants from these lands. Tribal 

members today continue to gather culturally important plants from public lands for a multitude of purposes, and 

continue to take an active role in the management of their ancestral lands. Many areas within the District are 

locales for culturally significant plants. Tribal members gather plants for edible, medicinal, ceremonial, and 

utilitarian purposes and often keep the location of these sites private; therefore, the BLM does not have 

knowledge of them. These areas are often considered sacred sites and places of traditional and cultural 

importance. The BLM manages the sites of which it is aware, in consultation with Tribes. In preparation of the 

Resource Management Plans of Western Oregon, to which this EA tiers, Tribes identified an interest in managing 

for culturally important plants within riparian habitat areas along the coast, though Tribal use is not limited to 

these areas (USDI 2016e:801). A list of common cultural plants of importance to Tribes in western Oregon was 

compiled for the Resource Management Plan and is incorporated by reference in this EA (USDI 2016e:1644). 

Culturally important plants may occur near invasive plant treatment areas. These traditionally gathered plants 

might be exposed to incidental contamination from drift when herbicides are used on invasive plants. The Oregon 

FEIS concluded that having the broader mix of herbicides would increase the options for appropriately managing 

invasive plants while minimizing the risk to humans, including Native Americans gathering traditional resources 

near the treatment areas (USDI 2010a:289). Issues 11 through 14 address the potential risk to human health 

associated with exposure to herbicide treatments. While there is a measurable risk under Risk Assessment 

modeled scenarios involving some of the herbicides analyzed in this EA (see Issue 11 and Table G-2, Summary of 

Effects of Herbicides on Human Health), the actual effects would be minimal because of how the herbicides are 

applied under all alternatives (spot sprayed in 95 percent of herbicide treatments, at lower rates than analyzed in 

the Risk Assessments) and because of Protection Measures described in Appendix D that are applicable to all 

alternatives. These include posting treated areas with signs and consulting with Tribes to identify areas of 

vegetation of Tribal significance. The 2016 PEIS stated that aminopyralid, fluroxypyr, and rimsulfuron have low to 

no risk, even under worst case accidental exposures, and would result in less use of other herbicides, such as 2,4-D, 

that have more human health risks (USDI 2016a:4-74; see Issues 11 through 14 for more information). It is 

expected that the treatment of invasive plants would improve the habitat for traditionally gathered plants, as 

treatments would reduce habitat competition.

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in 

those documents would be applied to all alternatives. The following Project Design Feature, included in the 

analysis of Alternatives 2 and 3, would minimize the potential for invasive plant treatments affecting plants that 

may be important to Native Americans:

• At least one month prior to beginning treatments for the season, Annual Treatment Plans would be 

presented to potentially affected Tribes showing planned treatments and treatment areas. If these Tribes 

request coordination or consultation regarding proposed treatments, the BLM would seek to avoid 

conflict with tribal resource use by modifying the timing of treatments or posting signs to allow Tribal 

members to avoid treated areas. These proposed modifications would be determined in coordination 

with the Tribe and are not limited to those stated above. Additionally, modification to Annual Treatment 

Plans may be requested in order to avoid adverse affects to cultural features. Ultimately, a line officer will 

make an informed decision regarding the level of modification appropriate through tribal coordination or 

consultation. 

Coordination may occur using a variety of methods. For example, the Tribes could share this information in Tribal 

newsletters and social media or work with the BLM to conduct seasonally appropriate site-specific field trips.

Additional information about the effects of treatment methods on non-target vegetation can be found in Issue 4

and effects from the consumption of treated vegetation can be found in Issue 11. Issue 11 also discusses how the 

public and Tribes will be notified of proposed herbicide treatments. 
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Issue 22 (Environmental Justice): How would the use of herbicides 

affect minorities and low-income populations?

The BLM received a comment that requested analysis of the effects of the alternatives on populations that could 

be considered environmental justice populations. This issue was not analyzed in detail because this issue was 

addressed in the 2010 Oregon FEIS (USDI 2010a:251-253). There are no new circumstances or information at the 

District level that would change the effects anticipated for this EA.

This EA incorporates by reference information presented in the Proposed Resource Management Plan / Final 

Environmental Impact Statement for Resource Management Plans for Western Oregon for the identification of the 

communities meeting environmental justice criteria within the Northwest Oregon District (USDI 2016e:725-733). 

Low-income and poverty populations are scattered throughout District boundaries (USDI 2016e:Map 3-9). Minority 

populations tend to be clustered in the Willamette Valley around the Portland and Salem metropolitan areas with 

a few populations and tribal lands located around Lincoln, Benton, Polk and Yamhill Counties (see USDI 2016e:Map 

3-8).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in the 

2010 Oregon FEIS and 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in those 

documents would be applied to all alternatives. The FEIS analysis found a potential for contract and other crews to 

include a small disproportionate number of minority, poor (defined as below Federal poverty standards), or both 

and that “American Indian and visitors from other racial, ethnic, or low-income backgrounds participating in 

subsistence or cultural uses could be adversely affected by herbicide exposure, or by inadvertent effects to nontarget culturally important plants, or to wildlife species of value to these groups” (USDI 2010a:333). However, that 

analysis noted such effects would be partially mitigated by protection measures that minimize exposure of nontarget food and water sources, and Standard Operating Procedures requiring consultation with Tribes to locate any 

areas of vegetation that are significant to the tribes and that might be affected by herbicide treatments. Issues 11 

and 12 address the potential for public and worker exposure to herbicide and non-herbicide treatments and finds

that while there is the potential for risk to workers or the public under some scenarios, that risk is low under all 

alternatives. The FEIS analysis also notes that the natural resources used for cultural or subsistence purposes 

would be adversely affected by the spread of invasive plants; this adverse effect would be greater under the No 

Action Alternative (USDI 2010a:333).

Issue 23 (Socioeconomics): What are the impacts to local timber 

production, forest products, agriculture, and recreation economies 

from the management of invasive plants in the Northwest Oregon 

District?

The BLM received comments concerning the effects of the invasive plant program on surrounding resource-based 

land uses such as forest-dependent industries, agriculture, and recreation. This issue was not analyzed in detail 

because the potential for significance of these effects was previously analyzed in the selected alternative for the 

2010 Oregon FEIS and 2016 PEIS. That analysis concluded that the management of invasive plants by the BLM has 

an indirect beneficial effect on those parts of the local economy that rely on natural resource values (USDI 

2010a:309) and that the level of risk to commercial activities on public lands and adjacent private property would 

not be affected by the alternatives (USDI 2016a:4-86). There is no new information at the District level that would 

change the effects anticipated beyond those considered in the 2010 Oregon FEIS and 2016 PEIS.
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The Northwest Oregon District manages approximately 714,395 acres of public lands in 14 counties (see Map 1-1) 

and the administrative boundaries include the largest metropolitan areas in Oregon (Portland, Eugene, and Salem). 

Communities in the growing urban centers of the Willamette Valley value public land for recreational, commodity, 

and non-commodity uses (USDI 2010a:319). Outside of these urban areas, agricultural traditions are valued and

are a part of the culture of many Oregonians. The forest products industry is important throughout the western 

Oregon regional economy, albeit not as large a percentage as other Districts in Oregon (such as Roseburg, Coos 

Bay, and Klamath Falls Resource Area) due to the overall size and diversity of the contributing components of the 

economy (USDI 2016e:667). Similarly, the Northwest Oregon District has the highest visitor-day counts and highest 

recreation values of any district in western Oregon (USDI 2016e:612).

The 2010 Oregon FEIS and 2016 PEIS describe how invasive plant management activities on BLM-administered 

lands would affect local economies (USDI 2010a:318, USDI 2016a:4-82). Invasive plants result in direct economic 

losses on agriculture and timber lands where invasive plants compete with desired crop species, which leads to 

lost harvest and land value (ODA 2014). Invasive plants can also limit recreation access and degrade the resource 

that the recreation relies on (e.g., water, wildlife, etc.) (USDI 2010a:304-305). Management of invasive plants 

contributes to costs that take away from overall economic benefits through increased unit costs and decreased 

profit margins (USDI 2010a:343). However, despite these costs, management of invasive plants reduces economic 

impacts overall. The 2010 Oregon FEIS states that treatments under the action alternatives would result in 

improvements in the conditions of BLM resources and would lead to increases in commodity, non-commodity, and 

non-market values (e.g. improved recreation opportunities or habitat improvements)(USDI 2010a:343).

A 2014 report described the direct negative economic impacts associated with resources losses from noxious 

weeds in the state of Oregon, the additional costs associated when noxious weeds expand to new areas, and the 

positive return on investment associated with control (ODA 201442). That study estimated annual income losses of 

$83.5 million to the State's economy from 25 noxious weed species. If left uncontrolled, the study identified 

annual losses reaching $1.8 billion in personal income and 40,800 jobs (ODA 2014). Two of the 25 selected noxious 

weeds, Himalayan blackberry and Scotch broom (the latter being a particular problem in forests) are abundant 

(across western Oregon and on the Northwest Oregon District) and contribute $79.6 million to the current overall 

economic impact. A similar analysis found that in Washington State, invasive species created losses of $239.5 

million in agriculture, $120 million in the livestock industry, $125 million in the timber industry, and $20 million in 

recreation. Scotch broom was found to be one of the most costly plant species (Community Attributes Inc. 2017). 

While neither of these studies was specific to the Northwest Oregon District, both demonstrate that invasive 

species have an economic effect on resources, lands, and opportunities.

The type of actions and the amount of treatments under all alternatives are wholly within the actions of the selected 

alternative analyzed in the 2010 Oregon FEIS and 2016 PEIS. All Standard Operating Procedures and Mitigation 

Measures analyzed in those documents would be applied to all alternatives. For example, as described in Issue 25, 

treatments would be scheduled to avoid peak recreational use times. Additionally, treatments with herbicides in 

developed recreation sites would be spot treatments to individual plants (not broadcast treatments), which would 

limit potential exposure to visitors. Existing Department of the Interior policy directs the BLM to accomplish pest 

management through cost-effective means that pose the least risk to humans, natural and cultural resources, and 

the environment (USDI 2007e). 

Adjacent landowners, county, State, and other Federal lands benefit from the BLM having a broader range of 

herbicides available for consideration. Having the appropriate range of herbicides available to manage the invasive 

plants in the Northwest Oregon District would improve the BLM’s ability to prevent invasive plant spread from 

BLM-administered lands to private, county, State, and other Federal lands. The effectiveness of herbicides on 

invasive plant management across boundaries is analyzed in detail under Issue 1 (see Chapter 3).

 42 ODA (2014) is an updated version of the Radtke and Davis (2000) report that was referenced in the Oregon FEIS.
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Issue 24 (Socioeconomics): What is the potential for herbicide 

contamination of yards, gardens, organic farms, vineyards, and bee 

hives on private lands?

The BLM received comments raising a concern about herbicides drifting onto private lands that may support farms, 

gardens, and other agricultural uses. This issue was not analyzed in detail because effects were previously 

described in the analysis of the selected alternative for the 2010 Oregon FEIS and the 2016 PEIS (USDI 2010a:145, 

USDI 2016a:4-81). That analysis concluded that private lands are protected from BLM-applied herbicides by 

Standard Operating Procedures to prevent off-site movement from the treatment site. There is no new 

information at the District level that would change the effects anticipated for this EA beyond those considered in 

the 2010 Oregon FEIS and 2016 PEIS. The type of actions and the amount of treatments under all alternatives are 

wholly within the actions analyzed for the selected alternative in the 2010 Oregon FEIS and 2016 PEIS. The same 

Standard Operating Procedures and Mitigation Measures analyzed in those documents would be applied to all 

alternatives in this EA.

The 2010 Oregon FEIS stated that residential lands and agricultural lands, where crops (including orchards, 

vineyards, and pastures) are grown are protected from drift of BLM applied herbicides by Standard Operating 

Procedures that include no-spray buffers, drift reduction measures, and other practices that minimize or eliminate 

herbicide drift or off-site movement (USDI 2010a:145). Those same Standard Operating Procedures were also 

included in the 2007 and 2016 PEISs that concluded those procedures would prevent effects on private land. The 

Standard Operating Procedures are also common to all alternatives in this EA and preclude ground spraying within 

100 feet of a residence without written permission from the owner or occupant.

The herbicides that the BLM uses have very low vapor pressures and would not travel further than 9 to 27 meters 

downwind of the application site (Vencill et al. 2002). Further, herbicide application methods used on the District 

are not those that are prone to drift. Under the No Action Alternative, 85 percent of treatments would be with 

non-herbicide methods and almost all herbicide treatments would be spot treatments. Under the action 

alternatives, herbicide use would increase to 75 percent of treatments, but spot treatments would still be the 

method of application 95 percent of the time. Aerial applications have not and would not be used. Drift and 

methods for drift control are discussed further in Appendix F, Herbicide Risk Assessment Summaries. 

Bees would not be directly affected by the BLM’s herbicide use. The effects from herbicides to pollinators would be 

related to habitat (vegetation) loss, but treatments proposed under the alternatives would be small: 85 percent of 

known sites are less than 1 acre (see Table A-1, Summary of Invasive Plants Documented in NISIMS by Infestation 

Size). The alternatives would conform with recommendations from the 2014 Presidential Pollinator Task Force; 

Standard Operating Procedures and Mitigation Measures for pollinators outlined in Appendix D conform to the 

National Strategy to Promote the Health of Honey Bees and Other Pollinators. The effects of herbicides on 

pollinators are addressed in Issue 8 and the effects of herbicides on vegetation are described in Issue 4.

Issue 25 (Recreation): How will invasive plant management affect the 

management and use of recreation sites?

The BLM received comments concerning the effects of the invasive plant program on access to public recreation 

opportunities. This issue is not analyzed in detail because effects were previously described in the analysis for the 

Oregon FEIS and the 2016 PEIS (USDI 2010a:309, USDI 2016a:4-81) and there are no new circumstances or 

information at the site-specific level that would change the effects anticipated for this EA.

As described in the Oregon FEIS, manual methods would continue to be the primary form of treatment of invasive 

plants in developed recreation sites (USDI 2010a:309). When herbicides are used, recreation sites may be 
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temporarily closed, potentially inconveniencing public land visitors, but reducing herbicide exposure. Access to a 

site treated with an herbicide may be restricted for a few hours or days, depending on the reentry requirements of 

the herbicide label. When recreation sites are closed, BLM posts signs noting the exclusion area, the duration of 

the exclusion, and nearby alternative recreation areas that would provide substantially similar recreation 

opportunities. The Oregon FEIS also notes that the additional herbicides would “often allow the use of an herbicide 

that is more target specific and generally less toxic to humans, and more effective in lower doses, thereby reducing 

the adverse effects of herbicide use on the recreational resource and reducing the chance for accidental exposure 

to recreationists” (USDI 2010a:308-9). The Oregon FEIS did not discuss the effects of aminopyralid, fluroxypyr, or 

rimsulfuron; the effects of these three herbicides were discussed in the 2016 PEIS, which states that impacts to 

recreation nationwide from a program that included these three herbicides would be similar to the program 

without those three herbicides (USDI 2016a:4-81).

The District had 2,590,340 visitors in 2017. The majority of BLM-administered lands on the District are managed to 

accommodate and provide for a multitude of developed, semi-developed, and dispersed recreation uses. Popular 

recreation sites on the District include Fishermen’s Bend Campground, Shotgun Creek Day-Use, Yaquina Head 

Outstanding Natural Area, Carpenter’s Bypass Trails, Upper Nestucca Off Highway Vehicle Trails, Shotgun Creek Off 

Highway Vehicle Trails, Sandy Ridge Trails, Wildwood Day-Use, and Fall Creek Trails. In total, the District has 38 

developed recreation sites and numerous trailheads into trail systems such as the Molalla Shared Use Trail System 

and Table Rock Wilderness. Invasive plant species line recreation access roads and in some locations such as 

Fishermen’s Bend, cover nearly the whole 177-acre site. As stated in a Standard Operating Procedure, most 

treatments would be scheduled to avoid peak recreational use times. Treatments with herbicides in developed 

recreation sites would generally be spot treatments43 to target specific plants, which would limit potential 

exposure to visitors.

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in 

those documents would be applied to all alternatives. The effects of herbicides on human health in situations that 

are applicable to recreators are discussed in Issue 11 earlier in this EA. Recreation is also discussed in Issue 26. 

Issue 26 (Recreation): What are the effects of herbicides on dogs, 

horses, and other pets that accompany recreationists?

The BLM received a comment raising a concern about the effects of herbicides on dogs. In consideration of this 

concern, the BLM also looked at the effects of herbicides on other pets that may accompany recreationists. This 

issue was not analyzed in detail because there is no potential for significant effects to pets and other animals that 

accompany recreationists (e.g., horses, dogs, llamas). As described in Issue 25, existing Protection Measures 

(Appendix D) such as temporary closures would limit the exposure of recreationists to herbicides. When feasible, 

treatments would be scheduled to avoid peak use and most treatments are spot treatments targeting individual 

plants in small areas (85 percent of sites are less than one gross acre) minimizing the likelihood that people and 

animals would be exposed. As required by existing Protection Measures (see Appendix D), treatment areas are 

posted to alert people to avoid areas and further minimize exposure potential.

Risk Assessments (summarized in Appendix F) indicate potential risks to small and large mammals. While there is 

some level of risk to some mammals under certain scenarios, these particular scenarios are unlikely to be 

applicable to pets or other domesticated animals. The Risk Assessments indicate that there is 0 risk to mammals 

under all direct spray scenarios (dermal exposure to herbicides) except for 100 percent absorption scenarios for 

2,4-D, clopyralid, glyphosate, metsulfuron methyl, and triclopyr, where there would be a low risk. There is a 

potential for moderate or high risks to large mammals (e.g. horses) if they were to consume grass treated with 

 

43 While broadcast treatments are allowed 5 percent of the time under the action alternatives when herbicides are used, this 

would happen less than 1 percent of the time in developed recreation areas.
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dicamba or triclopyr, but dicamba and triclopyr would not be used to treat invasive grasses (see Tables C-1 and C19, Treatment Key) and the scenario assumed that the large mammal would feed on contaminated grass for an 

entire day (see Appendix F). Scenarios that involve small or large mammals consuming contaminated insects or 

smaller mammals are all 0 or low risk (see Appendix F). Because of the level of risk to mammals from these 

herbicides, the nature of invasive plant treatments, and Protection Measures applicable to all alternatives, adverse 

effects to pets because of exposure would not occur under any alternative.

Issue 27 (Wilderness / Wilderness Study Areas): How will invasive 

plant management affect Wilderness or Wilderness Study Areas on 

the District?

The BLM received a comment concerning the protection of special management areas by controlling invasive 

plants. To consider this issue, the BLM looked at how the invasive plant program affects Wilderness and 

Wilderness Study Areas. This issue was not analyzed in detail because effects are likely to be minimal, as previously 

described in the analysis for the Oregon FEIS and the 2016 PEIS (USDI 2010a:300-304, USDI 2016a:4-79). There are 

no new circumstances or information at the District level that would change the effects anticipated for this EA.

The Oregon FEIS describes that, for special areas such as Wilderness, treatments could have short-term and usually 

negligible negative effects for the first year following treatment, but that in the long term, effects would be 

beneficial to special area values because of the return of native vegetation (USDI 2010a:301). The short-term 

negative effects of treatments would vary based on which herbicide is applied and how it is applied but when 

herbicides are applied using a backpack sprayer or wicking method, the effect is not easily discernable (USDI 

2010a:294). The Oregon FEIS also states that with a broader array of herbicides, the BLM would have the 

opportunity to substitute more effective and more selective herbicides than those currently being used in special 

areas (USDI 2010a:303). The Oregon FEIS did not discuss the effects of aminopyralid, fluroxypyr, or rimsulfuron. 

The effects of these three herbicides were discussed in the 2016 PEIS, which states that impacts to Wilderness 

nationwide from a program that included these three herbicides would be similar to the program without those 

three herbicides; the strict guidelines for vegetation treatments would prevent actions that would degrade the 

quality, character, and integrity of special management areas (USDI 2016a:4-77 to 4-79).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in 

those documents would be applied to all alternatives. The result of an invasive plant management program with 

more effective herbicides under Alternative 2 and Alternative 3 would allow the District to selectively treat 

invasive plants with fewer retreatments.

Issue 28 (Visual): Would the use of invasive plant treatments affect 

the visual quality of the landscape?

The BLM received a comment expressing concern that the use of herbicides would affect the visual quality of the 

landscape by leaving large dead areas and that many invasive plants are pretty. This issue was not analyzed in 

detail because effects were previously described in the analysis for the Oregon FEIS and the 2016 PEIS (USDI 

2010a:293-295, USDI 2016a:4-77) and there are no new circumstances or information at the District level that 

would change the effects anticipated for this EA.

The lands administered by the District contain many outstanding scenic landscapes. As described in the BLM’s 

Visual Resources Contrast Rating Manual Handbook, visual resources in these landscapes consist of land, water, 

vegetation, and other natural or human-caused features. The BLM is responsible for ensuring that the scenic 

values of public lands are considered before allowing uses that would have negative visual impacts. Scenic values 
Integrated Invasive Plant Management for the Northwest Oregon District

Environmental Assessment

Appendix G: Issues Not Analyzed in Detail

245

are evaluated at the broader viewshed level as viewed from observation points frequented by visitors, not at the 

individual plant level (USDI 1986).

The Oregon FEIS describes that treatments could have short-term negative effects for the first year following 

treatment, but in the long term, effects would be beneficial because of the return of native vegetation (USDI 

2010a:296). The short-term negative effects of treatments would vary based on which herbicide is applied and 

how it is applied but that when herbicides are applied using a backpack sprayer or wicking method, the effect is 

not easily discernable (USDI 2010a:294). The Oregon FEIS did not discuss the effects of aminopyralid, fluroxypyr, or 

rimsulfuron. The effects of these three herbicides were discussed in the 2016 PEIS, which states that impacts to 

visual resources nationwide from a program that included these three herbicides would be similar to the program 

without those three herbicides (USDI 2016a:4-77).

The type of actions and the amount of treatments under all alternatives are wholly within the actions analyzed in 

the 2010 Oregon FEIS and the 2016 PEIS. All Standard Operating Procedures and Mitigation Measures analyzed in 

those documents would be applied to all alternatives. On the Northwest Oregon District, treatments would not be 

noticeable at the viewshed scale; under the action alternatives, 95 percent of herbicide treatments would be spot 

treatments to target specific plants (so that effects to non-target species can be kept to a minimum). When 

broadcast spraying is done, selective herbicides would be used; only target invasive plants would be killed, leaving 

remaining native vegetation unharmed. Standard Operating Procedures (Appendix D) include requirements for 

project designs that blend with topographic forms, do not attract attention, and are restored to repeat existing line 

and color. Because of these measures, herbicide treatments under all alternatives would not result in large patches 

of dead invasive plants that would be noticeable at the landscape (viewshed) level. Due to the temporary nature of 

any discernable visual contrast introduced by invasive plant treatments, conformance with assigned Visual 

Resource Management Class objectives would be ensured, as projects have up to 5 years to come into 

conformance with visual objectives.