INVASIVE EXOTIC PLANT MANAGEMENT PLAN

and

ENVIRONMENTAL ASSESSMENT

Rocky Mountain National Park

Yellow Toadflax in Horseshoe Park

Prepared by:

U.S. Department of the Interior

National Park Service

Rocky Mountain National Park

Colorado

August, 2003
i

Invasive Exotic Plant Management Plan

and

Environmental Assessment

Rocky Mountain National Park

August, 2003

Abstract:

National Parks represent complex communities of native plants and animals. The

ecological balance within these communities is currently threatened by the invasion of

exotic plants. Controlling invasive exotic plants is a serious challenge facing National

Park Service (NPS) managers, who are charged with the protection of natural and cultural

resources. Over one hundred species of exotic plants occur in Rocky Mountain National

Park (RMNP). Of these, 35 species are of particular concern because they are aggressive

and invasive and have the potential to displace native vegetation. RMNP proposes a

proactive approach to manage exotic plant infestations, including mechanical, cultural,

chemical, and biological control techniques. Of the 35 invasive exotic species identified

for control, herbicides will likely be used on only 15 of those species. Citizens and

environmental organizations have expressed concern over chemical control (use of

synthetic herbicides), which prompted the Park to develop a new Invasive Exotic Plant

Management Plan and Environmental Assessment (EA) to replace the Plan and EA

released for public review in February 2000. This Plan and EA addresses those concerns

and examines alternatives for controlling invasive exotic herbaceous plants and grasses,

including lower risk techniques such as scalding exotic plants with hot water (steam), and

using biodegradable natural chemicals that are acceptable herbicides used by organic

farmers. If synthetic herbicides are used, the park would use the least toxic effective

herbicide only after making a good faith effort to control invasive exotics using other

control techniques.

List of Abbreviations

ATV All Terrain Vehicle

BLM Bureau of Land Management

CDOT Colorado Department of Transportation

CDOW Colorado Division of Wildlife

CE Categorical Exclusion

CNAP Colorado Natural Areas Program

CNHP Colorado Natural Heritage Program

DBG Denver Botanical Gardens

DWLOC Drinking Water Level of Comparison

EA Environmental Assessment

ESA Endangered Species Act

FWS U.S. Fish and Wildlife Service

HTP Human Toxicity Potential

IEMP Invasive Exotic Management Plan

IPM Integrated Pest Management
ii

MCS Multiple Chemical Sensitive

MSDS Material Safety Data Sheet

NEPA National Environmental Policy Act

NPS National Park Service

NRCS Natural Resources Conservation Service, U.S. Department of Agriculture

PPE Personal Protective Equipment

RMNP Rocky Mountain National Park

USDA United States Department of Agriculture

USFS United States Forest Service

Definitions

Several terms are defined to facilitate understanding of this Plan and EA:

Native Plant – The NPS defines native plants as all species that have occurred or now occur

as a result of natural processes on lands designated as units of the national park system.

Native species in a place are evolving in concert with each other (NPS 2001). A goal of the

NPS is to perpetuate native plants and animals as part of the natural ecosystem.

Exotic Plant – The NPS defines exotic species as those species that occupy or could occupy

park lands directly or indirectly as the result of deliberate or accidental human activities.

Because an exotic species did not evolve in concert with the species native to the place, the

exotic species is not a natural component of the natural ecosystem at that place (NPS 2001)

Invasive Exotic Plant - An aggressive plant that is known to displace native plant species.

Invasive exotic species are unwanted plants which are harmful or destructive to man or

other organisms (Holmes, 1979; Webster).

State Listed Noxious Weeds – Invasive exotic plants prohibited or restricted by Colorado

Law. Many of the invasive exotic plants known to occur in RMNP fall into this category

(please refer to Table 1 on page 3). Transporting seed or parts of these plants, or allowing

them to seed on one’s property is prohibited. RMNP does propose to control a few invasive

exotic plants that are not State Listed Noxious Weeds because they pose a threat to the

park’s natural resources.

Integrated Pest Management (IPM) - A decision-making process that coordinates

knowledge of pest biology, the environment, and available technology to prevent

unacceptable levels of pest damage, by cost-effective means, while posing the least possible

risk to people, resources, and the environment (NPS, 2001).

Proposed Integrated Pest Management Control Techniques:

Mechanical: Using tools to remove plants by mowing, digging, and cutting seed

heads and plants.

Cultural: Providing competition, stress, or control of exotic species by planting

native vegetation or burning exotic plants.

Chemical: Using synthetic herbicides to kill or severely stress invasive exotic

plants.
iii

Biological: Using insects, mammals or pathogens to stress exotic plants.

Low Risk Methods: Using hot water (steam) to scald exotic plants, or using natural

chemicals that may contain biodegradable soap, acetic acid, sugar compounds, or

plant proteins.
iv

INVASIVE EXOTIC PLANT MANAGEMENT PLAN

And

ENVIRONMENTAL ASSESSMENT

Rocky Mountain National Park, Colorado

Summary

The National Park Service (NPS) is examining ways to manage and control exotic plant

infestations in Rocky Mountain National Park (RMNP). Thirty-five species of invasive,

exotic herbaceous plants and grasses are of concern to park managers (please refer to

Table 1 on page 3). These invasive species, occurring on an estimated 427 acres of park

land, displace natural vegetation and consequently affect the long-term health of native

plant and animal communities. Of the 427 infested acres, 65.25 acres would be managed

using the full range of IPM techniques, including the use of synthetic herbicides.

RMNP released an Invasive Exotic Plant Management Plan (Plan) and Environmental

Assessment (EA) for public review in February 2000. The Plan proposed using IPM

techniques, including mechanical, cultural, synthetic herbicides, and biological controls

to eradicate or reduce exotic plant species. It did not include using low risk methods such

as hot water and natural chemicals that are acceptable herbicides used by organic farmers.

Thirty-eight responses from citizens and environmental organizations were received.

Concerns expressed by respondents focused on the use of synthetic herbicides and their

potential effects on the environment and people. Additionally, some respondents wanted

to be properly notified if, when, and where herbicides were to be used. To address these

concerns RMNP has prepared this new Plan and EA. No synthetic herbicides have been

used in the park for the last two years, and will not be used until a Plan has been

approved.

This new plan and EA examines in detail two alternatives: the continuation of current

management practices and the preferred alternative. The no action alternative was also

evaluated but rejected from further consideration. The preferred alternative will have no

adverse impact on geology and topography; threatened, endangered, candidate species or

species of special concern; natural lightscapes; archeological resources, cultural

landscapes, historic structures, and museum collections; prime and unique farmlands;

ethnographic resources; socioeconomics of the park and nearby communities; or

environmental justice. There would be short-term negligible to minor adverse impacts to

soils and native vegetation; aquatic, wetland and riparian communities; natural

soundscapes; wildlife; recommended wilderness; air quality; human health and safety;

park operations; and visitor use. Weed management activities will be an inconvenience

and will intrude on some visitor’s park experience. These impacts will be adverse, shortterm, localized and minor. There would be long-term beneficial effects to soils and

native vegetation; threatened, endangered, candidate species or rare species; aquatic,

wetland and riparian communities; park operations; and visitor use.
v

RMNP proposes a proactive approach to managing invasive exotic plants. If left

unchecked, invasive exotic plants could spread to unmanageable levels and cause longterm harm to the park’s natural and cultural resources. This Plan provides the blueprint

for managing exotic plants, while fulfilling the NPS mandate of protecting and preserving

natural resources and the human environment. The Plan’s primary objectives are to

eradicate, significantly reduce, or contain populations of thirty-five species of invasive

exotic plants in the park, and to aggressively eradicate any new invasive exotics that may

invade the park in the future. To accomplish this, the Plan calls for the following

actions:

Proposed Actions • Action 1 - Inventory and monitor invasive exotic plants in RMNP.

• Action 2 - Prioritize exotic plants to be controlled.

• Action 3 - Identify control techniques most appropriate for each species.

• Action 4 - Apply the most appropriate control technique for each species.

• Action 5 - Monitor effectiveness of control efforts.

• Action 6 - Prevent new infestations by monitoring invasive exotic plant pathways.

• Action 7 - Inform the public about RMNP exotic plants and control methods.

• Action 8 - Work with adjacent landowners and local, county, state and federal

agencies.

The eradication or control of invasive exotic plants requires an Environmental

Assessment (EA) to evaluate the impacts of alternatives on the park’s natural, cultural,

and human resources. There are many different ways to control invasive exotic plant

species, including digging, mowing and cutting plants, use of prescribed fire, herbicides

(both natural and synthetic), hot water (steam), insects. The effectiveness and

environmental consequences of these techniques, including taking no action, are

examined in this Plan and EA. The alternatives being considered are:

ALTERNATIVE 1 ñ CONTINUATION OF CURRENT MANAGEMENT PRACTICES:

MECHANICAL, CULTURAL, LOW RISK METHODS INCLUDING NATURAL BIODEGRADABLE

HERBICIDES, AND BIOLOGICAL CONTROL (NO SYNTHETIC HERBICIDE CONTROL).

RMNP is currently using these techniques to control invasive exotic plant infestations

within the park. These activities are Categorically Excluded from compliance with

NEPA. If this alternative is selected, RMNP will continue to conduct invasive exotic

plant control work within the park as it has for the past two years, without the use of

synthetic herbicides.

This alternative affords less long-term protection of the Park’s natural resources than the

preferred alternative. Some species like leafy spurge, yellow toadflax, and field bindweed

cannot be effectively controlled without synthetic herbicides. There would be a moderate

risk of losing native flora and fauna due to ineffective eradication of some invasive exotic

plant species.
vi

ALTERNATIVE 2 ñ PREFERRED ALTERNATIVE: MECHANICAL, CULTURAL, LOW RISK

METHODS INCLUDING NATURAL HERBICIDES, BIOLOGICAL AND SYNTHETIC HERBICIDE

CONTROL.

The preferred alternative would implement the full range of IPM techniques –

mechanical, cultural, natural and synthetic chemicals, biological, and low risk methods–

to eradicate or to prevent/reduce further infestations. The control technique(s) would be

selected based on minimizing environmental effects, cost effectiveness, and with the

utmost attention to safety. Only the least toxic effective synthetic herbicides would be

used as a last resort after making a good faith effort to control invasive exotics using

other techniques.

The Preferred Alternative provides park managers with the broadest range of “tools” to

manage invasive exotic plants, and can provide the greatest long-term protection to

natural resources and native biodiversity.

ALTERNATIVE 3 - NO INVASIVE EXOTIC PLANT MANAGEMENT OR CONTROL.

Without management or control, invasive exotic plants would continue to harm the

Park’s natural resources, displacing native vegetation and wildlife. While a “No Action”

alternative must be included in an EA, it does not meet the Park’s enabling legislation to

protect natural resources, the NPS Organic Act (1916), or the Federal Noxious Weed Act

(1974).

This Plan and EA analyzes the alternatives for invasive exotic plant management in

RMNP and their impacts on natural, cultural and human resources. It has been prepared

in compliance with the National Environmental Protection Act (NEPA) of 1969 and

regulations developed by the Council on Environmental Quality (40 CFR 1508.9).
vii

Table of Contents

Abstract: ....................................................................................................................................... i

Summary ..................................................................................................................................... iv

CHAPTER 1 PURPOSE FOR THE PLAN.............................................................................................. 1

Introduction ...................................................................................................................................... 1

Location and Access.............................................................................................................................. 1

Invasive Exotic Plants in RMNP ........................................................................................................... 1

Background .................................................................................................................................... 15

Issue and Impact Topics............................................................................................................................ 17

Impact Topics Dismissed from Further Analysis...................................................................................... 18

Relationship to Other Plans ...................................................................................................................... 18

Compliance with State and Federal Regulations ...................................................................................... 19

Decision Process .................................................................................................................................... 19

CHAPTER 2 NEED FOR THE PLAN AND PROPOSED ACTIONS.................................................. 20

Impacts of Invasive Exotic Plants............................................................................................................. 20

Plan Goals .................................................................................................................................... 20

Plan’s Proposed Actions ........................................................................................................................... 20

ACTION 1 – Inventory and monitor invasive exotic plants in RMNP................................................. 21

ACTION 2 – Prioritize exotic plants to be controlled. .......................................................................... 22

ACTION 3 – Identify control techniques that are most appropriate for each species............................ 24

ACTION 4 – Apply the most appropriate control technique. ................................................................ 29

ACTION 5 – Monitor effectiveness of control efforts........................................................................... 29

ACTION 6 – Prevent new infestations by monitoring exotic plant pathways. ...................................... 30

ACTION 7 – Inform the Public about exotic plants and control measures............................................ 30

ACTION 8 – Work closely with adjacent landowners to achieve common goals of exotic plant

management..................................................................................................................... 31

CHAPTER 3 ALTERNATIVES ............................................................................................................ 33

Alternative 1 – Continuation of Current Management Practices: mechanical, cultural, low risk

methods, natural chemical and biological control (no synthetic herbicide control)....... 33

Alternative 2 – Preferred Alternative: mechanical, cultural, low risk methods, biological and

natural and synthetic chemical control........................................................................... 33

Alternatives Excluded From Further Consideration ................................................................................. 34

Alternative 3 - No invasive exotic plant management or control. ......................................................... 34

Environmentally Preferred Alternative..................................................................................................... 34

CHAPTER 4 AFFECTED ENVIRONMENT........................................................................................ 39

Natural Resources .................................................................................................................................... 39

Topography, Geology and Soils .......................................................................................................... 39

Vegetation ....................................................................................................................................... 39

Natural Soundscape and Lightscape.................................................................................................... 41

Aquatic, Wetland and Riparian Communities ..................................................................................... 41

Endangered, Threatened, and Rare Speices......................................................................................... 42

Wildlife ....................................................................................................................................... 42

Wilderness ....................................................................................................................................... 43

Air Quality ....................................................................................................................................... 43

Cultural Resources.................................................................................................................................... 44

Historic Resources............................................................................................................................... 44

Prehistoric Resources .......................................................................................................................... 44

Human Environment................................................................................................................................. 44

Socioeconomics................................................................................................................................... 44

Visitor Use ....................................................................................................................................... 45

Park Operations ................................................................................................................................... 45
viii

CHAPTER 5 ENVIRONMENTAL CONSEQUENCES ....................................................................... 46

Methodology .................................................................................................................................... 46

Past Actions and Reasonably Foreseeable Activities .......................................................................... 46

Natural Resources .................................................................................................................................... 48

Soils and Native Vegetation ................................................................................................................ 48

Natural Soundscape and Lightscape.................................................................................................... 57

Aquatic, Wetland and Riparian Communities ..................................................................................... 60

Endangered, Threatened and Rare Species.......................................................................................... 66

Wildlife ....................................................................................................................................... 74

Wilderness ....................................................................................................................................... 78

Air Quality ....................................................................................................................................... 82

Cultural Resources.................................................................................................................................... 86

Human Environment................................................................................................................................. 89

Socioeconomics................................................................................................................................... 90

Visitor Experience............................................................................................................................... 93

Human Health and Safety.................................................................................................................... 96

CHAPTER 6 SHORT-TERM USES VERSUS LONG-TERM PRODUCTIVITY ............................. 103

CHAPTER 7 MITIGATION MEASURES .......................................................................................... 104

Mitigation Measures Common to Alternatives 1 and 2 .......................................................................... 104

Mitigation Measures Specific to Alternative 2 ....................................................................................... 105

CHAPTER 8 CONSULTATION and COORDINATION ................................................................... 109

Preparers .................................................................................................................................. 109

List of Agencies and Organizations ........................................................................................................ 109

List of Persons Consulted ....................................................................................................................... 110

LITERATURE CITED............................................................................................................................... 111

APPENDIX A How the Non-Native Plants were Prioritized................................................................... 117

APPENDIX B Proposed Action and Control for 35 Invasive Exotic Plants............................................ 120

APPENDIX C Threshold level for 15 invasive exotic plants that warrant chemical control................... 125

APPENDIX D Endangered, Threatened, and Rare Species of Rocky Mountain National Park.............. 127

APPENDIX E List of sources used by Rocky Mountain National Park to identify endangered,

threatened and rare species that must be protected if found within the proposed

project site. ...................................................................................................................... 133

APPENDIX F Communications Plan for Herbicide Use within RMNP ................................................. 135

APPENDIX G Relative Aquifer Vulnerability Evaluation (RAVE)........................................................ 136

APPENDIX H Biological Control Insects ............................................................................................... 141

APPENDIX I Letter from Colorado Commissioner of Agriculture ....................................................... 142

APPENDIX J Invasive Exotic Plants to Watch for in Colorado............................................................. 143

APPENDIX K Reference Material for Behavior of Synthetic Herbicides in the Environment ............... 144

APPENDIX L U.S. Fish & Wildlife Service Correspondence ................................................................ 146

List of Tables

Table 1 - Invasive Exotic Plants of Colorado ................................................................................................ 3

Table 2 - Exotic Plants by Treatment Area and Zone Designation.............................................................. 12

Table 3 - List of different habitats, estimated acres and risk level for invasion by exotic plants within

RMNP .......................................................................................................................................... 15

Table 4 - Estimated Herbicide Treatment Schedule for 15 Invasive Exotic Plants ..................................... 28

Table 5 - Comparative Summary of Environmental Impacts ...................................................................... 35

Table 6 - Behavior of Synthetic Herbicides in Soil and Effects on Target and Non-target Plants .............. 53

Table 7 - Behavior of Synthetic Herbicides in Aquatic, Wetland, and Riparian Communities................... 63

Table 8 - Impact of Synthetic Herbicides on Threatened, Endangered and Rare Species ........................... 71

Table 9 - Impact of Synthetic Herbicides on Air Quality ............................................................................ 84

Table 10 - Estimated Initial Treatment Cost for Synthetic Chemical Control.............................................. 92

Table 11 - Impact of Synthetic Herbicides on Human Health...................................................................... 98
ix

List of Figures

Figure 1 - Index of Treatment Areas ............................................................................................................. 6

Figure 2 - Treatment Areas ........................................................................................................................... 7

Figure 3 - Treatment Areas ........................................................................................................................... 8

Figure 4 - Treatment Areas ........................................................................................................................... 9

Figure 5 - Treatment Areas ......................................................................................................................... 10

Figure 6 - Treatment Areas ......................................................................................................................... 11
1

CHAPTER 1 PURPOSE FOR THE PLAN

Because of the complexity of this management plan and EA, the purpose and need for

the plan have been divided into two chapters. Chapter 1 describes the purpose for the

plan and Chapter 2 the need for the plan and the proposed actions that would be

implemented if the plan were adopted.

Introduction

Congress established Rocky Mountain National Park on January 26, 1915. The park’s

enabling legislation states, "...said area is dedicated and set apart as a public park for

the benefit and enjoyment of people of the United States...with regulations being

primarily aimed at the freest use of the said park for recreation purposes by the public

and for the preservation of the natural conditions and scenic beauties..." (38 Stat. 798).

The significance of RMNP lies in displaying, preserving and making available for

public use and enjoyment, some of the finest examples of the spectacular

physiographic, biologic, and scenic features typifying the southern Rocky Mountains.

These natural and historic resources are even more significant because of their

proximity to Colorado's Front Range metropolitan areas. Minimizing impacts to the

natural environment, but yet still providing recreational opportunities for the public is

consistent with the park’s enabling legislation.

NPS superintendents are expected to vigorously apply existing legislation, executive

orders, and NPS regulatory standards in managing exotic plants (Please refer to

Compliance with State and Federal Regulations on Page 19). The most fundamental

provisions are found in the NPS Organic Act of 1916 (16 USC Section 1) and the

Redwood Act amendment to the 1970 General Authorities Act (16 USC Section 1a-1).

Specifically, NPS Director’s Order #12, amended in January 2000, directs national park

units to develop individual Exotic Plant Management plans in compliance with the

National Environmental Policy Act (NEPA).

Location and Access

RMNP, located in north central Colorado, encompasses 265,780 acres. The park lies

within Larimer, Boulder, and Grand Counties and is bordered by the towns of Estes

Park, Allenspark, and Glenhaven on the east and Grand Lake on the west. The park is

surrounded by state, local, private, and federally owned lands. About 62% of the park

borders national forest land, of which 70% is managed as wilderness.

The park is easily accessible from the Denver metropolitan area, 65 miles to the

southeast. Interstates 25, 70 and 76, which converge in Denver, provide access for

visitors coming from all regions of the United States. Local thoroughfares accessing

the park include State Highways 7, 34, and 36. RMNP’s proximity to populous Front

Range communities has resulted in steadily increasing visitation. RMNP receives

nearly 3.5 million visitors annually, roughly equal to Yellowstone’s visitation, though it

is about one-eighth the size of the country’s first national park.

Invasive Exotic Plants in RMNP

Controlling exotic plant infestations is one of the most serious challenges facing RMNP

managers, who are charged with the protection of natural and cultural resources.
2

Invasive exotic plants are infesting RMNP at an alarming rate. Of over one hundred

exotic herbaceous plants and grasses occurring in the park, 35 species have been

identified as a threat to the park’s natural resources (please refer to Table 1 on page 3).

An estimated 427 acres below 8,500 feet elevation are affected by these 35 species

(please refer to Figures 1 through 6 on pages 6 through 11 for maps of the proposed

treatment areas and currenr locations of invasive exotic plants within the park).

The dots that are shown on Figures 2 through 6 represent existing invasive exotic plant

infestations that are being considered for natural and synthetic herbicide treatments.

Herbicide treatment would continue until the infestations can be brought below

specified threshold levels, which is anticipated to take between three to five years. The

dots are generic and represent one of the 15 invasive exotic species identified for

control using herbicides. Each treatment area surrounding the dots represents areas of

the park infested with invasive exotic plants that are to be controlled using all of the

various IPM techniques. Table 2, on pages 12 - 14, identifies the invasive exotic

species that are present and will be controlled within each treatment area. Control work

will not be done on park inholdings, which are privately owned. Species listed in Table

2 that will be controlled using herbicides have been identified with an asterisk. Other

species will be controlled using IPM techniques other than herbicides.

Although, 427 acres represents less than 1% of the landmass within the park, 17 % of

the park’s landmass (45,044 acres) is believed to be at high or medium risk of

infestation (please refer to Table 3 on page 15). Even the alpine tundra (11,500 feet

elevation and above) – an outstanding feature of Rocky Mountain National Park – is

now considered at medium risk of infestation. Previously, high altitude was believed

to be a natural barrier for exotic plant infestations. It is primarily due to the park’s

proactive approach in controlling invasive exotics that more acres have not become

infested (i.e. controlling plants before they become a serious problem).

Exotic plants near park boundaries threaten to infest neighboring lands and

communities. Conversely, where neighboring landowners are not controlling exotic

plants, these invasive species can spread into the park. RMNP must work closely with

local citizens, organizations, communities, neighboring counties, the state, and adjacent

federal landowners to achieve common goals of managing invasive exotic plants.

If action is not taken, invasive exotic plants will displace native vegetation and wildlife

habitat will be lost. In addition, biological diversity, soils, aquatic systems, and rare,

threatened, and endangered species could be affected. Visitor enjoyment of park

resources may also be diminished if exotic plants are not controlled.

Natural Resource Integrity and Biodiversity ñ When exotic plant species displace or

inhibit the growth of native vegetation in RMNP, there are long-term changes to plant

communities. Natural habitat and diversity of flora and fauna are diminished:
3

• Wildlife Habitat ñ Exotic plants are undesirable –and in some cases, poisonous

food for wildlife. For example, in Moraine Park, which is critical elk winter and

calving range, 20% of the plant composition is exotic. This elk habitat could be lost

if some exotic plants continue to spread.

• Wildflowers – Some exotic plants inhibit the growth of native wildflowers – a

major attraction for park visitors – reducing the aesthetic qualities of the landscape.

Native insects that rely on wildflowers are also affected.

• Soil Erosion – When native vegetation is displaced by exotics, the amount of bare

ground increases, which consequently increases soil erosion.

• Cultural Resources ñ Exotic plants may alter the integrity of historic or cultural

landscapes.

• Public Health ñ Some exotic plant species contain toxins that can be harmful to

humans after prolonged exposure. For example, leafy spurge, spotted knapweed

and diffuse knapweed contain toxins that can affect people with sensitive skin.

• Neighbor Relations – As exotic plant species cross the park boundary (by either

moving into or out of the park) relationships between the park and neighboring

landowners can be strained.

Table 1 - Invasive Exotic Plants of Colorado

INVASIVE EXOTIC SPECIES

PRESENT

IN THE

PARK

ë95-í96 RISK

ASSESSMENT

SPECIES OF

CONCERN

PROPOSED

FOR

CONTROL

STATE

NOXIOUS

WEED

LIST

African rue (Peganum harmala) ■

Baby’s breath (Gypsophilia paniculata) ■■ ■

Black henbane (Hyoscyamus niger) ■

Black knapweed (Centaurea nigra) ■

Black nightshade (Solanum nigrum) ■

Blue mustard (Chorispora tenella) ■

Bouncingbet (Saponaria officinalis) □ ■■

Bull thistle (Cirsium vulgare) ■■ ■■

Camelthorn (Alhagi pseudalhagi) ■

Canada thistle (Cirsium arvense) ■■ ■■

Cheatgrass (Bromus tectorum) ■■ ■ (limited)

Chicory (Cichorium intybus) ■

Chinese clematis (Clematis orientalis) ■

Coast tarweed (Madia sativa) ■

Common burdock (Arctium minus) ■ ■■

Common groundsel (Senecio vulgaris) ■

Common mullien (Verbascum thapsus) ■ ■■

Common St. Johnswort (Hypericum perforatum) □■ ■■

Common tansy (Tanacetum vulgare) ■

Common teasel (Dipsacus sylvestris) ■

Curly dock (Rumex crispus) ■ ■ (limited)

Cypress spurge (Euphorbia cyparissias) ■

Dalmatian toadflax (Linaria dalmatica) ■■ ■■

Dame’s rocket (Hesperis matronalis) □ ■■

Deptford pink (Dianthus armeria L.) ■ ■
4

INVASIVE EXOTIC SPECIES

PRESENT

IN THE

PARK

ë95-í96 RISK

ASSESSMENT

SPECIES OF

CONCERN

PROPOSED

FOR

CONTROL

STATE

NOXIOUS

WEED

LIST

Diffuse knapweed (Centaurea diffusa) ■■ ■■

Dyers woad (Isatis tinctoria) ■

Field bindweed (Convolulus arvensis) ■■ ■■

Flixweed (Descurainia sophia) ■

Green foxtail (Setaria viridis) ■

Hairy nightshade (Solanum sarrachoides) ■

Halogeton (Halogeton glomeratus) ■

Hoary alyssum (Berteoa incana) ■ ■

Hoary cress (Cardaria draba) ■

Houndstongue (Cynoglossum officianale) ■ ■■

Johnsongrass (Sorghum halepense) ■

Jointed goatgrass (Aegilops cylindrica) ■

Kentucky bluegrass (Poa pratensis) ■■ ■ (limited)

Kochia (Kochia scoparia) ■

Leafy spurge (Euphorbia esula) ■■ ■■

Longspine sandbur (Cenchrus longispinus) ■

Mayweed chamomile (Anthemis cotula) ■

Mediterranean sage (Salvia aethiopis) ■

Musk thistle (Carduus nutans) ■■ ■■

Myrtle spurge (Euphorbia mysinites) ■

Orange hawkweed (Hieracium aurantiacum) ■ ■■

 Orchard grass (Dactylis glomerata) ■ ■

Oxeye daisy (Chrysanthemum leucanthemum) ■■ ■■

Perennial pepperweed (Lepidium latifolium) ■

Plumeless thistle (Carduus acanthoides) ■

Poison hemlock (Conium maculatum) ■ ■

Puncturevine (Tribulus terrestris) ■

Purple loosestrife (Lythrum salicaria) ■ ■

Quackgrass (Agropyron repens) ■■ ■■

Redstem filaree (Erodium cicutarium) ■

Red-top grass (Agrostis gigantea) ■ ■ (limited)

Reed canary grass (Phalaris arundinaceae) ■ ■

Rush skeletonweed (Chondrilla juncea) ■

Russian knapweed (Centaurea repens) ■

Russian thistle (Salsola collina) ■ ■■

Russian thistle (Salsola iberica) ■

Common Russian thistle (Salsola australis) ■ ■

Saltcedar (Tamarix parviflora) ■

Saltcedar (Tamarix ramosissima) ■

Scentless chamomile ( Matricaria perforata) ■ ■■

Scotch thistle (Onopordum acanthium) ■

Scotch thistle (Onopordum tauricum) □ ■■

Sheep fescue (Festuca ovina) ■ ■ (limited)

Smooth brome (Bromus inermis) ■■ ■

Swamp sow-thistle (Sonchus uliginosus) ■ ■

Spotted knapweed (Centaurea maculosa) ■■ ■■

Squarrose knapweed (Centaurea virgata) ■

Sulfur cinquefoil (Potentilla recta) ■ ■■
5

INVASIVE EXOTIC SPECIES

PRESENT

IN THE

PARK

ë95-í96 RISK

ASSESSMENT

SPECIES OF

CONCERN

PROPOSED

FOR

CONTROL

STATE

NOXIOUS

WEED

LIST

Timothy (Phleum pratense) ■ ■ (limited)

Velvetleaf (Abutilon theophrasti) ■

White sweetclover (Melilotus alba) ■■ ■

Wild caraway (Carum carvi) ■

Wild mustard (Brassica kaber) ■

Wild proso millet (Panicum miliaceum) ■

Yellow foxtail (Setaria glauca) ■

Yellow nutsedge (Cyperus esculentus) ■

Yellow starthistle (Centaurea solstitialis) ■

Yellow sweetclover (Melilotus officianalis) ■■ ■

Yellow toadflax (Linaria vulgaris) ■■ ■■

□ = Historic but currently eradicated from the park

Species listed in bold = Top ten prioritized weed species for the State of Colorado.

These ten species are acknowledged to be the most widespread and to cause the greatest

economic impact in the state.

(limited) = Only a small percentage of the infestation will be controlled in the park,

usually near the park boundary.
6

Figure 1 ñ Index of Treatment Areas
7

Figure 2 - Treatment Areas
8

Figure 3 - Treatment Areas
9

Figure 4 - Treatment Areas
10

Figure 5 - Treatment Areas
11

Figure 6 - Treatment Areas
12

Table 2 - Exotic Plants by Treatment Area and Zone Designation

Allenspark Area (Natural Zone) ñ

Figure 5

Canada thistle

Musk thistle

Aspenbrook Drainage (Natural Zone) ñ

Figure 5

Dalmatian toadflax

Musk thistle

Aspenglen Campground (Developed

Zone) ñ Figure 3

Canada thistle

Common burdock

Dalmatian toadflax

Field bindweed

Houndstongue

Musk thistle

Spotted knapweed

Wooly mullien

Yellow sweetclover

Yellow toadflax

Bear Lake Road (Developed Zone) ñ

Figures 4 & 5

Baby’s breath

Canada thistle

Spotted knapweed

Wooly mullien

Yellow sweetclover

Yellow toadflax

Beaver Meadows Entrance (Developed

Zone) ñ Figure 4

Canada thistle

Dalmatian toadflax

Diffuse knapweed

Field bindweed*

Musk thistle

Russian thistle

Wooly mullien

Yellow toadflax*

* Proposed for herbicide control

Beaver Point (Natural Zone) ñ

Figure 4

Baby’s breath

Canada thistle*

Dalmatian toadflax

Diffuse knapweed

Field bindweed*

Wooly mullien

Yellow toadflax*

Black Canyon (Natural & Developed

Zone) ñ Figure 2

Bull thistle

Canada thistle

Diffuse knapweed

Hoary alyssum

Houndstongue

Leafy spurge

Musk thistle

Spotted knapweed

Wooly mullien

Yellow toadflax

Cow Creek Drainage (Natural Zone) ñ

Figure 2

Canada thistle

Houndstongue

Leafy spurge*

Musk thistle

Wooly mullien

Deer Mountain (Natural Zone) ñ

Figure 3

Musk thistle

Endovalley (Developed & Natural

Zones) ñ Figure 3

Canada thistle

Houndstongue

Leafy spurge

Musk thistle

Orange hawkweed

Wooly mullien

Yellow sweetclover

Yellow toadflax*
13

Fall River Entrance (Developed Zone) ñ

Figure 3

Leafy spurge*

Musk thistle

Fall River Road (Developed Zone) ñ

Figure 3

Canada thistle*

Leafy spurge*

Musk thistle

Yellow sweetclover

Yellow toadflax*

Glacier Basin Campground (Developed

Zone) ñ Figure 4

Canada thistle

Curly dock

Musk thistle

Russian thistle

Yellow toadflax

Hallowell Park (Developed & Natural

Zone ñ Figure 4

Canada thistle

Deptford pink

Musk thistle

Field bindweed

Sulfur cinquefoil

Yellow toadflax

Headquarters/Utility Area (Historic

Zone) ñ Figure 4

Canada thistle*

Dalmatian toadflax

Field bindweed*

Hoary alyssum

Houds toungue

Leafy spurge*

Musk thistle

Russian thistle

Wooly mullien

Yellow sweetclover

Yellow toadflax*

Hidden Valley (Developed Zone) ñ

Figure 3

Curly dock

Yellow toadflax

High Drive (Developed Zone) ñ Figure 4

Canada thistle

Dalmatian toadflax

Diffuse knapweed

Yellow toadflax

Hondius Park (Natural Zone) ñ Figure 3

Leafy spurge

Yellow toadflax

Canada thistle*

Musk thistle

Horseshoe Park (Natural Zone) ñ

Figure 3

Canada thistle

Leafy spurge*

Musk thistle

Yellow toadflax*

Lawn Lake Trail (Natural Zone) ñ

Figure 3

Canada thistle

Musk thistle

Lily Lake/Twin Sisters (Developed Zone)

ñ Figure 5

Canada thistle

Musk thistle

Yellow toadflax

Little Horseshoe Park (Natural Zone) ñ

Figure 3

Canada thistle

Musk thistle

Lumpy Ridge/Gem Lake (Natural,

Developed & Historic Zone) ñ Figure 2

Canada thistle

Field bindweed

Houndstongue

Musk thistle

Wooly mullien

Yellow toadflax

McGraw Ranch (Developed Zone) ñ

Figure 2

Canada thistle*

Houndstongue

Leafy spurge*

Musk thistle

Wooly mullien

* Proposed for herbicide control
14

Moraine Park (Natural & Developed

Zone) ñ Figure 4

Bull thistle

Canada thistle

Dalmatian toadflax

Field bindweed*

Musk thistle

Sulfur cinquefoil*

Wooly mullien

Yellow toadflax*

Moraine Park Campground (Developed

Zone) ñ Figure 4

Canada thistle

Curly dock

Diffuse knapweed

Field bindweed*

Houndstongue

Musk thistle

Spotted knapweed

Wooly mullien

Yellow toadflax

Sand Beach Lake (Natural Zone) ñ

Figure 5

Curly dock

Musk thistle

Wooly mullien

Sprague Lake (Developed Zone) ñ

Figure 4

Canada thistle

Musk thistle

Wooly mullien

Trail Ridge Road ñ East (Developed

Zone) ñ Figure 6

Curly dock

Dalmatian toadflax

Yellow toadflax

Trail Ridge Road ñ West (Developed

Zone) ñ Figure 6

Canada thistle

Curly dock

Oxeye daisy

Scentless chamomile

Yellow sweetclover

Yellow toadflax

Upper Beaver Meadows (Developed &

Natural Zones) ñ Figure 4

Canada thistle

Field bindweed

Leafy spurge*

Musk thistle

Wooly mullien

Yellow toadflax

Westside Trails (Natural Zone) ñ

Figure 6

Bull thistle

Canada thistle

Scentless chamomile

Wild Basin (Developed & Natural Zones)

ñ Figure 5

Canada thistle

Curly dock

Diffuse knapweed

Musk thistle

Spotted knapweed

Wooly mullien

Yellow toadflax

* Proposed for herbicide control
15

Table 3 - List of different habitats, estimated acres and risk level for invasion by

exotic plants within RMNP

Description Acres Percent Cover Risk

Alpine Tundra 33,247 12.50 Medium

Aspen 1499 0.56 High*

Alpine Willows 4630 1.74 Low

Douglas Fir 4065 1.53 Low to Medium*

Dry Grasses 2009 0.76 High*

Dry Shrub 801 0.30 High*

Limber Pine 2687 1.01 Low

Lodgepole Pine 55,665 20.94 Medium*

Disturbed 136 0.05 High*

Rock 48,437 18.22 Low

Ponderosa Pine 9179 3.45 High*

Riparian Bog 345 0.13 Medium

Open Water 1149 0.43 Low

Riparian Meadows 4642 1.75 High*

Blue Spruce 188 0.07 Medium to High*

Riparian Willow 3338 1.26 High*

Snow/Permanent Ice 483 0.18 N/A

Spruce/Fir 93,265 35.09 Low to Medium*

* = Susceptible to invasive exotic plants if a disturbance occurs such as from fire, heavy

ungulate grazing, construction causing vegetation and soil loss, or from social trails.

Background

Native plant communities in what is now RMNP have been evolving over thousands of

years. Plant communities that are presently found in the park were established within

the past 10,000 years as glaciers retreated. The first plants that are considered exotic to

RMNP were introduced by early settlers in the mid-1850’s, who planted exotic grasses

as forage for domestic livestock. Building the infrastructure of the park, such as roads,

trails, campgrounds, visitor centers, and picnic areas further contributed to the

establishment of exotic plant species as seeds were carried in and transported on

machinery, in gravel, or contaminated seed mixes. Over the years, park development

activities have imported contaminated topsoil, exotic seeds, and sod. Visitors, too, have

unknowingly introduced and transported seeds on vehicles, horses, hiking boots, and by

other means.

People, machinery, vehicles, livestock, wildlife, wind, and water have all contributed to

the establishment and spread of exotic plant species.

RMNP began controlling exotic plant species based on two management concerns: 1)

maintenance of native plant ecosystems; and 2) perpetuation of a good neighbor policy.

Exotic plant species near park boundaries were spreading onto adjacent public lands

and communities.

Exotic plant control in RMNP began in 1960. Efforts focused on eradication of Canada

thistle and leafy spurge using synthetic herbicides. By 1999, control efforts had

expanded to include removal of musk thistle, yellow and dalmatian toadflax, diffuse

and spotted knapweed, leafy spurge, bull thistle, scotch thistle, common burdock,
16

houndstongue, hoary alyssum, orange hawkweed, and wooly mullein. The full range of

IPM techniques was used, including pulling, digging, mowing, spraying with synthetic

herbicides, replanting native vegetation, and release of biocontrol insects.

Overall, herbicide use in the park has been limited. During the past ten years, less than

20 acres have been treated with herbicides. Some areas have been treated with

herbicides more than once, but only 20 acres have received one or more chemical

applications. Chemical applications were focused on the eradication of leafy spurge,

Canada thistle, orange hawkweed and diffuse and spotted knapweed.

In addition to digging, cutting, mowing, and using herbicides, other techniques have

been attempted. Biological techniques have been used with limited success. Goats

were introduced into the Cow Creek area of RMNP in 1989 to control leafy spurge with

initial success until the goats threatened the health of nearby native bighorn sheep

herds. That effort was abandoned after one year. Insects have been used for biological

control in the park including an inadvertent introduction of an exotic insect that is

currently threatening two species of native thistle (Louda et al. 1997, 1998). Approved

insect releases to control leafy spurge occurred in 2001 and 2002. In the 1990’s,

revegetation of disturbed areas using native plants became a significant part of

management efforts to reduce exotic plant infestations in the park (McLendon and

Redente, 1994).

In February of 2000, the NPS developed an Invasive Exotic Plant Management Plan

and EA to guide park managers in controlling and/or reducing further infestations of

exotic plants in RMNP. The Plan called for a proactive approach in managing exotic

plant species, using the full range of IPM techniques. During the public review period

for the Plan and EA, thirty-eight responses were received. Some respondents expressed

concern about the potential environmental and safety effects of herbicides as a method

to control exotic plants. Due to these concerns, the Plan was not approved and park

staff began to develop a new Plan to better quantify the effects of exotic plant control

measures on the park’s natural, cultural, and human resources. Synthetic herbicides

have not been used in the park since 2000.

The Commissioner of Agriculture for the State of Colorado wrote a letter to the park

Superintendent dated October 15, 2002 (please refer to Appendix I on page 142)

expressing concern about the length of time it has taken for the park to complete an

Exotic Plant Management Plan. The Commissioner stated that the park’s failure to

complete an EA for weed management was hindering the implementation of an

effective weed management program. The Commissioner urged the park to complete

an Exotic Plant Management Plan and EA by April 1, 2003.

New research conducted in the park and on-the-ground surveys continue to provide

information to park managers on the ecological characteristics of exotic plant and grass

species, the extent of their infestations, and the most effective measures to control and

eradicate them (Wolf 2000, Azdeh 2001, Stohlgren et.al. 1996, 1997a,b,c, 1999, Chong

2002, Kalkan et.al. 2000, RMNP Resources Management Division Annual Reports

2000, 2001, and 2002). The results have been evaluated and integrated into exotic

plant management in the park.
17

Three management zones were identified in the 1976 Park Master Plan: Natural,

Historic, and Developed. Any action called for in this Plan will be consistent with

activities allowed within each of the zones.

Issue and Impact Topics

RMNP has worked closely with universities, U.S.G.S. Biological Resources Division,

exotic plant management experts, adjacent landowners, Colorado Coalition for

Alternatives to Pesticides, and local communities to identify issues, concerns, and

solutions to invasive exotic plant management in RMNP. Additionally, an Invasive

Exotic Plant Management Plan and EA was released in February of 2000 to solicit

public input on a wide range of topics related to exotic plant eradication and control. A

summary of the issues that are considered in detail in this Plan and EA are listed below.

Soils and Native Vegetation

How will using a full range of IPM techniques to control invasive exotic plants affect

soil resources in the park? How will the use of herbicides (natural and synthetic) and

lower risk techniques, such as scalding with hot water (steam) affect native vegetation?

For example, will treating leafy spurge with herbicides denude areas of native broadleaf plants and warm-season grasses? Will insects released on invasive exotic species,

such as knapweed and leafy spurge, adversely affect closely related native species?

How will the various IPM techniques affect rare plants in Rocky Mountain National

Park?

Aquatic, Wetland and Riparian Communities

Will the use of herbicides contaminate ground and/or surface water in areas of

treatment? Will fish, boreal toads and aquatic populations be placed at risk? Will the

use of herbicides contaminate wetland soils or affect flora or fauna in areas of

treatment?

Natural Soundscape

Will exotic plant control activities create noise impacts to the natural soundscapes?

Endangered, Threatened and Rare Species

Will exotic plant control activities, including the use of herbicides, have an impact on

endangered, threatened or rare plant and animal species?

Wildlife

Does the presence of invasive exotic weeds have an impact on wildlife? Will exotic

plant control activities, including the use of herbicides, impact wildlife?

Wilderness

Are there restrictions on the types of exotic plant management techniques that can be

used within recommended wilderness areas of the park? Will exotic plant management

activities affect wilderness?

Air Quality

Will the use of herbicides or other control techniques affect air quality?
18

Cultural Resources

Will mechanical control techniques impact sensitive archeological resources or historic

structures?

Socioeconomics

What would be the economic impact if exotic plants continued to spread within the

park? If park visitors are made aware that herbicides are proposed for use in the park,

would it deter some people from visiting the park?

Visitor Experience

How would invasive exotic plant management activities affect the experience of park

visitors?

Human Health and Safety (Herbicides)

How would chemical applications affect human health? What is the risk of exposure to

carcinogens through respiratory, dermal or dietary routes (touching or eating berries

with residues)? What is the human toxicity potential when chemicals are released into

the air and water?

Impact Topics Dismissed from Further Analysis

Prime and Unique Farmland

In August, 1980, the Council on Environmental Quality (CEQ) directed that federal

agencies must assess the effects of their actions on farmland soils classified by the U.S.

Department of Agriculture’s Natural Resource Conservation Service as prime or

unique. Prime or unique farmland is defined as soil which particularly produces

general crops such as fruits, vegetables, and nuts. According to the Colorado

Department of Agriculture, the soils comprising RMNP are used for wildlife habitat

and are not considered to be prime or unique farmlands. Thus, the topic of prime and

unique farmland will not be addressed as an impact topic.

Natural Lightscapes

Exotic plant control activities will have no impact on natural lightscapes since all work

will occur during daylight hours. This impact topic is dismissed from further

consideration.

Ethnographic Resources, Cultural Landscapes, Historic Structures and Museum

Collections

Exotic plant control activities will have no impact on ethnographic resources, cultural

landscapes, historic structures and museum collections.

Relationship to Other Plans

This Plan, which proposes using the full range of IPM techniques to manage invasive

exotic plants, is consistent with the following park documents:

• Master Plan (1976)

• Land Protection Plan (1985/1991)
19

• Resources Management Plan (1998)

• Backcountry/Wilderness Management Plan (2001)

• Vegetation Restoration Management Plan (1994)

Compliance with State and Federal Regulations

The Plan is consistent with the following Acts, NPS Management Guidelines and

Policies, and Executive Orders.

• Act of 1915, establishing Rocky Mountain National Park

• The National Park Service Organic Act of 1916

• The Redwood Act of 1978

• The Endangered Species Act

• The Wilderness Act of 1964

• National Environmental Policy Act of 1969

• National Park Service Management Policies

• Colorado Noxious Weed Act, 1996

• NPS-77 Natural Resources Management Guidelines

• Act of Administration, 1970

• Federal Noxious Weed Act of 1996

• Carlson-Foley Act of 1968

• Clean Water Act of 1972

• Executive Orders and Director’s Orders

- Federal Water Pollution Control Act and Executive Order 11990 Protection of

Wetlands

- Director’s Order #77-1: Wetland Protection Order of 1998

- Invasive Species Executive Order 13112 of 1999

- Director’s Order #55: Interpreting the National Park Service Organic Act

Decision Process

An EA analyzes the proposed action and alternatives and their impacts on the

environment, cultural resources, and socioeconomics. This EA has been prepared in

accordance with the National Environmental Policy Act (NEPA) of 1969 and

regulations of the Council on Environmental Quality (40 CFR 1508.9). The EA will be

released to the public for a 30-day (minimum) comment period. The NPS will

determine whether the environmental consequences of the proposed action requires

preparation of an Environmental Impact Statement (EIS) or a Finding of No Significant

Impact (FONSI).

This EA evaluates three alternatives and the potential impacts that could result from

implementing each of the alternatives. Chapter 2 describes the Need for the Plan and

the Proposed Actions. Chapter 3 describes the Alternatives, including a “No Action”

alternative. Chapter 4 discusses the Affected Environment, and Chapter 5 includes an

analysis of the Environmental Consequences for each of the alternatives.
20

CHAPTER 2 NEED FOR THE PLAN AND PROPOSED ACTIONS

A Plan is needed to guide RMNP managers in containing, suppressing, or eradicating

invasive exotic plant populations in RMNP.

Impacts of Invasive Exotic Plants

Today, exotic plants infest approximately 2.6 million acres in the national park system,

reducing the natural diversity of these places (NPS, 2002). Invasive exotic plants are

aggressive and competitive. They displace native vegetation by robbing moisture,

nutrients and sunlight from surrounding plants. Exotic plants often establish

themselves in disturbed areas, such as roads, trails, campgrounds, picnic areas, parking

lots and construction sites. Once established, they spread into undisturbed areas.

Overall, native habitat is lost and soil erosion increases, leading to long-term changes in

plant communities and loss of biodiversity. In the state of Colorado, 82 invasive

exotics have infested two million acres of private land and 4.3 million acres of public

land and cost landowners $100 million annually in lost productivity. Invasive exotic

plants have displaced 10% of Colorado’s 1,300 known native vascular plants (Eric

Lane, personal communication).

Plan Goals

The goals of the Invasive Exotic Management Plan are to:

• Eradicate, significantly reduce, or contain populations of 35 invasive exotic plants.

• Prevent further infestations of existing and eradicated species, or new infestations

of invasive exotic species that presently do not exist in the park.

RMNP proposes to be proactive verses reactive by stopping invasive exotic plants

before they become a serious threat to the park’s natural and cultural resources. When

the use of synthetic herbicides is warranted, RMNP proposes to use the least toxic

effective herbicide only as a last resort, and only after making a good faith effort to

control invasive exotics by using other IPM techniques.

Planís Proposed Actions

The Plan calls for eight proactive strategies to achieve the goal of eradication and/or

reduction of invasive exotic species in RMNP. These actions are:

• Action 1 - Inventory and monitor invasive exotic plants in RMNP.

• Action 2 - Prioritize exotic plants to be controlled.

• Action 3 - Identify control techniques most appropriate for each species.

• Action 4 - Apply the most appropriate control technique for each species.

• Action 5 - Monitor effectiveness of control efforts.

• Action 6 - Prevent new infestations by monitoring invasive exotic plant pathways.

• Action 7 - Inform the public about RMNP exotic plants and control methods.

• Action 8 - Work with adjacent landowners and local, county, state and federal

agencies.

These eight actions constitute the Invasive Exotic Plant Management Plan, and are

discussed in detail below.
21

ACTION 1 ñ Inventory and monitor invasive exotic plants in RMNP

This action calls for the continuation of a rigorous inventory and monitoring program in

RMNP. Information gathered from the inventory and monitoring program will be

evaluated and integrated into the exotic plant management program in the park.

Tools: RMNP currently uses Global Positioning System (GPS) equipment to locate and

Geographical Information System (GIS) software to map invasive exotic plants.

Figures 1 through 6 on pages 6 - 11 were developed using the park’s GPS and GIS

capabilities. Maps of each treatment area showing specific locations of invasive exotic

plants are maintained in the Division of Resources Management and Research. Remote

sensing using satellite imagery to locate and map infestations, or spatial modeling

(Kalkan et.al., 2000) may be used in the future.

Inventory and Monitoring: Park staff and volunteers conduct invasive exotic plant

surveys every year, documenting species present and population size (RMNP

Resources Management Division Annual Reports 2000, 2001, and 2002). These annual

surveys include road shoulders and hiking trails in the park. If time allows, they survey

backcountry areas and notify resource managers of any new infestations. Rangers are

trained to identify invasive exotic plants and are instructed to report them to the

Division of Resource Management and Research. Each District Ranger’s “performance

standards” call for the identification and control of invasive exotic plants within their

district (Government Performance and Results Act).

Ongoing surveying and monitoring efforts include:

Stohlgren et. al. (1997a,b,c, 1999) established 181 permanent plots in various habitats

in RMNP. Researchers report the occurrence of invasive exotic plants found within

their plots (Chong 2002, Kalkan, 2000).

Denver Botanical Gardens (DBG): Since 1999, RMNP has contracted with DBG to

survey and map the locations of 86 locations of rare plants in RMNP. Invasive exotic

plants found in or near rare plant populations are reported to the Division of Resources

Management and Research (DBG, 2000).

RMNP’s Fire Effects Monitoring Program has established 69 fire effects plots. Staff is

instructed to notify the Division of Resources Management and Research if any of the

35 invasive exotic plants are encountered, or if monitoring detects an increase or

decrease in the number of exotic plants after a prescribed or wildland fire. In addition,

the park is currently updating its vegetation map and in 2002 approximately 640

vegetation plots were established that documented exotic plants.

RMNP continues to monitor areas where exotic plants have been removed. Permanent

plots are established at selected locations for more intensive sampling of vegetative

cover and density to determine the effectiveness of control techniques (RMNP

Resources Management Division Annual Report 2002). Plot protocols were borrowed

from the NPS Fire Monitoring Handbook procedures and the USDA-USFS Field Guide

for Invasive Plant Inventory, Monitoring and Mapping Protocol.
22

ACTION 2 ñ Prioritize exotic plants to be controlled.

RMNP prioritizes invasive exotic plants for control based on two management

strategies: the Risk Assessment (Rutledge and McLendon, 1996) and Management

Zones (RMNP Master Plan, 1976). RMNP also relies on new information as it

becomes available about the invasive tendencies of species, and considers state or

national priorities when setting park priorities.

Risk Assessment:

In 1995 and 1996, Rutledge and McLendon of Colorado State University conducted

a risk assessment of 102 exotic plant species known to occur in RMNP. Due to an

increase in inventory and monitoring of exotic plants since 1996, the current list of

exotic plants known to occur in the park has expanded to 115. Park staff will

continue to use the Rutledge and McLendon risk assessment methodology to

establish priorities for exotic plant control.

The Rutledge and McLendon risk assessment evaluates exotic plants based on their

ecological impact and their relative ease of control. Exotic plant species were

assigned “urgency” scores, ranging from high (delayed action will result in

significant effort required for control), to medium (delayed action will result in a

moderate increase in the effort for control), to low (delayed action will result in

little increase in effort required for control). High-ranking plants – those that have a

potential ecological impact score of 24 in the Risk Assessment – will be the highest

priority for control. (See Appendix A on page 117 for the Summary of the Final

Assessment of Exotic Plant Species of Concern).

Management Zones:

Three management zones are defined for all park management actives: natural,

historic, and developed (RMNP Final Master Plan, 1976). Priorities for controlling

exotic plants are consistent with priorities established for each of these zones.

Natural Zone: This zone includes undeveloped areas of the park. Most of this

area, (248,464 acres or 93% of the park) has been recommended as wilderness.

An additional 2,917 acres is designated as part of the established Indian Peaks

Wilderness. Within this zone, emphasis is on protection of natural resources and

ecological processes. This zone has the highest priority for controlling invasive

exotic plants. Access points (such as trailheads) and trails leading into

wilderness become conduits for seed dispersal, and will be given high priority

for control efforts.

Within the natural zone, there are three Research Natural Areas (RNA’s):

Specimen Mountain, West Creek, and Paradise Park totaling 24,000 acres.

Presently there are no known invasive exotic plants in these RNA’s. Invasive

exotic plants found here will be given the highest priority for eradication.

Historic Zone. This zone includes the William Allen White Zone (5 structures

on less than 3 acres), McGraw Ranch (11 structures on 10 acres), and the

Holzwarth Historic District (12 structures on 75 acres). Invasive exotic plants
23

will be given high priority for eradication if their presence alters the integrity of

an historic landscape. With the exception of invasive exotic plants, exotic

plants that are an integral part of a cultural landscape within these historic zones

will be managed and protected.

Developed Zone. This zone includes 768 acres of park land where

development and intensive use substantially alter the natural environment.

Established uses within the developed zone include campgrounds, park housing,

visitor centers, utility areas, trailheads, and liveries. This zone is managed for

administrative and recreation purposes and is frequently disturbed with

construction and maintenance activities. The Developed Zone has the highest

incidences of invasive exotics.

The developed zone provides an avenue for invasive exotic plants to expand

into surrounding natural areas. Therefore, the developed zone will be given

high priority for exotic plant management to prevent the spread of invasive

exotic plants to undisturbed areas of the park.

In addition to the strategies of the Risk Assessment and Management Zones, other

considerations are examined when establishing priorities for invasive exotic plant

management:

• How does the plant affect the biodiversity of the park?

Areas with significant native plant diversity often contain more invasive exotic

species than areas that have less biodiversity. Consequently, areas with significant

biodiversity are most susceptible to exotic plant infestation (Chong, 2002, Stohlgren

et.al, 1997a,b,c,1999, Kalkan et.al., 2000). These areas, occurring predominantly in

riparian, aspen, ponderosa pine, upland shrub, and dry grassland communities

below 8500 feet, will be given high priority for control. For example, aspen

communities have the highest native plant diversity in the park, but also are at the

greatest risk of losing native biodiversity because of invasive exotic plants (Chong,

2002).

• Is the area susceptible to infestation?

There is evidence to suggest that the structure and site conditions of plant

communities have a significant influence on the capability of exotics to invade and

establish colonies. As stated by McLendon 1996, Kalkan 2000 and Chong 2002,

significant factors include:

- habitat type

- aspect

- moisture

- canopy coverage

- soil

- geology

- competition

- plant diversity
24

• What are the state and county priorities for weed control?

There is a regional list of 90 exotic species considered invasive, which occur in at least one

or more of the following states: Colorado, Wyoming, Utah, New Mexico, Nevada,

Washington, Oregon, Kansas, South and North Dakota, and Montana. These states are

working together to prevent invasive exotic plant infestations. These 90 invasive exotic

plants should be controlled or eradicated if they appear in the park. In addition, Old (1993)

developed a list of 60 plant species that are of concern within the state of Colorado (see

Appendix J on page 143). Many of these species do not yet occur in the state. If these

listed species show up in RMNP, high priority will be given to eradicate them.

• Is an invasive exotic plant within 1/2 mile of the park boundary and threatening

to spread to adjacent lands?

Invasive exotic plants that have the potential to spread to adjacent private or public land

will be given a high priority for control.

• Is the invasive exotic species new to the park or a new infestation of an existing

species?

Exotic plants are much easier to control and less costly to eradicate when they are few in

number. A high priority will be given to eradicating newly discovered infestations of

invasive exotic plants.

In summary, high priority for control will be given to exotic plants that:

• Affect the biodiversity of park resources.

• Threaten rare plant species in the park.

• Occur within the natural zone or RNA’s in the park.

• Occur in developed areas that are “hot spots” or pathways for infestations to spread.

• Threaten the integrity of an historic landscape.

• Are listed by the state and/or county as high priority for eradication or control.

• Occur within 1/2 mile of the park boundary and pose a threat to spread to

neighboring lands.

• Are new infestations of new exotic plant species, having never occurred in the park

before.

• Occur in areas where seed can be rapidly dispersed to other areas of the park.

• Occur at or above treeline (11,500 feet).

• Have an ecological impact greater than 24 in Rutledge & McLendon’s Risk

Assessment.

ACTION 3 ñ Identify control techniques that are most appropriate

for each species.

Control techniques will be selected that achieve maximum effectiveness in eradication

while minimizing risks to natural resources, cultural resources, and the human

environment. They will be identified as appropriate for invasive exotic plant control if

they possess the following characteristics:
25

Control Technique Characteristics:

• The control technique must be effective at killing the invasive exotic plant.

• The control technique poses little or no risk to native vegetation, wetlands, wildlife,

or other natural resources.

• The control technique poses little or no risk to cultural resources.

• The control technique poses little or no risk to the human environment or to the

safety of park visitors or park employees.

• The control technique must be cost-effective to implement.

These characteristics are described in further detail:

• Effective at killing the exotic plant

Five options are available to managers in controlling invasive exotic plants:

Mechanical - Using tools to remove exotic plants by digging, mowing, or cutting.

Cultural - providing competition, stress, or control of exotic species by planting

native vegetation or using prescribed fire.

Chemical - Using synthetic herbicides to kill or severely stress invasive exotic

plants.

Lower-risk methods – Using hot water to scald a plant or the use of natural

herbicides that contain biodegradable soap, acetic acid, sugar compounds, or plant

proteins in place of synthetic herbicides. However, some natural chemicals have

health and safety risks, such as a low pH, that could be caustic to an applicator

applying the chemical. Even these low risk products must be handled in a manner

similar to synthetic chemicals and with appropriate personal protective equipment

(PPE).

Biological - Using insects, mammals, or pathogens to stress exotic plants.

The process of evaluating which technique(s) is/are most appropriate for each

species is known as Integrated Pest Management (IPM).

Techniques vary in effectiveness. In some cases, a combination of treatments is

necessary to meet control or eradication goals. For example, Canada thistle is most

effectively controlled when mechanical means (i.e., mowing) are followed by a

chemical application (Laurie Dieter and George Beck, personnel communication).

Leafy spurge may be most effectively treated with the herbicide Plateau in

combination with a biocontrol, such as insects, or in combination with prescribed

fire.

In all cases, the effectiveness of mechanical, cultural, biological, and low-risk

methods will be evaluated before synthetic herbicide control is proposed. For

example, RMNP initiated research on Canada thistle in 1993 to determine the

factors controlling its distribution in the montane zone (McLendon, 1996).

Recommendations from the research enabled the park to significantly reduce the

amount of herbicides used to control this plant. Wolf (2000) provided

recommendations on controlling white and yellow sweetclover, and determined that
26

herbicides are not necessary in controlling these two species because prescribed fire

is effective at killing the plants. A prescribed fire to control yellow sweetclover

along Trail Ridge Road shoulders from the Beaver Meadows Entrance to Deer

Ridge Junction is being planned in 2003. Future burn plans will be developed for

other areas within treatment areas where prescribed fire has been identified as one

of the control techniques. New research that will start in 2003 will determine if

biological control insects identified to control yellow toadflax could negatively

impact closely related native wildflowers.

• The control technique poses little or no risk to native vegetation, wetlands,

wildlife, soils, or other natural resources.

RMNP will continue to make a good faith effort to evaluate treatment options and

ensure all environmental compliance standards are met. RMNP will review any

new relevant scientific literature and references to ensure the control technique

selected is biologically sound. Some recent research and monitoring pertinent to

RMNP that addresses protecting natural resources:

- Recent research and monitoring using lower risk methods such as hot water and

synthetic herbicides on several perennial plants have not been encouraging

(George Beck and Carlie Ronca, personal communication). The methods appear

to be effective on annuals and perhaps a few biennials, but most of RMNP’s

invasive species of concern are perennial with extensive rhizominous roots.

After treatment with a lower risk technique these species quickly rebounded and

continued to spread and set seed. Susan Wolf (personal communication) stated

that Canada thistle is especially sensitive to corn and wheat gluten meal and this

option will be further explored.

- Presently a research project is ongoing in RMNP that is evaluating ecosystem

impacts resulting from the use of synthetic herbicides. The research will be

completed in 2004 (Moore, 2001). Early data indicates that sites not treated with

an herbicide support higher densities of soil arthropods than treated sites. Data

from this research will be used to minimize impacts to natural resources from

using synthetic herbicides.

- Recent research by Dr. Jorge Vivanco of Colorado State University isolated a

herbicidal chemical called catechin minus. Catechin minus attacks the root cap

and then moves into the root hairs. Lab tests show that it acts quickly, killing

cells and moving from the bottom to the top of plants. Susceptible species

include Dalmatian toadflax and diffuse knapweed. While the preliminary

findings must be verified through additional research, they suggest that a new

type of natural broadleaf herbicide may be available in the future, with the

advantage of being a chemical naturally produced by some plant species.

- Recent research on the biological control species Urophora cardui (a gall fly)

released on Canada thistle has some promising results. However, other research

indicates the fly also negatively impacts native thistles. For this reason RMNP

will not release this insect, though it is anticipated that this fly will eventually be

found in the park due to releases occurring elsewhere in the state (George Beck

and Savata Louda, personnel communication).
27

• The technique poses little to no risks to humans.

Some IPM techniques have the potential to harm humans. Injuries can occur with

the use of weed whackers, scalding hot water and prescribed fire. Herbicides can

impact human health, particularly for those with Multiple Chemical Sensitivity

(MCS). RMNP would like to use both natural and synthetic herbicides on 15

invasive exotic plants in order to achieve effective control and to keep invasive

exotic plant populations from spreading. RMNP proposes to use synthetic

herbicides only as a last resort if other IPM techniques prove ineffective. The type

of chemicals proposed for use and thresholds for chemical control have been

established for the 15 invasive exotic plants (please refer to Appendix C on page

125). The goal of synthetic herbicide use is to reduce the invasive exotic species

below the defined threshold. Once below the threshold, synthetic herbicides would

not be used and RMNP would use other IPM techniques to control plants. The use

of synthetic chemicals would only be warranted if the threshold is exceeded in the

future.

Some species may require more than one application of herbicide. RMNP’s

preference is to only do one application of a synthetic herbicide in any one year

verses multiple applications, but applications could occur once a year over several

years until an invasive exotic is brought below the established threshold level. To

improve the efficacy of an herbicide, other IPM techniques, such as mowing, may

be used before the chemical is applied (Please see Table 4, below). Once herbicides

have been applied and the invasive exotic plant species has been reduced below the

threshold, it is anticipated that herbicides would not be needed for a period of five

(5) years. Presently two of the 15 species are below the defined threshold level

(Please see Appendix C on page 125 and Table 4, below). It is anticipated that nine

additional species could be brought below the threshold level within two years if

Alternative 2 was implemented, and the remaining four species could be brought

below the threshold level in three to five years. None of the 15 invasive exotic

species identified for synthetic herbicide control will be managed solely by the use

of herbicides.

Despite the proposed use of natural and synthetic herbicides, almost all of RMNP will

remain chemical free. By April 30 of each year, park personnel will identify locations

in the park where herbicide application is warranted. Herbicide treatment will not be

done outside of the identified locations. Based on this information, RMNP will

identify trail segments, trailheads, picnic areas, parking lots and campsites that are

located within or adjacent to the planned treatment areas. Areas treated with a

herbicide will be posted at least two weeks before treatment occurs, and yellow signs

will remain in place for three months afterwards. RMNP will also identify all

campgrounds in the park that will remain chemical free for that year. This information

will be made available to the public via the RMNP website and other print media.
28

Table 4 - Estimated Herbicide Treatment Schedule for 15 Invasive Exotic Plants

Species

Estimated Acres to

be initially treated

Estimated Acres

Year Two

Estimated Acres

Year Three

Canada Thistle – based on 80%

estimated efficacy of the herbicide

~16 acres ~3.2 acres ~0.64 acres

Cheatgrass –based on 100%

estimated efficacy of the herbicide

<1.00 0 0

Common St. Johnswort Eradicated * *

Dalmatian Toadflax – Based on

90% estimated efficacy of the

herbicide

3.50 .35 .04

Diffuse Knapweed – Based on

95% estimated efficacy of the

herbicide

1.65 .08 0

Field Bindweed – Based on 90%

estimated efficacy of the herbicide

4.75 .50 .05

Houndstongue –Based on 95%

estimated efficacy of the herbicide

2.50 .12 0

Leafy Spurge – Based on 95%

estimated efficacy of the herbicide

13.75 .69 .03

Oxeye Daisy – based on 90%

efficacy of the herbicide

1.00 .10 0

Orange Hawkweed * * *

Quack grass – Based on 100%

estimated efficacy of the herbicide

1.00 0 0

Smooth Brome – Based on 100%

estimated efficacy of the herbicide

5.00 0 0

Spotted knapweed – Based on

95% estimated efficacy of the

herbicide

<1.00 .05 0

Sulfur Cinquefoil – Based on

90% estimated efficacy of the

herbicide

1.00 .1 0

Yellow Toadflax – Based on

85% estimated efficacy of the

herbicide

12.75 1.91 .29

Total Acres 65.25 7.1 1.05

* Orange hawkweed and Common St. Johnswort are currently below the threshold level that would

warrant chemical control.

• The technique poses little or no risk to cultural resources.

RMNP will identify a control technique that poses minimal or no impact to known

cultural resources. Ground disturbing activities, such as digging plants or use of

prescribed fire, would not be appropriate for exotic plant removal where cultural

resources are present.

• The technique is cost effective to implement.

Cost is not the driving factor in selecting appropriate control techniques for exotic

plant control, but would be considered. For example, based on 2002 figures, exotic

plant control using all IPM techniques except natural and synthetic herbicides
29

required approximately 21 hours per acre at a cost of approximately $268 per acre.

Revegetation cost was $11,000 per acre.

Under some circumstances, the cost of mechanical treatments can be significantly

higher. For example, at Golden Gate National Recreation Area, $80,000 was spent

over five months to control invasive exotic plants on 89 acres (about $900 per acre)

(Bruce Badzik, personal communication).

Herbicide application by a certified chemical applicator using a tractor equipped

with two ten foot booms requires about 1⁄2 hour per acre. Based on 1999 figures

(the last year that herbicides were used in RMNP) the use of herbicides in the park

costs approximately $500 per acre. Using backpack sprayers would take a

significantly longer time and may be more expensive per acre.

In 1999, RMNP spent over $17,000 on invasive exotic plant management such as

mechanical and cultural controls, mapping, and administrative work. Only $3,000

was spent on herbicide application. For every $1 spent on chemical control, about

$6 was expended on mechanical and cultural control. When large infestations are

treated with herbicides, the initial treatment usually results in greater reduction in

the number of plants than can be accomplished with other methods of control.

ACTION 4 ñ Apply the most appropriate control technique.

RMNP recommends specific actions for each of the 35 invasive exotic plants (See

Appendix B on page 120). If it is determined that eradication is not feasible, the

objective will be to suppress the exotic plant population below the threshold level, or

conduct limited eradication or containment in sensitive areas of the park (NPS, 1991

and 2001). In the case of leafy spurge, the action level is reached when only one plant

is found and an herbicide may be used. In the case of bouncing bet, the action level is

reached when one plant is found, yet one plant does not warrant herbicide use since a

single plant can be controlled by hand pulling or digging. 

ACTION 5 ñ Monitor effectiveness of control efforts.

Monitoring is an essential strategy in evaluating control techniques. RMNP will

continue to monitor the occurrence of invasive exotic plants and update the information

annually.

RMNP will continue to monitor areas where invasive exotic plants are removed

(Resources Management Division annual report, 2002). Temporary survey plots are

already in place (please refer to the description of ongoing surveying and monitoring

efforts on page 20), and new survey plots will be established in the future at selected

locations. These survey plots will be used for intensive sampling of vegetative cover

and density.
30

ACTION 6 ñ Prevent new infestations by monitoring exotic plant

pathways.

Exotic plants establish themselves in developed areas and in biologically diverse

habitats. The most heavily invaded sites in the park tend to have a small total area, but

unique plant species (Kalkan 2000, Stohlgren 1999, Chong 2002). These “hot spots” of

infestation provide avenues for invasive exotic plants to expand into other areas of the

park. RMNP will closely monitor these areas, including road shoulders, campgrounds,

trailheads, trails, and diverse habitats such as ponderosa pine, aspen and riparian areas

below 9,000 feet elevation.

To prevent new infestations, RMNP will employ “Best Management Practices,”

including:

• Using only barren fill and gravel in all park construction and maintenance activities.

• To the extent possible, construction and fire fighting equipment will be cleaned

prior to entering the park to prevent the introduction of invasive exotic plant seeds.

• RMNP requires NPS stock and all liveries offering horseback rides into the park to

feed their stock certified weed seed free hay. Private horse users are encouraged to

feed their stock certified hay. Hay certified or not, is not allowed into the

backcountry.

ACTION 7 ñ Inform the Public about exotic plants and control

measures.

RMNP will increase efforts to inform the public about invasive exotic plants and

control measures. A communication plan was developed (please see Appendix F on

page 135). The communication plan is designed to:

• Inform the public about local, regional, and national issues regarding invasive

exotic plants;

• Inform the public about invasive exotic plant control measures in RMNP, especially

herbicide use;

• Inform individuals with Multiple Chemical Sensitivity (MCS) about upcoming

invasive exotic plant control activities within the park that involve the use of

chemicals; and,

• Encourage two-way communication between NPS and the public on matters

regarding invasive exotic plant management in RMNP.

• Areas treated with a herbicide may be closed to the public for a period of time and

yellow signs will be posted.

RMNP will use the following methods to inform the public about invasive exotic plant

management activities:
31

Programs to Inform the Public

• Visitor Centers – Information on invasive exotic plants will be available at visitor

centers through site bulletins, postings on bulletin boards, or through personal

communication by rangers.

• RMNP Information Office – If a chemical, whether it is natural or synthetic, is

proposed for use, the information on chemical application schedules, type of

chemical and location will be available through this office by April 30 each year.

The Information Office will also be notified when a prescribed fire is implemented

to control invasive exotic plants.

• RMNP District Rangers – Information on chemical application schedules, type of

chemical and location will be available to District Rangers by April 30 each year.

• Interpretive Programs – Interpretive talks and guided walks will be designed to

communicate invasive exotic plant management concerns and controls in RMNP.

• Environmental Outreach Programs ñ RMNP will integrate invasive exotic plant

management issues into current environmental education curriculum.

• Press releases – The park will notify local media about exotic plant control

activities, dates, locations and treatment methods.

• Park Newspaper – The park newspaper will contain articles and updates about

invasive exotic species management in RMNP.

• Mail ñ Specific information on chemical treatment locations, dates and treatment

methods will be mailed to park inholders and adjacent landowners within 1⁄4 mile of

a treatment site on, or about, April 30 each year. The park will also develop a

mailing list of other stakeholders who would like to be kept informed about exotic

plant management activities at RMNP.

• Internet ñ Updated information about invasive exotic plant control locations,

scheduled treatment dates, and treatment methods will be posted on RMNP’s web

page.

• Signs – If chemicals are used, the treatment areas will be posted with conspicuous

yellow signs. The signs would state the date of application and the chemical used.

Signs would be posted two weeks prior to the chemical application date, and would

remain in place three months following application.

• Yearly Update – Provide an opportunity for interested individuals to meet and

discuss the effectiveness of all management tools and interchange of new

techniques.

ACTION 8 ñ Work closely with adjacent landowners to achieve

common goals of exotic plant management.

The spread of invasive exotic plants throughout Colorado, the American west, and the

nation poses a serious environmental and economic threat to public land, ranchland,

farmland and private property. RMNP has joined with other federal, state and local

government agencies, homeowner associations, private landowners, and businesses to

develop joint strategies for curbing this silent threat.
32

The park participates in the Colorado Weed Network – an informal network of federal,

state, county, and city officials, and private citizens concerned about exotic plant

infestations. Quarterly meetings provide opportunities to develop regional and local

strategies and coordinate invasive exotic plant control efforts.

The Estes Valley Improvement Association (EVIA), a non-profit civic group, hosts

many public meetings and weed pulling days to promote awareness of invasive exotic

plants.

RMNP will continue to work with volunteers (local and others) in controlling invasive

exotic plants by mechanical, cultural, or biological means. Volunteers have helped to

reduce the number of acres infested with invasive exotics and to contain some problem

plants to specific areas. Almost 800 hours of volunteer time was devoted to controlling

invasive exotic plants in 2002.

RMNP will continue to exchange information with surrounding landowners in an effort

to eradicate or reduce exotic plant populations along shared boundaries. Information is

shared with the U.S. Forest Service, Bureau of Land Management, Bureau of

Reclamation, United States Geological Survey (USGS), Colorado Department of

Agriculture, Colorado Noxious Weed Management Team, County Weed Districts,

Boulder County Open Space, and the towns of Estes Park and Grand Lake.
33

CHAPTER 3 ALTERNATIVES

This chapter describes the alternatives being considered to manage invasive exotic

plants in RMNP. Criteria used in the selection of reasonable alternatives include:

• Potential for protecting the park’s natural and cultural resources

• Effectiveness at eradicating or controlling exotic plant infestations

• Ability to ensure human safety

In addition to a No Action alternative, two alternatives were identified for detailed

analysis. Both action alternatives involve the use of IPM techniques to eradicate and/or

reduce exotic plant infestations in RMNP. The only difference between the two action

alternatives is that one alternative does not include the use of synthetic herbicides. The

No Action alternative provides a baseline against which the environmental effects of

the other two alternatives can be compared.

Alternative 1 ñ Continuation of Current Management Practices:

mechanical, cultural, low risk methods including natural

biodegradable herbicides and biological control (no synthetic

herbicide control).

RMNP is currently using these techniques to control invasive exotic plant infestations

within the park. These activities are Categorically Excluded from compliance with the

National Environmental Policy Act (NEPA). The categorical exclusions read as

follows:

“Routine maintenance and repairs to non-historic structures, facilities, utilities,

grounds and trails” (NPS Director’s Order #12, §3.4.C(3)); and,

“Removal of individual members of a non-threatened/endangered species or

populations of pests and exotic plants that pose an imminent danger to visitors or

an immediate threat to park resources.” (NPS Director’s Order #12, §3.4.E(3)).

If this alternative is selected, RMNP would continue to conduct invasive exotic plant

control work within the park as it has for the past three years, without the use of

synthetic herbicides.

Alternative 2 ñ Preferred Alternative: mechanical, cultural, low risk

methods including natural herbicides, biological and synthetic

herbicide control.

The preferred alternative is based on IPM recommendations for selected species, as

outlined in the following documents:

• “An Assessment of Exotic Plant Species of Rocky Mountain National Park” (1996)

• The Nature Conservancy Weed Control Handbook (2001)

• Recommendations from a variety of experts, and other documents cited in this plan

and EA.

RMNP proposes to implement the full range of IPM techniques. The park would use

mechanical, cultural, low risk methods, biological, and natural and synthetic chemicals
34

to eradicate or reduce the numbers of 35 invasive exotic plants occurring in RMNP. Of

the 35 invasive exotic species identified for control, herbicides will likely be used on

only 15 of those species. Using the full range of IPM techniques would prevent

unacceptable levels of invasive exotic plants using the most economical means while

posing the least hazard to people, property, and the environment.

Alternatives Excluded From Further Consideration

Alternative 3 - No invasive exotic plant management or control.

This alternative was excluded from further consideration because it does not meet the

requirements of the park’s enabling legislation to protect natural resources, the NPS

Organic Act, NPS policies, or the Federal and State Noxious Weed Acts. Although this

alternative was considered, and is used for comparison with other alternatives, it is

unacceptable.

Environmentally Preferred Alternative

The environmentally preferred alternative is determined by applying criteria suggested

in the National Environmental Policy Act of 1969 (NEPA), with additional guidance

provided by the Council of Environmental Quality (CEQ). The environmentally

preferred alternative is the one “that causes the least damage to the biological and

physical environment; it also means the alternative which best protects, preserves, and

enhances historic, cultural and natural resources.” As expressed in section 101 of

NEPA, “it is the continuing responsibility of the Federal Government to:

• Fulfill the responsibility of each generation as trustee of the environment for

succeeding generations;

• Assure for all generations safe, healthful, productive, and esthetically and culturally

pleasing surroundings;

• Attain the widest range of beneficial uses of the environment without degradation,

risk of health or safety, or other undesirable and unintended consequences;

• Preserve important historic, cultural and natural aspects of our national heritage and

maintain, wherever possible, an environment that supports diversity and variety of

individual choice;

• Achieve a balance between population and resource use that will permit high

standards of living and a wide sharing of life’s amenities; and

• Enhance the quality of renewable natural resources and approach the maximum

attainable recycling of depletable resources.”

The environmentally preferred alternative for managing invasive exotic plants in

RMNP is based on these national environmental policy goals. A discussion of how

each alternative relates to these goals follows:

Alternative 1 – Continuation of Current Management Practices. This alternative seeks

to meet the environmental policy goals by using several IPM techniques to eradicate or

control invasive exotic plants. Only natural biodegradable herbicides, usually used by

organic farmers, would be used. Without the use of synthetic herbicides, certain

invasive exotic plant species are likely to spread within the park. Some environmental
35

degradation would occur, which fails to meet one of the environmental policy goals.

For example, in 1999 (the last year a synthetic herbicide was used in the park) leafy

spurge infested about five acres. In 2002, after survey work was completed, it was

determined that leafy spurge now infests 13.75 acres - a 175% increase in just two

years, despite using mechanical and biocontrol techniques to manage this invasive

species.

Alternative 2 – Preferred Alternative. This alternative seeks to meet the environmental

policy goals by eradicating or controlling invasive exotic plants by using the full range

of IPM techniques, including the use of synthetic herbicides. Control techniques would

be tailored to the specific environment in which the invasive plants are found. This

alternative proposes the use of the least toxic effective synthetic herbicide to control

certain species of invasive exotic plants that have exceeded defined thresholds and are

difficult to eradicate or control using mechanical, cultural, biological or other low-risk

methods. To fully meet the environmental policy goals, synthetic herbicides would

have to be used “without degradation, risk of health or safety, or other undesirable and

unintended consequences.”

Summary

Table 5 provides a summary of the potential effects of the No Action alternative as

compared to the potential effects of Alternatives 1 and 2. Chapter 4 provides a

description of the affected environment, and Chapter 5 provides additional information

on the potential impact of the two action alternatives on each resource.

Table 5 Comparative Summary of Environmental Impacts

Impact

Topic

Alternative 1 ñ

Continue Current

Management Practices:

mechanical, cultural, low

risk methods including

natural biodegradable

herbicides, biological

control (No synthetic

herbicide control)

Alternative 2 ñ Preferred

Alternative: mechanical,

cultural, low risk methods

including natural

chemicals, biological and

synthetic herbicide control

Alternative 3 ñ No

Action: no

invasive exotic

plant management or control

Soils and

Native

Vegetation

Long-term beneficial

effects to soil and

vegetation would occur.

There is a risk that some

invasive exotic plants

could expand into

undisturbed habitat with a

long-term minor to

moderate adverse impact

to soil and native plants.

Greatest long-term beneficial

effect on soil and vegetation.

This alternative poses the

least long-term threat to

native species due to exotic

plant invasion. There would

be some short-term localized

minor impacts when natural

or synthetic chemicals are

applied, but native plants are

expected to recover in the

long-term.

This alternative was

considered but

rejected for further

consider-ation due

to expected longterm major impacts

to soil and native

vegetation caused

by the spread of

noxious weeds.
36

Impact

Topic

Alternative 1 ñ

Continue Current

Management Practices:

mechanical, cultural, low

risk methods including

natural biodegradable

herbicides, biological

control (No synthetic

herbicide control)

Alternative 2 ñ Preferred

Alternative: mechanical,

cultural, low risk methods

including natural

chemicals, biological and

synthetic herbicide control

Alternative 3 ñ No

Action: no

invasive exotic

plant management or control

Natural

Soundscape

and

Lightscape

There may be a slight

increase in activities that

may cause excessive or

unnecessary unnatural

sounds. Activities

generating noise would

include using gasolinepowered string trimmers

or mowers, trucks, ATVs,

or the presence of a large

group of volunteers and/or

park employees. There

would be no light impacts.

Effects on natural quiet and

sound would be the same as

Alternative 1.

There would be no

impact because no

weed management

activities would

occur.

Aquatic,

Wetland and

Riparian

Communities

Effects on wetlands and

riparian communities

would generally be

beneficial.

The type of synthetic

herbicides proposed for use,

especially with implementation of the proposed

mitigating measures, would

minimize impacts in the

short-term. The greatest

long-term beneficial effects

to aquatic, wetlands and

riparian communities would

occur.

Without control,

noxious weeds

would spread,

resulting in longterm major impacts

to wetland and

riparian

communities.

Endangered,

Threatened

and Rare

Species

Effects to threatened or

endangered and rare

species would generally be

beneficial. The specieslevel biological diversity of

the park would be partially

protected but not to the

degree afforded by

Alternative 2. The specieslevel biological diversity of

the park may be slightly

jeopardized in the longterm under this alternative.

Alternative 2 would provide

more long-term protection

than Alternative 1 to

threatened, endangered,

candidate species, and rare

species. The species-level

biological diversity of the

park would be better protected

under this alternative in the

long-term when compared to

Alternative 1.

Without control,

noxious weeds

would spread,

resulting in longterm major impacts

to the biological

diversity of the park

and endangered,

threatened and rare

species.
37

Impact

Topic

Alternative 1 ñ

Continue Current

Management Practices:

mechanical, cultural, low

risk methods including

natural biodegradable

herbicides, biological

control (No synthetic

herbicide control)

Alternative 2 ñ Preferred

Alternative: mechanical,

cultural, low risk methods

including natural

chemicals, biological and

synthetic herbicide control

Alternative 3 ñ No

Action: no

invasive exotic

plant management or control

Park Wildlife The integrity of existing

native species would be

enhanced. Some

individual wildlife may be

displaced from their

habitat at certain times,

but would be expected to

return to the immediate

area after perceived

threats are no longer

present. Overall, adverse

impacts would be

localized, short-term, and

negligible to minor in

intensity.

This alternative would have

the greatest beneficial effect.

The integrity of existing

native species would be

enhanced. As in Alternative

1, wildlife would be

frightened or displaced at

times when invasive exotics

are being controlled. There

will be some short-term

impacts to herbaceous plants

from using synthetic

herbicides that will have a

localized effect on forage

available for some wildlife.

With the removal of invasive

exotic plants these areas are

expected to recover. Overall,

the impacts of this alternative

on wildlife would be

adverse, short-term,

localized, and of minor

intensity.

Without control,

noxious weeds

would spread,

resulting in longterm major impacts

to park wildlife.

Wilderness The integrity of

wilderness and its values

would be enhanced.

This alternative would have

the greatest beneficial impact

to wilderness. The integrity

of wilderness would be

enhanced.

Without control,

noxious weeds

would spread,

resulting in longterm impacts to

wilderness.

Air Quality There would be no

significant change in air

quality.

There would be no

significant change in air

quality.

There would be no

impact to this

resource.
38

Impact

Topic

Alternative 1 ñ

Continue Current

Management Practices:

mechanical, cultural, low

risk methods including

natural biodegradable

herbicides, biological

control (No synthetic

herbicide control)

Alternative 2 ñ Preferred

Alternative: mechanical,

cultural, low risk methods

including natural

chemicals, biological and

synthetic herbicide control

Alternative 3 ñ No

Action: no

invasive exotic

plant management or control

Cultural

Resources

Cultural resources would

be protected under this

alternative. Known

archeological sites will be

avoided and will not be

impacted.

This alternative would result

in better protection of

cultural resources in the

long-term. Known

archeological sites will be

avoided and will not be

impacted.

Moderate impacts

would occur to

cultural resources if

invasive exotic

plants are not

controlled.

Human

Environment

A wide spectrum of

visitors would continue to

have multiple means of

access to prime natural,

cultural, scenic and

recreational resources.

There would be localized,

short-term minor impacts

to visitors due to the use

of natural herbicides and

recommended closure of

treated areas for periods of

time. No roads, trails or

campgrounds would be

closed under this

alternative except during

the application of natural

chemicals, such as Burn

Out.

A wide spectrum of visitors

would continue to have

multiple means of access to

prime natural, cultural,

scenic and recreational

resources. Some visitors

would experience short-term

minor impacts due to the use

of synthetic herbicides and

recommended closure of

treated areas for periods of

time. Some visitors, such as

those with Multiple

Chemical Sensitivity, are

likely to avoid the park after

herbicides have been used.

During and after herbicide

application, portions of trails,

parking lots, campgrounds

and trailheads could be

closed for a short period of

time to protect human health.

Closures would negatively

impact some visitors.

Visitor experience

would be

negatively impacted

if invasive exotic

plants displace

native vegetation

and ultimately

wildlife.
39

CHAPTER 4 AFFECTED ENVIRONMENT

Areas of the park that could be affected by exotic plant control are described. Future

site-specific proposals following approval of this plan may require further surveys and

environmental compliance.

Natural Resources

Topography, Geology and Soils

The park features an exceptionally scenic and ecologically typical portion of the

Southern Rocky Mountains. The mountains were formed by a series of granitic

batholiths intruded into precambrian micashists and pegmatities. The geology associated

with the park is generally igneous and metamorphic rock and glacial till.

The Continental Divide bisects the park, dividing it into two distinct drainages. Steep

cliffs and U-shaped valleys characterize the eastern slope. The eastern slope receives

about 15 inches of precipitation annually, and is subject to high Chinook winds

throughout the winter. On the western slope, mountains fall away more gradually to

the Kawuneeche Valley. This side of the Continental Divide receives about 20 inches

of precipitation annually, and typically receives more snow than the eastern slope in

winter.

Nearly one-third of the park lies above treeline (above 11,500 feet in elevation). In the

alpine tundra, precipitation falls as snow for about nine months of the year. Snow can

occur any month of the year.

In 1998, an Order 2 soil survey was completed in the lower elevations of the park and an

Order 3 soil survey was completed for other areas of the park (Natural Resources

Conservation Service 1999). Most soil series in the park are classified in the cryic soil

temperature regime. Data suggest that soils at high elevations and under spruce-fir forest

meet the requirements of the isofrigid soil temperature class. Soil types generally include

Cryochrepts, Cryoboralfs and Cryaquepts. The Cryochrept type is well drained with

moderate permeability and slow runoff. Cryochrepts are generally in the glacial till areas

and are deep to very deep. They may have large stones and boulders on the surface as

well as in the profile. The erosion hazard is slight to moderate. The Cryoboralfs are

moderately well drained with moderate permeability and moderate runoff. The erosion

hazard is slight. The Cryaquepts are poorly to very poorly drained, with slow to moderate

permeability and slow runoff. They are found in the wetter, flatter areas, such as the

Kawuneeche Valley. Erosion is slight unless slopes are denuded of vegetation.

Vegetation

Due to the variation in elevation, climate, and soils, RMNP contains nine distinct

vegetation types. These range from grass/shrub meadows at 7,800 feet to alpine tundra

above 11,500 feet in elevation. Most forested communities are dominated by ponderosa

pine, lodgepole pine, or spruce/fir trees.
40

Approximately 60% of the park is forested, 13% is located above treeline, 18% consists of

exposed rock, and 9% is a mixture of other habitat types (please refer to Table 2 on page

12). Major vegetation types consist of ponderosa pine and grass/shrub habitat between

7,800 ft. to 8,500 ft., lodgepole pine between 8,500 ft. to 9,500 ft, spruce/fir between 9,500

ft. to 11,500 ft., and alpine tundra above 11,500 ft. The west side of the park is

characterized by lodgepole pine and spruce/fir. The Kawuneeche Valley is the largest

riparian meadow in the park and is about nine miles long and 1⁄2 mile wide. The valley is

composed of marshes, bogs, ponds, and wet meadows dominated by sedges and willow.

There are approximately 1,000 known vascular plant species in RMNP. Of these, 115 are

exotic. Thirty-five (35) species of exotic plants are of particular concern due to their

ability to displace native vegetation, and their potential to adversely affect the long-term

health of the ecosystem.

Human activity has altered native vegetation. Prior to the establishment of RMNP in

1915, mining, logging and livestock grazing activities introduced exotic plants into the

area. Building the infrastructure of the park, as well as increasing visitation, has further

contributed to the establishment and spread of exotic plants in RMNP. Developed areas –

including roads, campgrounds, visitor centers, employee housing, utility areas and private

inholdings – contain the largest concentrations of invasive exotic plants and usually occur

in the lower elevations of the park. Some exotic species, however, are spreading to higher

elevations. Three species - yellow toadflax, spotted knapweed and curly dock - were

found along Trail Ridge Road at and above tree line. High altitude was previously

thought to be a natural barrier to invasive exotic plant infestations.

Fire plays a significant role in altering native vegetation and soils. Fire is the major agent

in initiating and terminating forest succession; it controls the age, structure, species

composition and physiognomy of the vegetation; it influences nutrient cycles, energy

flows, productivity, diversity, and stability throughout the ecosystem (Heinselman 1981).

Fire occurs about once every 300 to 700 years in spruce/fire forests, once every 100 to 150

years in lodgepole pine forests, and once every 22 to 308 years in ponderosa pine forests

(Jesse Duhnkrack RMNP, personal communication, and Baker and Ehle, In Press).

At times, fire can be detrimental to native species by favoring the growth of invasive

exotic plants. However, the effect of fire on native vegetation is dependent on the

intensity, and location of a wildland fire. For example, a low intensity wildland fire in

ponderosa pine habitat poses a more serious threat of exotic plant infestation than a high

intensity wildland fire in spruce-fir. This is because ponderosa pine occurs at lower

elevations where invasive exotic plants already have a foothold. For this reason,

ponderosa pine habitat is considered a “hot spot” for invasive exotic species and spruce-fir

habitat is not.

Species such as cheatgrass and spotted knapweed have increased significantly in some

areas of the west following fires (Paige and Ritter 1999, Terry Terrell, personal

communication). On the other hand, some exotic plants such as smooth brome, timothy,

redtop and sweetclovers decrease following a fire (Wolf 2000).
41

Appendix B on page 120 identifies the invasive exotic plants that can be effectively

controlled by the use of prescribed fire. By using Appendix B in conjuction with Figures

1 through 6 and Table 2, areas of the park can be identified where prescribed fire may be

used for exotic plant control. Chapter 5 discusses environmental impacts, including health

and safety concerns, related to prescribed fire and the use of chemicals.

About 63% of the park is designated for Wildland Fire Use. If a fire starts naturally by

lightning in a Wildland Fire Use zone, and if certain parameters are met, a wildland fire

can be managed for resource benefit. These Wildland Fire Use zones are in the more

remote areas of the park and in areas where invasive exotic plants are not expected to

occur.

Natural Soundscape and Lightscape

RMNP contains various tangible natural and cultural features, such as animals, plants,

waters, geologic features, and historic buildings. The park also contains intangible

qualities such as natural quiet, solitude, space, night sky and scenery. Both tangible

and intangible resources are equally important in management decisions affecting park

resources.

About 95% of the park is recommended or designated as Wilderness, where natural

quiet and natural light are considered important resources. RMNP strives to preserve

the natural quiet and the natural sounds associated with the physical and biological

resources of the park.

Aquatic, Wetland and Riparian Communities

RMNP contains the headwaters of four major river basins. These are the Big

Thompson, North Fork of the Colorado, North Fork of the St. Vrain, and the Cache La

Poudre Rivers. The Continental Divide bisects the park into two distinct watersheds.

Water flowing west drains into the Colorado River. Water flowing east empties into

the Missouri and Mississippi Rivers.

RMNP contains 147 lakes and 473 miles of stream. Visitor use and atmospheric

depositions alter water quality. Hiking trails leading to lakes and occurring along

streams are conduits for invasive exotic plants (Benninger 1989, McLendon 1996).

Many high elevation lakes and streams were originally without fish life. Today at least

51 of the lakes sustain trout populations, some due to stocking by settlers or early park

managers. Until 1969, lakes were stocked with exotic trout, which displaced native

trout species. In the late 1970’s park managers stopped stocking exotic trout and began

to reintroduce native trout.

Aquatic/riparian areas contain some of the greatest diversity of habitat for flora and

fauna in the park. These areas are quite sensitive to environmental stresses. High

visitation in these areas increases their susceptibility to exotic plant infestations.

Beaver have influenced streams and lakes in the park. Their populations have

fluctuated over time. Today, the beaver population is considerably smaller than it was
42

150 years ago. This is due to a variety of reasons, some of which are not fully

understood.

There are two Executive Orders (11988 Floodplain Management and 11990 Protection

of Wetlands) that require special consideration on NPS administered land. Whenever

possible, occupancy and modification of floodplains and wetlands are to be avoided.

As a part of this EA, the NPS must determine whether proposed actions may impact

any floodplains or wetlands.

Endangered, Threatened, and Rare Speices

The Endangered Species Act requires the NPS to identify and manage federally listed

threatened or endangered species. As required under NEPA guidelines, a biological

assessment and consultation with the USFWS was done for this plan (Leroy Carlson,

personal communication). On December 30, 2002, RMNP sent a letter to the USFWS

stating that the alternatives being considered for exotic plant control were not likely to

have an adverse affect on endangered, threatened, rare or candidate species. A reply

from the USFWS concurring with the RMNP determination was received on July 10,

2003. Appendix L on page 146 contains both letters. It is well within the spirit of the

Endangered Species Act that RMNP manage state-listed threatened and endangered

species, state special concern species, and any species considered sensitive or rare to

prevent future federal listing.

Appendix D on page 127 is the list of endangered, threatened and rare species for

RMNP. These species are either known to occur in RMNP at this time or have been

observed in the park in the past. Appendix E on page 133 lists the sources used by

RMNP to identify endangered, threatened and rare species that must be protected if

found within a project site.

Wildlife

Rocky Mountain National Park is home to a variety of wildlife species. About 280

species of birds, 66 species of mammals, 11 species of fish, 5 species of amphibians,

and one specie of reptile. The distribution of species within the park varies by season,

elevation, and varieties of habitats present.

Birds in the park include year-round residents, seasonal migrants and breeders, and

occasional visitors. Three life zones (montane, subalpine, and alpine) support a

diversity of avian populations. Common species of birds in RMNP include the

American robin, broad-tailed hummingbird, red-tailed hawk, black-billed magpie,

Stellar’s jay, dark-eyed junco, pine siskin, Lincoln’s sparrow, Wilson’s warbler, greentailed towhee, and mountain chickadee. RMNP was designated a Globally Important

Bird Area in 2000 due to the diversity of birds and breeding habitat for species of high

concern.

Elk, bighorn sheep, moose, and deer are the large ungulates found within the park.

Bighorn sheep are particularly sensitive to human disturbances. The montane life zone

(7,800 to 9,000 feet in elevation) provides the primary winter range for deer and elk.

Moose are found west of the Continental Divide, particularly in the Kawuneeche
43

Valley. Other common mammals in RMNP include the chickaree, coyote, bobcat,

mountain lion, chipmunk, Wyoming ground squirrel, yellow-bellied marmot, and

golden-mantled ground squirrel.

Three exotic bird species, three exotic trout species, and one exotic squirrel specie

reside in the park. Occasionally, a mountain goat or domestic sheep may wander into

the park. When encountered, mountain goats are removed.

Wilderness

Wilderness management programs and policies apply to parks that have designated

wilderness, potential wilderness, and recommended/study wilderness (NPS-41).

RMNP operates under a land classification system that separates the lands within the

park into legally defined zones. These are: recommended wilderness (94% of the total

park area), designated wilderness (1%), administrative (1%), historic (2%), and roads

(2%).

NPS policies state: “The NPS will take no action that would diminish the wilderness

suitability of an area recommended for wilderness study or for wilderness designation

until the legislative process has been completed.” (USDI-NPS Management Policies

Chapter 7:2, 2001, NPS-41). Given this policy, 95% of RMNP is being managed as

wilderness, though only 1% of the park has actually been designated.

Air Quality

The Clean Air Act amendment of 1977 recognizes the need to protect visibility and air

quality in national parks. RMNP is a mandatory Class I area. Visibility is noticeably

impaired in the park 90% of the time. Although pollutants have not been traced to the

source, it is likely that pollutants come from the Front Range of Colorado, and as far away

as Mexico, Texas, and Los Angeles, California. Visitor use has little impact on air quality

in the park.

Research indicates that nitrate levels are increasing at Loch Vale, one of the park’s high

elevation lakes. Atmospheric deposition (acid rain or acid deposition) occurs in the

park, particularly during the summer months. Precipitation measured near park

headquarters and at Loch Vale has an average pH below 5.0 during the summer. This

pH is below natural levels (Keigly and Porter, 1986, Baron, 1991).

In 1993, RMNP exceeded the National Ambient Air Quality Standard (NAAQS) for

ozone. The standard for a 1-hour average is 0.12 ppm (235 μg/m3

). Ozone can be

harmful to people and damaging to some species of plants (Peterson and Arbaugh,

1989). Within RMNP, ozone levels of 0.08 ppm (157 μg/m3

) for a 1-hour average have

been recorded 130 times since 1987. Levels above 0.08 ppm can damage sensitive

plant and animal species
44

Cultural Resources

Historic Resources

There are more than 450 historic structures remaining in the park. Historic resources

relate to mining, ranching, logging, tourist activities, and to facilities associated with

early development of the park. Mining, ranching, logging and many facilities predating

the park’s establishment in 1915 have been removed. Many areas disturbed from the

mid-1800’s to the early 1900’s have been restored to natural conditions.

Historic use of the park resulted in significant impacts to native plants and animals.

Uses that predated the establishment of the park, and even early park activities,

contributed to the introduction of exotic plants.

Prehistoric Resources

Various archeological surveys have identified prehistoric sites and trails. Evidence

suggests that the earliest occupation of what is now RMNP occurred between 10,000

and 15,000 years ago. From at least 9000 years ago and onward there has been

continuous human use of the area (Husted, 1959). Archeological studies have

identified sites and trails that were used by the Ute and Arapaho tribes, including

evidence of historic Ute occupations as late as 1890. Continuous use of the area by the

Arapaho is thought to have occurred from about 1790 to 1860. Pawnee and Sioux may

have camped in the area.

The Ute Trail provided a route across the Continental Divide for both Ute and Arapaho

tribes. Evidence collected from the Ute Trail indicates human use of the area 8,000

years ago.

To date, of the 265,765 acres in the park, about 27,754 acres have been surveyed for

prehistoric or historic archeological sites. Further archeological survey work was

completed during the summers of 1998 - 2002 (Brunswig). More than 800

archeological resources have been recorded in the park’s 88-year history. Few of the

recorded sites have been evaluated for listing in the National Register of Historic

Places.

Human Environment

Socioeconomics

RMNP is one of the most popular tourist attractions in Colorado. The economies of

gateway communities are directly tied to park visitor expenditures. The NPS Money

Generation Model (2002) estimates that RMNP contributes $320 million per year to the

Colorado economy (sales, personal income and value added) and creates 3,800 jobs.

Along the Front Range of the Rocky Mountains is a growing metropolitan area that

extends from Cheyenne, Wyoming, on the north, to Pueblo, Colorado, on the south.

There are over three million people living along the Front Range, all within a relatively

short driving distance to RMNP. The Town of Estes Park is the gateway community on
45

the east side of the park and Grand Lake is the gateway community on the west side.

The full-time population is 11,000 in the Estes Valley. The full time population in

Grand Lake is 320, and about 5,000 people reside in the area that includes the towns of

Grand Lake and Granby.

Visitor Use

People have been recreating in RMNP for more than one hundred years. There were

15,000 visitors during the first year RMNP was open to the public. Since 1994

visitation has exceeded three million visitors per year. Overnight use in the

backcountry has increased since 1984 when 6,536 backcountry permits were issued. In

2002, 7,134 permits were issued, a 9% increase (Barry Sweet, personal

communication).

A yearlong visitor survey was completed in 1994/1995 (Valdez, 1996). The survey

revealed that tranquility, clean air, clean water, and wildlife are extremely important

features for RMNP visitors. Enjoying the natural scenery, wildlife viewing,

photography, scenic driving, and camping were the main activities visitors engaged in

during their visit to RMNP.

Park Operations

The park’s operating budget, Fee Demonstration funds and NPS Natural Resources

Preservation Project funds (NRPP) are currently being used for managing invasive

exotic plants. RMNP retains 80% of funds generated from entrance fees under the Fee

Demonstration Program. In Fiscal Year (FY) 2002 (which ended on September 30,

2002), RMNP spent $42,000 managing invasive exotic plants using mechanical and

biological controls, and $149,200 using cultural controls. Exotic plant management

activities required 3,310 hours of RMNP staff time and 796 hours of volunteer time.

During FY2002 RMNP staff surveyed 292 miles of trails for exotic plants, and treated

or retreated 199 acres (Exotic Plant Management FY2002 Year-end Report).
46

CHAPTER 5 ENVIRONMENTAL CONSEQUENCES

This chapter includes a description of the potential environmental impacts that could

occur to the resources described in Chapter 4 – Affected Environment. Potential

impacts were identified for each of the alternatives based on a review of scientific

literature, resource management plans, field investigations, and the best professional

judgement of resource specialists.

Methodology

This chapter is organized by resource, and is the scientific and analytical basis for the

comparison of alternatives. The consequences of the proposed Integrated Pest

Management (IPM) techniques are evaluated on their effectiveness in eradicating,

suppressing or containing invasive exotic plants while minimizing risks to natural,

cultural resources and the human environment. Impacts are described in terms of

context (effects are site-specific, local or regional), duration (short- or long-term), and

intensity (none, negligible, minor, moderate, major). The thresholds for the intensity of

an impact are defined for each impact topic. Short–term impacts are described as those

that are typically less than several years, such as temporary construction disturbance.

Long-term impacts last many years and often result in long-term changes in land use.

Impacts may be direct, indirect or cumulative:

• Direct effects are caused by an action and occur at the same time and place as the

action.

• Indirect effects are caused by the action and occur later in time or farther removed

from the place.

• Cumulative effects are defined as “the impact on the environment which results

from the incremental impact of the action when added to other past, present, and

reasonably foreseeable future action regardless of what agency (federal or nonfederal) or person undertakes such other actions” (40 CFR 1508.7). Cumulative

impacts can result from individually minor, but collectively significant actions

taking place over time. The Council on Environmental Quality (CEQ) regulations,

which implement the National Environmental Policy Act, require assessment of

cumulative impacts in the decision making process for federal projects. Please refer

to the Cumulative Impacts section for each topic for an analysis of the cumulative

impacts associated with the alternatives.

Past Actions and Reasonably Foreseeable Activities

Cumulative effects were determined by combining the impacts of the proposed

alternatives with potential other past, present, and reasonably foreseeable future actions.

Therefore, it was necessary to identify other ongoing or foreseeable future projects

within RMNP. Reasonably foreseeable future activities are those actions independent

of the Invasive Exotic Plant Management Plan that could result in cumulative effects

when combined with the effects of the proposed control techniques. The cumulative

effect analysis includes all areas within RMNP as appropriate for each resource.
47

Past Actions

Previous impacts in most areas proposed for invasive exotic plant control were due to

the presence of visitors, invasive exotic plants, past and present invasive exotic plant

control, and from earlier anthropic disturbances such as livestock grazing and haying,

water diversions and irrigation, cultivation of grassland meadows, mining, settlements,

lodges, camps and cabins, a downhill ski area, nine hole golf course and park

development activities. The anthropic disturbances varied considerably as to type,

intensity, and duration before and after the park was established. The development of

homes, driveways, roads and trails near the park boundary have also altered the

landscape and has had an indirect impact on the establishment of invasive exotic plants.

Reasonably Foreseeable Activities

The goals of the Invasive Exotic Plant Management Plan are to:

• Eradicate, significantly reduce, or contain populations of 35 invasive exotic plants.

• Prevent further infestations of existing and eradicated species, or new infestations

of invasive exotic species that presently do not exist in the park.

Impairment of Park Resources and Values

In addition to determining the environmental consequences of the preferred and other

alternatives, NPS policy requires analysis of potential effects to determine whether

actions would impair park resources (Management Policies 2001).

The fundamental purpose of the national park system, established by the Organic Act

and reaffirmed by the General Authorities Act, as amended, begins with a mandate to

conserve park resources and values. NPS managers must always seek ways to avoid, or

to minimize to the greatest degree practicable, adverse impacts on park resources and

values. However, the laws do give the NPS the management discretion to allow

impacts to park resources and values when necessary and appropriate to fulfill the

purposes of a park, as long as the impact does not constitute impairment of the affected

resources and values. Although Congress has given the NPS the management

discretion to allow certain impacts within parks, that discretion is limited by the

statutory requirement that the NPS must leave park resources and values unimpaired,

unless a particular law directly and specifically provides otherwise. The prohibited

impairment is an impact that, in the professional judgment of the responsible NPS

manager, would harm the integrity of park resources or values, including the

opportunities that otherwise would be present for the enjoyment of those resources or

values. An impact to any park resource or value may constitute an impairment. An

impact would be more likely to constitute an impairment to the extent that it affects a

resource or value whose conservation is:

• Necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of the park;

• Key to the natural or cultural integrity of the park; or

• Identified as a goal in the park’s general management plan or other relevant NPS

planning documents.
48

Impairment may result from NPS activities in managing the park, visitor activities, or

activities undertaken by concessionaires, contractors, and others operating in the park.

An impairment finding is included in the conclusion section for the following impact

topics: soils and native vegetation; natural soundscape; aquatic, wetland and riparian

communities; endangered, threatened and rare species; wildlife; wilderness; air quality;

cultural resources, and the human environment.

Environmental Consequences

The enabling legislation for RMNP (38 Stat. 798) states that said area is dedicated and set

apart as a public park for the benefit and enjoyment of the people of the United States . . .

with regulations being primarily aimed at the freest use of the said park for recreational

purposes by the public and for the preservation of the natural conditions and scenic

beauties thereof (emphasis added). Therefore, the NPS would like to implement the

alternative that would best control invasive exotic plants and represents the greatest

value for the investment while minimizing the externalities caused by the decision

(water or air pollution is an example of an externality).

Comparison of Alternatives

The types of impacts for each of the alternatives varies because of the various IPM

techniques that would be employed to control invasive exotic plants. The primary

difference between alternatives is that chemical control (the use of synthetic herbicides)

is proposed for Alternative 2. Several documents and many Internet sites were

consulted to provide information on the behavior of synthetic chemicals in the

environment. The documents and web sites are referenced either in the Literature Cited

Section or in Appendix K on page 144. Tables 6 through 9 and Table 11 discuss

synthetic herbicide’s environmental impacts on soils and native vegetation, aquatic,

wetland, and riparian communities, threatened, endangered and rare species, air quality,

and human health effects.

Natural Resources

Soils and Native Vegetation

Methodology and Intensity Thresholds

Determination of the intensity of impacts to soils and native vegetation were derived

from available soils and vegetation information (NRCS and park files) and park staff’s

observation of the effects on soils and vegetation from invasive exotic plants and

control activities. The thresholds of change for the intensity of impacts to soils and

vegetation are defined as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact is at the lowest level of detection and causes very little or

no physical disturbance/removal, compaction, unnatural erosion, when compared

with current conditions.

• Minor ñ The impact is slight, but detectable in some areas, with few perceptible

effects of physical disturbance/removal, compaction or unnatural erosion.

• Moderate ñ The impact is readily apparent in some areas and has measurable

effects of physical disturbance/removal, compaction or unnatural erosion.
49

• Major ñ The impact is readily apparent in several areas and has severe effects of

physical disturbance/removal, compaction, or unnatural erosion.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Soils and Vegetation

Mechanical Control

Mechanical removal of invasive exotic plants is expected to have minor localized

adverse impacts on soil and native vegetation. Some soil erosion and loss of native

plants may occur at the base of an invasive exotic plant if it is dug from the ground. If

a large patch is removed, this could increase soil erosion and have a short-term minor

adverse impact on vegetation.

Recent research on diffuse knapweed indicates that digging a plant from the ground

(i.e. disturbing the soil) could actually enhance diffuse knapweed seed germination and

cause more knapweed seedlings to germinate than if the plant was sprayed with an

herbicide and left in place (George Beck, personal communication). Knapweed seed

remains viable in the ground for years.

For some invasive exotic plants, like Canada thistle, leafy spurge, field bindweed and

yellow toadflax, which reproduce by seed and through rhizomes, hand-pulling large

well established patches is ineffective and can actually promote the spread of the

invasive exotic plant.

In the long-term, native vegetation is expected to recover when invasive exotic plants

are removed (McLendon and Redente 1994). Cutting seed heads and cutting plants at

ground level has no effect on adjacent native species.

Mowing or using a string trimmer causes minor adverse impacts to soil, and would

have a minor adverse impact on native species growing amongst the exotics by cutting

them. When mowed, some invasive exotic species, like diffuse knapweed, still flower

in a dwarfed state and still can produce seed. Timing of mowing is also critical. For

example, mowing before the plant flowers and sets seed can reduce the amount of

viable seed, but mowing after a plant sets seed will scatter seed over a wider area.

Mowing generally does not kill (and may even spread) some invasive exotic plants that

can sprout from rhizomes. However, mowing in combination with another control

technique, such as using a natural or synthetic chemical, can be very effective. Mowing

Canada thistle multiple times in riparian habitat with a high water table can be effective

over three years (George Beck, personal communication).

Mechanical control (such as hand-pulling) is very effective for new infestations of

exotic plants and when plants are few in number. For example, RMNP personnel have

hand-pulled one or two spotted knapweed plants from locations in the park and never

had any recurrence in that area.
50

Cultural Control

Cultural control is expected to have a minor beneficial impact on soil and native

vegetation. Restoring disturbed areas to natural conditions prevents soil erosion and

enhances native plant communities. Maintaining native plant communities in a healthy

vigorous condition can favor native plants over invasive exotic plants (Redente and

McLendon 1994, McLendon 1996).

Prescribed fire can cause a reduction of invasive exotic plants, such as timothy, smooth

brome, and sweetclover, and can stimulate growth of native plants. However, the

ground disturbance caused by fire can also lead to infestations of invasive exotic plants

such as red top, diffuse and spotted knapweed, and yellow and dalmatian toadflax to the

detriment of native plant communities. By using Appendix B in conjunction with

Figures 1 through 6 and Table 2, areas of the park can be identified where prescribed

fire may be used for invasive exotic plant control. Burn Plans developed for prescribed

fires would consider known invasive exotic plant locations. Some areas may be

avoided if prescribed fire would enhance invasive exotic plants. In some locations,

other IPM techniques would be employed prior to a prescribed fire in order to

maximize the efficacy of prescribed fire treatment. Some prescribed fires would be

planned and carried out specifically to control those invasive exotic plants that would

respond favorably to the treatment (i.e. be eradicated or significantly reduced). Fire

effect plots and other study plots would be established before a prescribed fire occurs

and would be monitored afterwards. Increases or decreases in invasive exotic plants

would be noted. General surveys would also be used to detect new infestations after a

prescribed fire or wildland fire. Appropriate control techniques would be implemented

to eradicate or control invasive exotic plants that begin to invade or spread following a

fire. The pros and cons associated with prescribed fire are equal. In other words, the

benefits of removing exotic species by using prescribed fire are offset by the potential

for exotic plants to invade an area following a prescribed fire.

Biological Control

The biological control insects proposed for use in RMNP (see Appendix H on page

141) should have no direct adverse impact on soil or native vegetation, and would

have a minor long-term benefit on soil and native vegetation as exotic plant species

are replace with healthy native plant communities. There is a slight risk that insect

species released in the park may evolve over time and start feeding on native plants

closely related to the invasive exotic species. This could cause a reduction in native

plant diversity and a possible increase in soil erosion. Carefully screening insects, and

long-term monitoring of insects used for biological control, should eliminate these

potential risks to soil and native plants. Some exotic insects being released on invasive

exotic thistles in Colorado are presently impacting native thistles (Louda et al. 1997 and

1998). These insects entered the park from releases done outside the park. RMNP will

work closely with adjacent landowners and will inform them about the risks of using

non-native insects for biological control. RMNP will strive to ensure that exotic insects

with wide diet breath are kept out of the park’s ecosystem.
51

Low Risk Methods

Five low risk methods are considered feasible for use in RMNP. These are:

• Hot water or steam

• Natural products that contain acetic acid

• Sugar compounds

• Covering plants with plastic sheeting

• Natural products that effect plant protein

These low risk methods (excluding plastic) have their limitations and are most effective

on annuals and some biennials. Plastic can be effective, but it kills all plants that are

covered.

Minor localized adverse impacts to native vegetation and soils are expected from hot

water, plastic, or natural chemical treatments. Direct impacts are considered minor

because the hot water, plastic sheeting or natural chemicals would be carefully applied

directly on an invasive exotic plant and used only in selected locations where there are

few native plants. Soil erosion following hot water, plastic or natural chemical

treatments is also considered a minor adverse impact because the area can be

revegetated with native plants if necessary to prevent erosion.

Hot water is applied at a temperature of 230° or 280° Fahrenheit. One of the machines

used to heat and apply the water uses a foam additive composed of 100% plant sugars.

The foam is not toxic or harmful to soil or vegetation. The foam is considered natural

and biodegradable with no negative long-term effects. The heat breaks down the

cellular structure of the plant and immediately starts the decomposition process. It is

effective at killing annuals and can kill or impact some biennial plants for up to eight

weeks. It is anticipated that some deep-rooted invasive exotic plants such as leafy

spurge, yellow toadflax and Canada thistle will not be killed by this method. However,

the technique may still be effective at preventing some deep-rooted species from

flowering and producing seed, especially in sensitive wetland and riparian habitat

where a chemical cannot be used. This method is not selective and can negatively

impact or kill native species. For this reason, hot water control would only be used on

dense patches of invasive exotic plants where there is little risk of impacting native

plant species. This system does not use high water pressure, so soil erosion caused by

application of the heated water is not a concern. However, once the exotic plants have

been eliminated from an area, there is increased potential for soil erosion until native

plants can be reestablished to anchor the soil.

Natural products that contain acetic acid only work effectively in warm weather above

70°F (Bruce Badzik, personal communication). Using a proper surfactant may lower

the necessary temperature for acetic acid to be effective (Tim Gilpin, personal

communication).

Experiments were conducted in 2002 with hot water and sugar. Sugar was applied to

Russian thistle. Results will not be known until 2003/2004. Experiments with hot

water were not very encouraging. Further experiments are needed before hot water as a
52

control technique would be fully implemented. Plastic was used on a dense stand of

Ox-eyed daisy in the late summer of 2002. Results will not be fully known until 2003.

Once the plastic is removed, the area will be reseeded with native species. Plastic is

considered a viable option for controlling dense patches of Canada thistle while plants

are in the rosette stage. It is preferable to use natural chemicals over synthetic if proven

to be an effective technique.

Impacts of Alternative 2 on Soils and Vegetation

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

The use of synthetic herbicide is expected to have a minor localized short-term

adverse impact to native vegetation and soils.

When using synthetic herbicide, three soil characteristics are particularly relevant.

These characteristics are percent organic matter, available water capacity, and soil

permeability. When incorporated into the soil, part of the herbicide dissolves in the soil

moisture and part is adsorbed onto soil particles (primarily organic matter). The

amount of herbicide adsorbed onto soil particles depends on the characteristics of the

chemical and on the amount of organic matter and fine material in the soil. Any

herbicide that remains in water in the soil is available for uptake by plant roots.

However, if the water moves off-site or out of the rooting zone, it takes some of the

dissolved herbicide with it. Depending on the distance of travel, the concentration of

the herbicide, and type of herbicide used, this herbicide movement can be a problem to

susceptible plants (USDA- USFS, 1996). Table 6 presents the behavior of the synthetic

herbicides we propose to use and their effects on soil and plants. Please refer to

Appendix B on page 120 for a list of invasive exotic species we propose to control

using synthetic herbicides. Please refer to Appendix C on page 125 for the threshold

levels that would warrant the use of synthetic herbicides and the type of chemical

proposed to be used. It is anticipated that 65.25 acres of land would be treated with an

synthetic herbicide, which is less than 0.03% of the acreage within the park. If

Alternative 2 is fully implemented, it is anticipated that the amount of land needing

treatment with an synthetic herbicide would be greatly reduced within three years to

about one acre (please see Table 4 on page 28). It is anticipated that after three to five

years, sustainable methods of control such as biocontrol, mechanical, cultural or natural

chemicals would keep plants below established threshold levels. Thereafter, occasional

spot treatments of synthetic herbicides may be required if invasive exotic plants exceed

defined threshold levels.

Soil permeability and water-holding capacity determines how much water moves

through the soil into groundwater or surface water after a rainfall. If the soil retains a

large quantity of water in its upper horizons for later use by plants, the water and

dissolved herbicide will have little opportunity to move. In contrast, if a soil is highly

permeable and has little water-holding capacity, moisture passes through the soil

readily and carries some of the herbicide with it (USDA-USFS 1996). Soil

contamination could be a concern in the short-term. If Alternative 2 is selected, RMNP

anticipates that over the long-term the use of synthetic herbicides would decrease
53

significantly, and there would be times when herbicides would not be used in the park

for a year or more.

RMNP is presently funding a three-year research project to determine ecosystem

impacts resulting from the use of herbicides at the park (Moore 2001). The research

results will be available in 2004. The research is examining four montane plant

communities where herbicides were used in the past and comparing the four sites to

adjacent communities where herbicides have not been applied. Within each site, the

researchers will determine plant community structure, soil characteristics, mycorrhizal

inoculum potential of the soils, the decomposition of the dominant plant litter, and the

soil anthropod community structure (diversity and abundance). Based on the research,

sites treated with synthetic herbicides may be reinnoculated with small amounts of

topsoil from adjacent undisturbed sites to replace mycorrhizal inoculum impacted by

the herbicides, once the invasive exotic plants have been eradicated or suppressed

below established threshold levels.

To reduce the potential for contaminating groundwater with herbicides, an aquifer

vulnerability scoring system – Relative Aquifer Vulnerability Evaluation (RAVE)

developed by the Montana Department of Agriculture was adapted for use at the park

(see Appendix G on page 136). The scoring system takes into account soil texture and

the percent of organic material in the soil. The score card would be used for every

location where a herbicide is proposed to be used. It would indicate which herbicide

should or should not be used, or if the area is not suited for herbicide application.

Table 6 - Behavior of Synthetic Herbicides in Soil and Effects on Target and Nontarget Plants

Herbicide/Active

Ingredient

Behavior of the Herbicide in soil and impact to plants

Redeem R&P

(Triclopyr &

Cloypyralid)

Half-life in soil is on average 30 days but ranges from 10 to 46 days

depending on soil type, moisture, and temperature. It is slightly toxic to

practically nontoxic to soil microorganisms. It is not strongly absorbed in

soil, which varies with soil and clay content, but its major degradate TCP is

expected to be very mobile. Triclopyr is moderately persistent, with

persistence increasing as it reaches deeper soil levels and anaerobic

conditions. Leaching potential is medium. It decomposes by UV light and

the solubility is miscible. It is a growth regulating herbicide for broadleaf

plants. It mimics natural plant hormones. Death usually occurs to the plant

within 3-5 weeks. The herbicide penetrates foliage, with a rain free period of

4 hours and is rapidly transported in plants. Spraying Redeem is not

recommended in loamy sand or sand or where the water table is shallow. If

deemed necessary to treat Canada thistle in these areas, a wick applicator may

be used.

2,4-D Amine or

2,4-D Ester (LVE)

Half-life in soil is 10-days. It rapidly degrades in soil, and is readily taken by

target plants minimizing leaching. It has no effect on microorganisms at

recommended filed application rates. At higher levels, 2,4-D suppresses soil

fungi and nitrogen-fixing algae. Half-life in the soil is 10 days, and has a

medium leaching potential. Average persistency is generally 1-4 weeks in

warm moist soil. It has moved 30-46 cm in sandy soils with heavy amounts

of applied water. Amine is less volatile than Ester formulations. Shows little
54

Herbicide/Active

Ingredient

Behavior of the Herbicide in soil and impact to plants

to no activity on native grasses. If Canada thistle is found in loamy sand or

sandy soil or the water table is close to the surface, 2,4-D Amine or 2,4-D

Ester may be used if the RAVE scoring is favorable, but would only be used

as a last resort.

Transline

(Clopyralid)

The average half-life in soil is one to two months but can range from one

week to one year depending on the soil type, temperature, and rates of

application. Soil microbes degrade it. Where clopyralid leaches to lower soil

depths, it persists longer than it does at the surface because the microbial

populations generally decrease with soil depth. Under aerobic soil

conditions, the half-life is 71 days. No information is available on impacts to

microorganisms. It is weakly absorbed in soil and does not adsorb to soil

particles, with a moderate to high leaching potential. Clopyralid is relatively

persistent in soil, water, and vegetation. Roots and foliage readily absorb the

herbicide. Native grass species are especially tolerant of Transline. It can

easily leach into water and is not recommended in loamy sand or sandy soil

or where the water table is close to the surface.

Roundup & Rodeo

(Glyphosate)

Half-life in soil is as low as 3 days and as long as 141 days. Glyphosate and

the surfactant have no known effect on soil microorganisms. Rapidly and

tightly adsorbed to soil. Low mobility in soils and low potential for run-off.

Is non-selective on plants and will kill all plants it comes in contact with.

Protection of non-target plants is imperative.

Plateau (Imazapic) Average half-life in soil is 120 days. Weakly absorbed in high pH soil, but

adsorption increases with lower pH and increasing clay content. Primarily

degraded by microbes. It has limited mobility, but moderately persistent in

soil. It does not volatilize from the soil surface. The use of Plateau on

invasive exotic plants has restored native plant species. Reseeding can occur

after the herbicide has been applied. This chemical remains in the top 12-18

inches of the soil. Non-target species such as grasses show some browning

after application but no death. There will be no long-term impacts to native

grasses and forbs.

Tordon (Picloram) Average half-life in soil is 90 days, but could be as high as 278 days. Highly

translocated herbicide, active throughout both foliage and roots and many

broadleaf plants. It is persistent and more toxic to some broadleaf plants than

2,4D Amine or Ester, thus precautions must be followed diligently to avoid

injury to non-target plants. It is a restricted herbicide because of potential

injury to susceptible non-target plants. This herbicide has the highest

potential for impacts to non-target species. It is leachable in sandy soil and

not recommended for use in this soil type when the water table is less than 20

feet. The maximum depth of detectable residue was 18 to 24 inches. It is

mobile in water, and leaching is higher with sandy soil or soil with low

organic content. Most grasses are resistant, but most broadleaf plants are

impacted.

Paramount

(Quinclorac)

Half-life in soil is from 18 to 176 days. Slightly absorbed by soil, mobility is

variable depending on soil type. A growth regulator with mainly systemic

action. Adequate soil moisture and/or light rain after application is important

for soil uptake. Thorough coverage is important for consistent weed control.

The organic matter in the soil binds more active material than the clay factor.

Microorganisms degrade the herbicide. Length of residual control can extend
55

Herbicide/Active

Ingredient

Behavior of the Herbicide in soil and impact to plants

for several weeks depending on soil type, moisture regime, etc. The

compound is not volatile and will not influence adjacent plants, but drift onto

desirable broadleaf plants especially in the Linaceae family is a concern and

should be avoided. There is one native species in the park Linum lewisii in

the family Linaceae. The herbicide should be carefully applied if field

bindweed is located with native broadleafs. Application should be by a

backpack sprayer for bindweed patches to minimize drift and consequential

impact to adjacent native plants.

Escort (Metsulfuron

methyl)

The half-life is from 120 to 180 days (in silt loam soil). Insufficient

information is available to determine possible impacts to soil

microorganisms. Generally active in soil, usually absorbed from the soil by

plants. Absorption varies with amount of organic material. Adsorption to

clay is low. Broken down to nontoxic and nonherbicidal products by soil

microorganisms. May injure non-target plants. Application should be

carefully done to protect non-target plants.

Telar

(Chlorsulfuron)

Telar has no effect on soil microorganisms. Half-life in soil is 40 days, but

can range up to 4-6 weeks. Recommended for soils with a pH of 7.5 or less.

It is used at very low rates and is very active. Microbial breakdown is slow.

Moderately mobile at high pH. Leaching is less at pH<6. It has a rapid foliar

and root absorption. It is generally active in the soil and usually absorbed

from the soil by plants. It will leach in sand, sandy loam, silty clay loam, and

silt loam.

Summary of Impacts to Soils and Native Vegetation

Alternative 1 is expected to provide less invasive exotic plant control when compared

with Alternative 2. With the implementation of Alternative 1, some species of invasive

exotic plants would likely be contained if significant resources (time and money) were

devoted to mechanical, cultural, biological and low risk methods of control. There would

be no associated impacts or beneficial effects from synthetic herbicide control.

Hot water, natural chemicals, prescribed fire or plastic could pose a short-term risk to soil

and native vegetation, but native vegetation should return in the long-term. Using hot

water, natural chemicals or plastic only on dense patches of invasive exotic plants would

minimize the risk to native vegetation.

Without the option of using synthetic herbicides, it is expected that some areas would

become “weedier,” negatively impacting native flora and fauna mostly in open meadow,

willow and aspen habitat, which have the highest biological diversity in the park. There

would be long-term moderate negative impacts if synthetic herbicides were not used to

control certain invasive exotic plants. Invasive exotics such as spotted knapweed, yellow

toadflax, Canada thistle, field bindweed and leafy spurge are expected to increase.

Driving motorized vehicles in frontcountry areas when using hot water, or applying an

synthetic herbicides would have a short-term localized minor impact on soils and native

plants.

Implementing Alternative 1 would partially meet the mandate for which the park was

established, which is preservation and protection of natural conditions. This alternative
56

only partially meets the guidelines of the Federal Noxious Weed Act, Executive Order

13112 on Invasive Plants, the Carlson-Foley Act, and the Colorado Undesirable Plant

Management Act.

Alternative 2 would result in the greatest long-term beneficial effects to soil and native

vegetation but would have some localized short-term minor impacts to soil and native

vegetation. Preventing new infestations of invasive exotic plants and reducing or

eliminating current infestations would help restore the vigor of native vegetation. Healthy

native plants benefit the soil by preventing erosion.

The use of synthetic herbicides can pose a short-term risk to native vegetation and soils.

However, the park is committed to using other control techniques first, and would use the

least toxic effective synthetic chemicals only as a last resort. Synthetic chemicals are an

effective means of controlling certain species of invasive exotic plants. The impacts from

using chemicals are short-term, while the benefits to natural resources are long-term.

About 65.25 acres of land have been infested with invasive exotics that have exceeded

defined thresholds and warrant synthetic herbicide control. Without the use of synthetic

herbicides, it is anticipated that the number of infested acres would increase despite the

use of other IPM techniques to control invasive exotics. If Alternative 1 is implemented

instead of Alternative 2, park managers must accept the fact that biological diversity

would be impacted in important habitat mostly below 9,000 feet elevation.

Implementing Alternative 2 would fully meet the mandate for which the park was

established, which is preservation and protection of natural conditions. This alternative

fully meets the guidelines of the Federal Noxious Weed Act, Executive Order 13112 on

invasive Plants, the Carlson-Foley Act, and the Colorado Undesirable Plant Management

Act.

Cumulative Impacts

Previous impacts to soils and native vegetation in most areas proposed for invasive

exotic plant control are due to the presence of invasive exotic plants, past and present

invasive exotic plant control, and from earlier anthropic disturbances such as livestock

grazing and haying, water diversions and irrigation, cultivation of grassland meadows,

mining, settlements, lodges, camps and cabins, a downhill ski area, nine hole golf

course and park development activities. The anthropic disturbances varied

considerably as to type, intensity, and duration before and after the park was

established.

Implementation of Alternative 1 would have a minor cumulative impact on soils and

native vegetation in specific areas of the park primarily due to mechanical control such

as hand pulling and digging, and using natural chemicals. Some impacts could also

occur from motorized vehicles driving in grassland meadows in front country areas if a

method like hot water is used. These cumulative effects would be ameliorated over

time as native vegetation is restored and natural conditions return to previously

disturbed sites. It is anticipated that Alternative 1 may not be effective at controlling

some aggressive invasive exotic plants like spotted knapweed, yellow toadflax, field

bindweed and leafy spurge. If some exotic plant species continue to spread within the

park, it is anticipated that there would be minor to moderate cumulative impacts due
57

to further soil erosion and loss of native plant biodiversity. Disturbances to soil and

native plants would increase as more emphasis is placed on mechanical control.

Alternative 2 would have a minor cumulative impact similar to Alternative 1. It is

anticipated that troublesome invasive exotics plants would decrease as the full range of

IPM techniques are implemented, and native vegetation would be restored, resulting in

the amelioration of cumulative impacts. Native plant biodiversity is expected to

increase in the long-term.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to soils or native vegetation whose

conservation is: 1) necessary to fulfill specific purposes identified in the enabling

legislation of RMNP; 2) key to the natural or cultural integrity of the Park; or 3)

identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.

Natural Soundscape and Lightscape

Weed management activities will not be conducted at night, so there will be no impacts

to the natural lightscape associated with any of the IPM techniques.

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts were derived from park staff’s

observations of the effects on the natural soundscape from invasive exotic plant control

activities. The thresholds of change for the intensity of impacts to the natural

soundscape are defined as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact is at the lowest level of detection and causes very little or

no physical disturbance when compared with current conditions.

• Minor ñ The impact is slight, but detectable in some areas, with few perceptible

effects of physical disturbance.

• Moderate ñ The impact is readily apparent in some areas and has measurable

effects of physical disturbance.

• Major ñ The impact is readily apparent over a larger area and has severe effects of

physical disturbance.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.
58

Impacts of Alternative 1 on the Natural Soundscape

Mechanical Control

There would be negligible short-term localized noise impacts associated with hand

pulling, digging, or cutting of noxious weeds. There would be minor short-term

localized noise impacts associated with the use of string trimmers or mowers powered

with gasoline engines.

Cultural Control

There would be negligible to minor localized short-term noise impacts associated

with revegetation activities and prescribed fire activities.

Biological Control

There would be no noise impacts associated with biological control.

Low Risk Methods

The hot water machine is noisy and would cause short-term localized minor noise

impacts to park visitors and wildlife within hearing distance of the machine. Because

of the weight of the machine, it has to be placed in the back of a truck or towed in a

trailer behind an All Terrain Vehicle (ATV).

Impacts of Alternative 2 on the Natural Soundscape

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

Backpack sprayers carried by a contractor, park employees, or by horse would be used

to apply herbicides in some locations. There would be negligible short-term localized

noise impacts associated with the use of backpack sprayers. Tractors or ATVs would

be used when applying chemicals in front country meadows. This would result in

short-term localized minor noise impacts. There would be no aerial application of

herbicides, so impacts from a helicopter or fixed winged aircraft will not occur.

Summary of Impacts to the Natural Soundscape and Lightscape

Alternative 1 would result in short-term localized negligible to minor noise impacts

because of invasive exotic plant management activities. Most noise would be associated

with mechanical control methods such as digging and cutting of plants and the use of a hot

water machine. In limited cases, a gasoline-powered string trimmer or a mower would be

used in the Natural, Historic and Developed Zones. Occasionally string trimmers may be

used in designated or recommended wilderness if determined to be the minimum tool

needed to accomplish the work.

Alternative 2 would result in short-term localized minor noise impacts from the use

of tractors or all-terrain vehicles which would be used when applying synthetic herbicides

in front country meadows. There would be no aerial application of herbicides, so impacts

from a helicopter or fixed winged aircraft will not occur.
59

Cumulative Impacts

Noise impacts in RMNP are most often caused by aircraft overflights, vehicle traffic

and human voices (noisy campers, hikers, etc.). When added to these existing noise

impacts within the park, weed management activities can

result in short-term localized minor cumulative impacts.

The NPS has removed numerous camps, lodges, and other developments from the park,

including a nine-hole golf course and ae ski area. Natural quiet, sounds and light have

been restored to these previously developed sites. However, the NPS has also

developed numerous facilities for park visitors and to facilitate the management of the

park. These facilities include roads, campgrounds, trails, visitor centers, entrance

stations, administrative and maintenance facilities, and housing for park employees.

All of these facilities have impacted natural quiet, sounds and light.

Alternative 1 would create negligible to minor localized cumulative impacts to the

natural soundscape with no cumulative impacts to the lightscape. This impact would

be of short duration and localized to specific areas of the park where mechanical

control (i.e., use of a mower, string trimmer or a hot water machine) was being done.

Use of a hot water machine or mower would be restricted to front country areas, but a

string trimmer could be used in wilderness areas if deemed the necessary minimum

tool. It is anticipated that Alternative 1 may not be effective at controlling some

aggressive invasive exotic plants like spotted knapweed, yellow toadflax, Canada

thistle, field bindweed and leafy spurge. If some exotic plant species continue to spread

within the park, additional mechanical, cultural and low-risk control would be required,

which would create additional cumulative impacts to natural quiet and sounds.

Alternative 2 would create negligible to minor localized cumulative impacts to the

natural soundscape with no cumulative impacts to the lightscape. In addition to the

use of mowers, string trimmers or a hot water machine, noise would also be generated

by spraying equipment and vehicles used to transport the equipment. This impact

would be of short duration and localized to specific areas of the park where control

work was being done. It is anticipated that troublesome invasive exotics plants would

decrease as the full range of IPM techniques are implemented, and native vegetation

would be restored. This would reduce the need for exotic plant control and would

reduce impacts to natural quiet and sounds.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to the natural soundscape and

lightscape whose conservation is: 1) necessary to fulfill specific purposes identified in

the enabling legislation of RMNP; 2) key to the natural or cultural integrity of the Park;

or 3) identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.
60

Aquatic, Wetland and Riparian Communities

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts were derived from research conducted in

the park, park files, scientific literature, and park staff’s observations of the effects on

aquatic, wetland and riparian communities from invasive exotic plants and control

activities. The thresholds of change for the intensity of impacts to aquatic, wetland and

riparian communities are defined as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact is at the lowest level of detection and causes very little or

no physical disturbance when compared with current conditions.

• Minor ñ The impact is slight, but could be detectable in some areas, with few

perceptible effects.

• Moderate ñ The impact is readily apparent in some areas and has measurable

effects.

• Major ñ The impact is readily apparent in several areas and has severe effects.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 to Aquatic, Wetland and Riparian Communities

Mechanical Control

Removing invasive exotic plants by tools is expected to have minor impacts to

aquatic, wetland and riparian communities. Some soil erosion and loss of native

plants may occur at the base of an invasive exotic plant if dug from the ground. If a

large patch is removed from a wetland this could increase soil erosion and have a shortterm impact on riparian communities and water quality, but a long-term benefit is

expected with the restoration of the native plant community.

Native riparian vegetation is expected to recover when invasive exotic plants are

removed over the long-term (Redente and McLendon 1994). Cutting seed heads and

cutting plants at ground level would have no negative effect on adjacent native species.

The removal of invasive exotic plants would enhance native species. Water quality

should remain good or improve in the long-term with the restoration of native

vegetation and protection of soils.

Mowing would not be allowed in riparian communities, but a string trimmer could be

used. Cutting invasive exotic plants would not disturb the soil, but could have a minor

impact on native species growing amongst the exotics. Cutting is not an effective

means of control for many invasive exotic plants that occur in riparian habitat, but

could be effective at preventing some species from flowering and producing seed. The

one exception could be cutting Canada thistle. Repeated mowing or cutting of Canada

thistle over several years could be effective where the root system is restricted by a high

water table, such as near rivers (Beck and Sebastian 2000). Cutting invasive exotic
61

plants generally does not kill (and may even spread) some invasive exotic plants that

reproduce by seed and through rhizomes.

Cultural Control

Restoring disturbed riparian communities to natural conditions by replanting native

plant species will reduce soil erosion, enhance native plant communities, and improve

water quality. Cultural control through native plant restoration will result in a minor

benefit to aquatic, wetland and riparian communities. Maintaining riparian

communities in a healthy vigorous condition favors native plants over invasive exotic

plants (Redente and McLendon 1994, McLendon 1996).

Prescribed fire may be used to maintain healthy native plant communities in sedge,

grass or rush communities in riparian areas, and in willow habitat. Due to the negative

effects of heavy elk browsing in willow and aspen communities, prescribed fire is not

likely to be used for the foreseeable future. The combination of prescribed fire and elk

browsing can negatively impact willow and aspen. Timothy is an invasive exotic plant

that could be managed with prescribed fire in riparian areas. Red top and yellow

toadflax are species that could increase from a prescribed fire in riparian areas. Areas

infested with red top or yellow toadflax should not be burned. Burn units in riparian

communities have to be inventoried, and invasive exotic species documented to

determine whether prescribed fire should be used. Prescribed fire would have a shortterm minor impact on aquatic and wetland communities by increasing sediment.

Prescribed fire would have a long-term benefit when riparian communities are restored.

Biological Control

The use of biological control insects proposed for use in RMNP (see Appendix H on

page 141) should have no impact on aquatic, wetland or riparian communities.

Biological control insects would be carefully chosen to selectively feed on the invasive

exotic plants to be controlled. However, one biological control insect that was released

outside the park has become established within the park. This insect, though

inadvertently introduced to the park, is negatively impacting native thistles in and near

wetland habitat.

Low Risk Methods

There would be minor short-term adverse impacts to aquatic, wetland and riparian

communities associated with the use of low risk methods. Because of concerns related

to the use of synthetic herbicides in or near aquatic, wetland and riparian communities,

low risk methods would be more extensively used. There would be long-term benefits

when invasive exotics are removed and riparian communities are restored to natural

conditions. Hot water, depending on the machine used, is applied at a temperature of

230° or 280° Fahrenheit. One of the machines uses a foam that is composed entirely of

plant sugars. The foam formula would have a negligible short-term impact on

aquatic, wetland and riparian communities. The recommended mix for the foam

formula is .0004 mg/l, which is well below the 10 mg/l at which detrimental effects on

aquatic organisms would occur. Deep rooted invasive exotic plants, such as leafy

spurge, yellow toadflax, and Canada thistle, may not be killed using the hot water

method. Corn or wheat gluten meal may be effective for controlling Canada thistle.
62

Using natural chemicals would not be effective on deep-rooted invasive exotic plants

such as leafy spurge.

Impacts of Alternative 2 to Aquatic, Wetland and Riparian Communities

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

With the implementation of the Mitigation Measures that appear on page 104, the use

of synthetic herbicides near water could result in negligible to minor short-term

adverse impacts to aquatic, wetland and riparian communities. Herbicides have the

potential to enter open water through runoff and spills. Herbicide concentrates are

potential point sources of pollution that can impact surface and groundwater. When the

concentrate is mixed with water and applied to invasive exotic plants, contamination of

surface waters because of runoff is unlikely except when heavy rainfall occurs soon

after application. Applying herbicides when rainfall is imminent would be prohibited

except for Paramount, where adequate soil moisture and/or light rain is important for

soil up take. Leaching, root uptake, and movement in soil and groundwater are the

primary hydrologic processes governing herbicide movement (Neary and Michael

1988).

RMNP adopted the Relative Aquifer Vulnerability Evaluation (RAVE) developed by

the Montana Department of Agriculture and modified for RMNP, to help reduce the

potential of contaminating groundwater with herbicides (see Appendix G on page 136).

The scoring system takes into account depth to groundwater, topographic position,

distance to surface water, annual precipitation, herbicide application frequency,

herbicide application method, and leachability. The score card would be used for every

location where a synthetic herbicide application is proposed. Using this system would

indicate which herbicide should be used or if the area is not suited for herbicide use.

Table 7 presents the behavior of the synthetic herbicides proposed for use in RMNP in

aquatic, wetland and riparian communities. Herbicides proposed for use near water

resources must be approved for use in and around water. Hand application methods,

such as using a wick or wand applicator, may be used. Personnel applying herbicides

would follow all label directions and precautions. Herbicide drift would be negligible

with implementation of mitigation measures including requiring the use of buffer zones

(see Mitigation Measures on page 104). Implementation of mitigation measures

associated with the protection of water quality, and use of the RAVE score card system,

would minimize effects on aquatic, wetland and riparian areas.

The potential impact of herbicides on fish and other aquatic organisms is a function of

two factors: the toxic characteristics of the herbicide and the concentration of the

herbicide to which the fish or other organisms are exposed. Herbicides applied in

accordance with label restrictions are expected to have negligible impacts on fish or

aquatic organisms because concentrations are so dilute. Table 7 provides a summary of

the risks associated with use of the herbicides identified in this plan/EA. This summary

is based on previous risk assessments for herbicide (USDA-USFS 1992).
63

Table 7 - Behavior of Synthetic Herbicides in Aquatic, Wetland, and Riparian

Communities

Herbicide/Active

Ingredient

Behavior of the Herbicide in Aquatic, Wetland and Riparian

Communities

Redeem R&P

(Triclopyr &

Clopyralid)

Leaching potential is medium, half-life in soil is on average 30 days

but ranges from 10 to 46 days depending on soil type, moisture, and

temperature. Spraying Redeem is not recommended where the water

table is shallow. If deemed necessary to treat Canada thistle in these

areas, a wick applicator may be used. Avoid drift into surface water.

Both triclopyr BEE and triclopyr TEA may produce TCP, which is

relatively mobile and persistent and has the potential to degrade

groundwater. Triclopyr and TCP do not absorb to soil and sediment

particles, and may be transported by surface runoff waters. However,

Troclopyr is not predicted to persist in surface waters. The half-life in

river water using natural light sources was 1.7 days.

2,4-D Amine or

2,4-D Ester (LVE)

In surface water, microorganisms readily degrade 2,4-D. Rates of

breakdown increase with increased nutrients, sediment load, and

dissolved organic carbon. Under oxygenated conditions, the half-life

is 1 to several weeks. 2,4-D has only limited potential to contaminate

groundwater. 2,4-D is mobile to highly mobile in sand, silt, loam, clay

loam, and sandy loam soils. However, it is unlikely to be a groundwater contaminant due to the rapid degradation of 2,4-D in most soils

and rapid uptake by plants. 2,4-D residues dissipate rapidly in surface

water, especially in moving water. 2,4-D residues may be detected in

still water after 6 months. Do not apply 2,4-D directly to water or

wetlands such as swamps, bogs, marshes, and potholes except as

specified for certain aquatic uses. Most cases of groundwater

contamination have been associated with mixing/loading and disposal

sites where it is heavily used, but this will not occur in RMNP. 2,4-D

Amine is toxic to aquatic invertebrates. Avoid drift and runoff that

may adversely affect aquatic invertebrates and non-target plants.

Transline

(Clopyralid)

It is highly soluble in water. Because it is highly soluble it does not adsorb to

soil particles and is not readily decomposed in some soils. It may leach into

groundwater. Groundwater may be contaminated if Transline is applied to

areas where soils are very permeable and the water table is shallow. There is

also the potential to contaminate surface waters. Clopyralid is relatively

persistent in soil, water, and vegetation. Warm, moist soils treated at low

rates will lose clopyralid in a comparatively short period, whereas when

applied to cold, dry soils or waterlogged soils, and at higher rates, clopyralid

residues may persist for several years.

Roundup & Rodeo

(Glyphosate)

The Roundup and Rodeo formulations are two of only a few herbicides

approved for controlling weeds in delicate aquatic environments. Strongly

adsorbed to suspended organic and mineral matter, which makes it unlikely to

leach into water. However, glyphosate can move into surface water when

soil particles to which it is bound are washed into streams, rivers or lakes.

Primarily broken down by microorganisms. Half-life in soil is 30 days.
64

Herbicide/Active

Ingredient

Behavior of the Herbicide in Aquatic, Wetland and Riparian

Communities

Plateau (Imazapic) Plateau is soluble in water and is hydrolytically stable in aqueous solution.

Plateau in water is, however, rapidly photo degraded by sunlight with a halflife in water of from less than 8 hours to one to two days. Based on the

chronic reference dose (RfD) of 0.05 mg/kg b.w./day, set by EPA for the

time-limited tolerance and the EPA’s default factors for body weight and

drinking water consumption, the Drinking Water Level of Comparison

(DWLOC) was 1700 ppb and for children the DWLOC was estimated to be

500 ppb. It has little lateral movement in soil. No residues were found below

the 18-24 inch soil layer. Plateau does not readily move off site and binds

moderately to most soil types. Imazapic is not registered for aquatic use.

Tordon (Picloram) Is soluble in water, and may be mobile. Can, under certain conditions,

contaminate groundwater, which may be used for irrigation and drinking

purposes. Under some conditions, Tordon may also have a high potential for

runoff into surface water (primarily via dissolution in runoff water). These

include poorly draining or wet soils with readily visible slopes toward

adjacent surface waters or stream banks that are unstable and may slip into

the stream, sites with a water table within 72 inches (6 feet) of the surface and

course textured soils, areas inside the annual flood plain, frequently flooded

areas, or areas over-laying extremely shallow groundwater. These properties

combined with its persistence, means it may pose a risk to groundwater

contamination. The buffer zone for use of Tordon within RMNP would be

200 feet from any aquatic, wetland or riparian area because of its potential to

contaminate aquatic systems. Tordon will not be used when depth to water is

less than 72 inches. The RAVE score card would determine if Tordon is

appropriate in a particular location.

Paramount

(Quinclorac)

After application there is little potential for movement off of the treated area.

It is not volatile and binds moderately to most soil types once applied. There

are no known instances where Paramount has moved from a treated site into

surface water. It is rather persistent in soil and prone to leach into

groundwater, so Paramount will not be used where the water table is close to

the surface (<60 inches). DWLOCs for chronic dietary exposure in drinking

water, 12,000 micrograms/L for U.S. population in surface water, 2,700

micrograms/L for infants/children.

Escort (Metsulfuron

methyl)

Escort dissolves easily in water. It has the potential to contaminate

groundwater at very low concentrations. It leaches through silt loam and

sandy soils. The half-life is from 120 to 180 days in silt loam soil. Because it

is soluble in water, there is a potential for surface waters to be contaminated if

it is applied directly to bodies of water or wetlands. Tests show that the halflife for Escort in water, when exposed to artificial sunlight ranged from 1 to 8

days.

Telar

(Chlorsulfuron)

Telar may be dispensed as a suspension in water with constant agitation.

Purified chlorsulfuron, which is the active ingredient, is soluble in water. The

potential for leaching is high in permeable soils. However, significant

groundwater contamination should not occur because of the low use rates and

the dispersion of residues with leaching. No information is available for

surface water. For this reason, a buffer zone would be maintained when

applying it near surface water, or hand methods such as a wick applicator

could be used to avoid drift.
65

Summary of Impacts to Aquatic, Wetland and Riparian Communities

Alternative 1 would result in some long-term minor beneficial effects to aquatic,

wetland, and riparian communities. In the long term, this alternative has a higher risk

for failure. Without the limited use of synthetic herbicides, infestations of some exotic

plants would increase in wetland, and riparian communities, negatively impacting these

sensitive resources. Other IPM techniques, such as hot water and using natural

chemicals, would be more extensively used to control persistent plants, which may

reduce the amount of infested acres.

With the implementation of mitigation measures (Please see page 104) and the use of

the RAVE scorecard, Alternative 2 would result in short-term negligible to minor

impacts to aquatic, wetland and riparian communities. The level of impact is

dependent on the herbicide selected and distance to surface and groundwater. Some of

the synthetic herbicides proposed for use in RMNP would not be used near aquatic,

wetland or riparian communities, others would only be used with a wand or wick

applicator.

Selection of the most appropriate chemical is based on current information acquired

and approved through the following sources:

• NPS-Pesticide Use Proposal System (Intermountain Region IPM Specialist)

• Internet sources

• Environmental documents prepared by the Bureau of Land Management (BLM

1991)

• Environmental documents prepared by the U.S. Forest Service (USDA-USFS

1992).

Any pesticide use in RMNP requires review and approval by the regional NPS IPM

Specialist.

This alternative would result in a long-term moderate benefit to aquatic, wetland, and

riparian communities. The implementation of this alternative would ultimately

decrease the use of chemicals and some years the park would be herbicide free.

Cumulative Impacts

Previous impacts to aquatic, wetland and riparian communities in most areas proposed

for invasive exotic plant control are due to continued visitor use, the presence of

invasive exotic plants, past and present invasive exotic plant control, and from earlier

anthropic disturbances such as livestock grazing and haying, water diversions and

irrigation, cultivation of grassland meadows, a nine hole golf course, a downhill ski

area and park development activities. The anthropic disturbances varied considerably

as to type, intensity, and duration before and after the park was established.

Alternative 1 would result in minor cumulative impacts to wetland and riparian

vegetation in specific areas of the park primarily due to mechanical control such as

hand pulling and digging. No motorized vehicles would be allowed in wetland and

riparian communities. It is anticipated that Alternative 1 would not be effective at
66

controlling some aggressive invasive noxious weeds like yellow toadflax and leafy

spurge that occur in or near wetland habitat. Weed cutting and using corn or wheat

gluten meal may be effective in controlling Canada thistle. Plastic sheeting may also be

used on dense patches of some invasive exotics. If some exotic plant species continue

to spread within the park, additional mechanical, cultural and low-risk controls would

be required, which would create additional cumulative impacts to wetland and riparian

vegetation.

Alternative 2 would result in minor cumulative impacts to wetland and riparian

vegetation in specific areas of the park primarily due to mechanical control and

synthetic herbicide control. Using the RAVE scoring system (please refer to Appendix

G on page 136) and implementation of mitigating measures would reduce the potential

for contaminating groundwater and impacting wetland and riparian communities. To

minimize cumulative impacts on wetland and riparian communities, synthetic

chemicals would only be used after other IPM techniques were determined to be

ineffective. If synthetic herbicides are used, wick or wand applicators would be used to

further minimize impacts to wetland or riparian communities. It is anticipated that

troublesome invasive exotics plants would decrease as the full range of IPM techniques

are implemented, and native vegetation would be restored. This would reduce the need

for exotic plant control and would reduce impacts to wetland and riparian areas.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to aquatic, wetland or riparian

communities whose conservation is: 1) necessary to fulfill specific purposes identified

in the enabling legislation of RMNP; 2) key to the natural or cultural integrity of the

Park; or 3) identified as a goal in the Master Plan (1976) or other relevant NPS

planning documents, there would be no impairment of the Park’s resources or values if

either Alternative 1 or 2 is selected.

Endangered, Threatened and Rare Species

Studies demonstrate that invasive exotic plants cause reduced abundance of and/or

diversity of birds, reptiles, small mammals and insects (Huenke 1996). Habitat tends to

degrade from the invasion of exotic plants, which has a direct impact on endangered,

threatened and rare species (Olson 1995). Grass production can drop by as much as

90% with the expansion of invasive exotic plants (Harris and Cranston 1988). This in

turn reduces forage and cover for wildlife. Displacement of native plants by non-native

invaders may be a primary mechanism for global and regional loss of biodiversity

(Stholgen 1999). Containing, controlling, and eradicating the 35 invasive exotic plants

addressed in this Plan would protect endangered, threatened and rare species within the

boundaries of the park. The U.S. Fish and Wildlife Service (FWS) Ecological Services,

Colorado Field Office, was consulted in December 2002 regarding this Plan. RMNP

seeked concurrence for our initial assessment that implementation of the alternatives is

not likely to have an adverse effect on the park’s federally listed, candidate or rare

species. A copy of the letter is in Appendix L on page 146. On July 3, 2003, RMNP

received concurrence from the FWS via a telephone call and received a letter on July
67

10, 2003 concurring with the park’s assessment. A copy of the letter is in Appendix L

on page 147.

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts were derived from available information

on endangered, threatened and rare species. Map locations of sensitive resources were

compared with known invasive exotic plant populations. Predictions about short- and

long-term site impacts were based on existing inventory and monitoring data from

RMNP. The thresholds of change for the intensity of impacts to endangered, threatened

and rare species are defined as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact could result in a change to a population or individuals of a

species or resource but the change would be so small that it would not be of any

measurable or perceptible consequence.

• Minor ñ An action that could result in a change to a population or individuals of a

species or a resource. The change would be small and localized and of little

consequence.

• Moderate ñ An action that would result in some change to a population or

individuals of a species or resource. The change would be measurable and of

consequence to the species or resource but more localized.

• Major ñ An action that would have a noticeable change to a population or

individuals of a species or resource. The change would be measurable and result in

a severely adverse or major beneficial impact, with possible permanent

consequences for the species or resource.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Endangered Threatened and Rare Species

Mechanical Control

Removing invasive exotic plants using tools would have negligible adverse impacts to

federally listed threatened, endangered or rare species. Every area proposed for

invasive exotic control work would be checked before work begins, and work would be

adjusted accordingly to protect these sensitive species. No threatened or endangered

species is known to occur in any area presently proposed for control work, but some

rare plants do occur. There are no known federally listed threatened or endangered

plants within the boundaries of RMNP, but there are some listed wildlife (refer to

Appendix D on page 127).

Removing invasive exotic plants using tools would have negligible adverse impacts to

state listed threatened or endangered species. Surveys documenting rare plants have

been ongoing for a number of years, and all known rare plant locations are being

mapped and entered into the park’s Geographical Information System (GIS) database.
68

Rare plant locations are being assessed for threats by invasive exotic plants (DBG

2000). This information would be made available to crews involved in control efforts.

Some soil erosion and loss of native plants may occur at the base of an invasive exotic

plant if it is dug from the ground. If a large patch is removed, this could increase the

chance that rare plant species could be affected. Flagging would be used to identify

known locations of rare plants when exotic plant control work is to be conducted

nearby. If invasive exotic plants are intermixed with rare plants, control work would be

carefully done by hand pulling or digging.

Native vegetation is expected to recover in areas where invasive exotic plants are

removed (McLendon and Redente 1994). Cutting seed heads and cutting plants at

ground level would have no effect on adjacent native species. With the removal of

invasive exotic plants, the native species will be enhanced.

There could be a short-term displacement of endangered, threatened and rare wildlife

when working in the area. Presently, there are no known patches of invasive exotic

plants near known breeding locations of endangered, threatened or rare wildlife species.

The Northern goshawk (a state vulnerable species) is at the greatest risk for

displacement since its habitat falls within known areas of invasive exotic plants, but

goshawks tend to nest in dense forest that is not conducive to invasive exotic plants.

Goshawks forage in open meadows where invasive exotic plants occur, and the longterm consequences of removing invasive exotic plants would enhance native flora and

consequently native prey.

Gas powered mowers or string trimmers would not be used near endangered, threatened

or rare flora or fauna. Mechanical treatment is labor intensive, but is recommended for

small infestations. Because some areas require periodic mechanical control, impacts

from mechanical treatment can be recurring.

Cultural Control

Restoring disturbed plant communities to natural conditions through revegetation

efforts would provide a long-term benefit to threatened or rare species. Cultural

treatments can benefit native plants and wildlife. Rare plants are managed under a

Class I designation when revegetation is considered as per the Vegetation Restoration

Management Plan for RMNP (McLendon & Redente, 1994). The primary goal of

revegetation efforts is to insure that rare plant communities are protected. Genetic

integrity and local genotypes of rare plants must be preserved. Revegetation near rare

plants would be the minimum necessary to ensure the preservation of the rare species,

and would rely heavily on passive verses active planting (i.e. allowing the site to restore

naturally verses collecting plant material and growing species in the park’s greenhouse

for planting back at the disturbed site).

Prescribed fire may be used to maintain healthy native plant communities in some

habitat types. The combination of fire and elk browsing can negatively impact some

native plant communities such as aspen, upland shrub and willow (Nesvacil and

Olmsted, 2003, Connor et. al., 2003). For any prescribed fire, endangered, threatened

and rare species are considered. Fire can enhance some invasive exotic plants while

reducing populations of others. Burn units have to be inventoried and invasive exotic

species documented to determine where prescribed fire is appropriate. Also, known
69

endangered, threatened and rare species locations must be identified for fire personnel.

A prescribed fire, if applied correctly, would have a short-term minor impact on plant

and animal communities, but would have a long-term minor to moderate benefit

when those communities are restored to natural conditions.

Biological Control

The use of biological control insects (see Appendix H on page 141) should have no

impact on threatened, endangered or rare species. Biological control insects would be

carefully chosen to insure that they only feed on the invasive exotic plants to be

controlled. Native plant species are expected to benefit from the use of biological

control, which would also have a long-term benefit on threatened, endangered or rare

species by enhancing habitat.

Low Risk Method

There would be negligible short-term adverse impacts to threatened, endangered or

rare species of flora and fauna from using hot water or other low risk methods such as

natural biodegradable chemicals, or plastic sheeting. Hot water and other low risk

methods could impact a rare plant if applied directly to that plant, so it is imperative

that rare plant locations are identified and avoided when controlling invasive exotic

plants using these techniques. One hot water machine uses a foam composed of 100%

plant sugars. The foam formula would not have any secondary effect on rare plants

from residue. The foam formula is EPA registered as a low risk natural herbicide and

quickly biodegrades after application.

The hot water machines used to control exotic plants are noisy, and short-term

displacement of threatened, endangered or rare wildlife may occur when they are in

operation. The Northern goshawk is likely to be the only specie that has the potential to

be displaced when the machine is in use. Northern goshawks are likely to avoid using

open meadows for foraging when a hot water machine is in use. It is very unlikely that

threatened, endangered or rare wildlife would abandon an area due to short-term noise

generated by a hot water machine, but some species could be temporarily displaced

while the machine is in use. A hot water machine would probably not be used near the

threatened greenback cutthroat trout or Colorado River cutthroat trout because of

accessibility limitations. However, low risk natural chemicals may be used by wick or

wand applicators near water, but impacts are expected to be negligible.

Impacts of Alternative 2 on Endangered, Threatened, and Rare Species

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

RMNP would use the least toxic synthetic herbicide only as a last resort after trying

other IPM techniques. Monitoring at RMNP indicates that some invasive exotic

species have exceeded defined threshold levels and are not currently being effectively

controlled using the other IPM techniques. Synthetic herbicide use has the potential to

create a short-term minor impact to endangered, threatened or rare species.

Herbicides have the potential to enter systems and some can bioaccumulate in wildlife,
70

though the herbicides proposed for use in RMNP are considered low-risk and should

not bioaccumulate. Synthetic herbicides would not be used in boreal toad habitat or

near native Greenback cutthroat or Colorado River cutthroat trout. Contamination of

sensitive plant species because of runoff or drift is unlikely except when heavy rainfall

occurs soon after application. For this reason, herbicides would not be applied when

rainfall is imminent, with the exception of Paramount, which requires adequate soil

moisture and/or a light rain for soil uptake. Paramount is proposed for only field

bindweed. All known locations of field bindweed are not near rare plant, boreal toad or

threatened or endangered fish habitat.

Herbicide treatments can present some risks, especially for rare plants. RMNP has

been documenting the location of rare plant species within the park. Presently there are

only two known populations of rare plants that are located near invasive exotic plants

(DBG 2000). One is threatened by musk and Canada thistle and the other by invasive

grasses. No chemicals (natural or synthetic) would be used near these two locations of

rare plants. If rare plants are found among invasive exotic plants proposed for control

by either natural or synthetic chemical means, further review would be required prior to

chemical use. The potential impacts to the rare plants would be reviewed by NPS

Intermountain Regional Wildlife and Plant Specialists and by the Intermountain Region

IPM Specialist. If federally listed or candidate species are involved, the NPS would

consult with the U.S. Fish and Wildlife Service (FWS).

With the implementation of mitigation measures (please see page 104) the risk of

impacting T&E species and rare plants with chemical control would be reduced to a

negligible level.

Long-term persistence of herbicides in the food chain, and subsequent toxic effects, is

not expected to occur in RMNP. This is primarily due to the chemicals proposed for

use, the rates at which they would be applied, and the quantities proposed to be used.

The chemicals proposed for use do not contain organo-chlorines that can cause eggshell thinning and other harmful effects to wildlife.

For the typical concentrations of herbicides proposed for use, the risk to fish and

aquatic organisms is low. There is no proposal to use herbicides in or near greenback

cutthroat trout habitat. Implementation of mitigation measures for protection of water

quality can effectively minimize or eliminate most impacts to the aquatic environment,

which includes habitat for the federally threatened greenback cutthroat trout and rare

Colorado River cutthroat trout. Table 8 presents the impacts of synthetic herbicides

proposed for use in RMNP to threatened, endangered or rare wildlife. Impacts to

vegetation are also discussed in Table 6 on page 53.
71

Table 8 - Impact of Synthetic Herbicides on Threatened, Endangered and Rare

Species

Herbicide/Active

Ingredient

Impacts of the Herbicide on Threatened, Endangered and Rare

Species

Redeem R&P

(Triclopyr

&Clopyralid)

Contact with non-target sensitive plants may injure or kill them. Avoid drift

around known locations of sensitive plants by establishing buffer zones. It

has low toxicity to fish. It rapidly breaks down in water to a less toxic form.

It is not known to accumulate in fish. It is slightly toxic to nontoxic to

invertebrates. It is slightly toxic to mammals, and mammal species that feed

on short grasses are the most susceptible to possible acute impact from the

use of triclopyr TEA and BEE above 3.0 lb ae/A. RMNP proposes to use

Redeem at 1.5 ozs. per acre. Although the persistence of triclopyr acid/anion

on avian food items is unknown, it is possible environmental concentrations

would remain high enough for sufficient duration to produce some chronic

effect(s) when triclopyr is used at higher amounts. The triclopyr degradate,

TCP, is more toxic than the TEA or tricolpyr acid and is similar to BEE in

acute toxicity to fish. The EPA is currently requiring additional confirmatory

data to better characterize the fate and chronic toxicity to fish of triclopyr

degradate TCP. Mammals excrete most of it unchanged in urine. It has low

toxicity to birds and is nontoxic to bees. It has not been tested for chronic

effects in terrestrial animals. In an eight-day dietary study on birds, the LC50

ranged from 2,935 to greater than 5,000 ppm.

2,4-D Amine or 2,4-

D Ester (LVE)

It is highly toxic to non-target plants and must be used with extreme caution

around known endangered, threatened, rare or other non-target plants. Buffer

zones are imperative. 2,4-D when used in large amounts can bioaccumulate

in animals. However, the amount of 2,4-D proposed for use in RMNP should

not be enough to bioaccumulate in animals. 2,4-D Amine and Ester are

generally nontoxic to fish. LC50 levels for bluegill, sunfish, and rainbow

trout are 263 and 377 mg/L, respectively (Tu et al., version April 2001). 2,4-

D forms range from being practically nontoxic to moderately toxic to birds.

It is relatively nontoxic to honey bees. Mammals have moderate sensitivity

to 2,4-D exposure, and it should be used with caution around known locations

of endangered, threatened, or rare animals. Toxic effects were noted in tested

animal’s kidneys at low dosages in two-year dietary tests in mice and rats.

Some animals such as dogs are significantly more sensitive to 2,4-D organic

acids than are rats and humans, which means species such as coyotes, fox and

other similar native mammals may be sensitive. RMNP currently has no

known population of T&E listed species such as the lynx or gray wolf. It

may cause eye damage and skin irritation to animals that come in contact

with 2,4-D formulations. 2,4-D formulations were not mutagenic in most

studies.

Transline

(Clopyralid)

Contact with non-target plants may injure them, so Clopyralid should be used

with caution around known threatened, endangered or rare plants. It has low

toxicity to fish and aquatic invertebrate animals. It does not bioaccumulate in

fish tissues. It has low toxicity to birds and mammals and is not toxic to bees.

However, clopyralid can cause severe eye damage to mammals including

permanent loss of vision. It is not classified as a carcinogen, teratogen,

mutagen, or reproductive inhibitor.
72

Herbicide/Active

Ingredient

Impacts of the Herbicide on Threatened, Endangered and Rare

Species

Roundup & Rodeo

(Glyphosate)

Contact with threatened, endangered or rare plants may injure or kill them so

non-target plants must be protected. Roundup and Rodeo have an

intermediate to acute toxicity to freshwater fish and aquatic invertebrates.

Glyphosate is practically nontoxic to birds and mammals. It is practically

nontoxic to bees but exposure to freshly dried Roundup killed over 50% of

three other speices of beneficial insects: a parasitic wasp, lacewing, and a

ladybug. The surfactant MONO818 included in Roundup may interfere with

cutaneous respiration in frogs and gill respiration in tadpoles and is highly

toxic to fish. RMNP will avoid using MONO818. Glyphosate and its

formulations have not been tested for chronic effects in terrestrial animals,

but does show blood and pancreatic effects during subchronic feeding studies

with rats and mice. Some studies indicate that glyphosate does not cause

genetic damage, but other studies have shown that both glyphosate and

glyphosate products are mutagenic. Glyphostate may be a hazard to

threatened, endangered or rare species if applied to areas where they live. The

Roundup and Rodeo formulations are two of only a few herbicides approved

for controlling weeds in delicate aquatic environments. Strongly absorbed to

suspended organic and mineral matter. Primarily broken down by

microorganisms.

Plateau (Imazapic) Plateau is not mutagenic or teratgenic and would not be expected to have any

adverse effect on wildlife. Plateau is considered nontoxic to mammals,

aquatic invertebrates and birds, but is of moderate toxicity to fish. Imazapic

is nontoxic to bees. It does not have the potential to “mimic” estrogen, nor

can it be considered an endocrine disrupter. It is considered nontoxic to

mammals through physical exposure or ingestion. If ingested, Plateau is

rapidly excreted in the urine and feces and does not bioaccumulate in

animals. It is also highly unlikely to move through the food chain. However,

no specific toxicology studies have been conducted on amphibians, though

impacts to these sensitive species should have no adverse effect based on

research on other species.

Tordon (Picloram) The preponderance of data shows Picloram to be non-mutagenic in ‘In vitro’

(test tube) tests and in animal test systems. However, one study found that

chromosome aberrations increased in frequency in hamster ovary cells

exposed to picloram. Some other recent studies show additional evidence of

mutagenicity. The herbicide is slightly to moderately toxic to aquatic

organisms on an acute basis (LC50/EC50 between 10 and 100 mg/L in most

senstive species). There is evidence that picloram is lethal to fish at a

concentration of 1 ppm. Picloram has very low toxicity to soil

microorganisms at up to 1,000 parts per million. Picloram is almost nontoxic

to birds. It is relatively nontoxic to bees. Picloram is low in toxicity to

mammals; animals excrete most picloram in the urine, unchanged. Picloram

may be a hazard to threatened, endangered or rare plants when used on or

near them. Known locations of threatened, endangered or rare plants should

be avoided and a buffer zone established around them. Picloram may be a

hazard to some endangered invertebrates if it is applied to areas where they

live. There are no federally threatened or endangered invertebrates in the

park, but there are rare insects and one rare capshell snail. Picloram would

not be used near known capshell populations. It is not expected to be a
73

Herbicide/Active

Ingredient

Impacts of the Herbicide on Threatened, Endangered and Rare

Species

hazard to other threatened, endangered or rare animals.

Paramount

(Quinclorac)

It is not classified as a carcinogen, teratogen, mutagen, or reproductive

inhibitor. It is considered practically nontoxic to avian species, fish, aquatic

invertebrates, and honey bees. Avian and aquatic studies show no significant

effects. It does not bioaccumulate in animals. It is not considered an

estrogen disrupter and is rapidly excreted in urine. No adverse effects to

threatened, endangered, rare or other wildlife are expected from the use of

this herbicide. Application should be by a backpack sprayer for bindweed

patches to minimize drift and consequential impact to adjacent native plants.

Escort (Metsulfuron

methyl)

Contact with non-target sensitive plants may injure or kill them. It is

practically nontoxic to fish and aquatic invertebrates. It does not

bioaccumulate in fish. It is practically nontoxic to birds and mammals. It is

practically nontoxic to bees. It may be a hazard to threatened, endangered or

rare plants, and has to be used around known locations of these plants with

extreme caution, and buffer zones must be established. It is not considered a

hazard to endangered, threatened or rare animals.

Telar

(Chlorsulfuron)

Contact with endangered, threatened or rare plants may injure or kill them so

must be used with extreme caution around known locations of non-target

and/or sensitive plants. Buffer zones will be established. It is practically

nontoxic to most fish and aquatic invertebrate animals. It does not

bioaccumulate in fish. It is practically nontoxic to birds and mammals. It is

not considered a hazard to threatened, endangered or rare species or other

species of animals. Should be used with caution near any known locations of

sensitive wildlife. It is not known to be carcinogenic to animals.

Summary of Impacts on Endangered, Threatened and Rare Species

Alternative 1 would result in some long-term benefits to endangered, threatened and

rare species, but at a lower level than Alternative 2. Some invasive exotic plant

species, such as leafy spurge, yellow toadflax, or field bindweed cannot be effectively

controlled without the use of synthetic herbicides. Alternative 1, because of its limited

ability to control exotic plants, does pose some risk because of the potential loss of

native flora and fauna, biodiversity and habitat, which could have a negative impact on

threatened, endangered and rare species.

Alternative 2 would result in the greatest long-term benefit to threatened, endangered

and rare species. By effectively controlling invasive exotic plants, there would be an

increase in the availability of habitat for breeding, nesting, and feeding for fauna and a

decrease in competition between native flora and exotic plants.

Synthetic herbicide treatments can present some risks to threatened, endangered and

rare species, especially for plants. The herbicides and amounts proposed for use in

RMNP are expected to pose little risk to animals, but could be a risk to rare plants.

With the implementation of mitigating measures (please see page 104, mapping of

known locations of rare plants, and establishing buffer zones, the risk would be kept to

a minimum. Being proactive versus reactive in preventing the spread of invasive exotic
74

plants would be a long-term moderate benefit to threatened, endangered or rare

species.

Cumulative Impacts

Previous impacts to endangered, threatened and rare species in areas proposed for

invasive exotic plant control are due to the presence of earlier anthropic disturbances

such as livestock grazing and haying, water diversions and irrigation, cultivation of

grassland meadows, mining, settlements, lodges, camps and cabins, a downhill ski area,

a nine hole golf course, intensive grazing by native ungulates, hunting, park

development activities and continuing visitor use. Previous invasive exotic plant

control has resulted in negligible cumulative impacts to endangered, threatened and rare

species. The anthropic disturbances varied considerably as to type, intensity, and

duration before and after the park was established.

Alternative 1 would have a negligible to minor cumulative impact to endangered,

threatened and rare species due primarily to areas being surveyed for these species

before control occurs. Alternative 1, which would result in a continuation of current

management practices for managing invasive exotic plants, has not been effective at

controlling the spread of some invasive species such as yellow toadflax, field bindweed

and leafy spurge. If these exotic plant species continue to spread within the park,

additional mechanical, cultural and low-risk control would be required, which would

create additional cumulative impacts to endangered, threatened or rare species.

Alternative 2 would have a negligible to minor cumulative impact to endangered,

threatened and rare species. It is anticipated that troublesome invasive exotics plants

would decrease as the full range of IPM techniques are implemented. As native

vegetation is restored and habitat improves, cumulative impacts to endangered,

threatened and rare species would be ameliorated.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to endangered, threatened or rare

species whose conservation is: 1) necessary to fulfill specific purposes identified in the

enabling legislation of RMNP; 2) key to the natural or cultural integrity of the Park; or

3) identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.

Wildlife

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts were derived from all available

information on wildlife. Map locations of sensitive resources were compared with

known invasive exotic plant populations. Predictions about short- and long-term site

impacts were based on existing inventory and monitoring data from RMNP. The

thresholds of change for the intensity of impacts to wildlife are defined as follows:

• No impact ñ There is no discernable impact
75

• Negligible ñ The impact could result in a change to a population or individuals of a

species or resource but the change would be so small that it would not be of any

measurable or perceptible consequence.

• Minor ñ An action that could result in a change to a population or individuals of a

species or a resource. The change would be small and localized and of little

consequence.

• Moderate ñ An action that would result in some change to a population or

individuals of a species or resource. The change would be measurable and of

consequence to the species or resource but more localized.

• Major ñ An action that would have a noticeable change to a population or

individuals of a species or resource. The change would be measurable and result in

a severely adverse or major beneficial impact, with possible permanent

consequences for the species or resource.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Wildlife

Mechanical Control

Removing invasive exotic plants by using tools (including mowing and the use of string

trimmers) would have a negligible adverse impact on wildlife. Some soil erosion and

loss of native plants may occur at the base of an invasive exotic plant if it is dug from

the ground, resulting in a negligible loss of habitat. If a large patch is removed this

could increase the potential impact to some wildlife, but this impact is still considered

negligible.

Native vegetation is expected to recover when invasive exotic plants are removed,

benefiting wildlife in the long-term. Cutting seed heads and cutting plants at ground

level has no effect on wildlife in the short-term, but would have a beneficial effect in

the long-term. There may be short-term displacement of wildlife in the vicinity of

exotic plant management operations.

Mechanical treatment is labor intensive and will often require periodic retreatment for

many of the 35 invasive exotic plants. Therefore, the impacts from mechanical

treatment can be recurring.

Cultural Control

Restoring native vegetation through revegetation efforts is expected to result in a longterm benefit to wildlife. Restoring disturbed plant communities to natural conditions

enhances wildlife habitat.

Prescribed fire can cause the spread of some invasive exotic plants while reducing

populations of others. The combination of fire and elk browsing on the elk winter

range can negatively impact some wildlife habitat such as aspen, upland shrub and

willow plant communities (Connor, et.al. 2003, Nesvacil and Olmsted, 2003).
76

Prescribed fires for invasive exotic plant control will not occur in these habitat types on

the elk winter range until the park has developed and approved an Elk and Vegetation

Management Plan that would determine how these habitat types should be managed.

For any prescribed fire, wildlife resources (snags with tree cavities, for example) are

considered and protected to the degree possible. Burn units have to be inventoried and

invasive exotic species documented to determine where fire should or should not be

applied. A prescribed fire has short-term adverse impacts on wildlife, but long-term

benefits to wildlife when plant communities are restored.

Biological Control

The biological control insects proposed for use in RMNP should have no impact on

wildlife, and the long-term benefit of using biocontrol insects should enhance wildlife

habitat. There is a possible long-term risk that some biocontrol insects could evolve

over the long-term and have a negative impact on native flora and fauna. Some native

insects may be displaced from the use of biocontrol insects, but there is no

documentation to indicate that this will occur. Research is needed to substantiate this

potential impact.

Low Risk Methods

The use of hot water or other low risk methods including using natural chemicals would

result in short-term negligible impacts to wildlife, with long-term benefits resulting

from the removal of invasive exotic plants and the restoration of native plant

communities. One of the hot water machines uses a foam composed of 100% plant

sugars. The weed foam formula would not have any secondary effect on wildlife. Like

other natural chemicals, the foam formula does require registration as an natural

herbicide, but is known to quickly biodegrade after application.

The hot water machines are noisy, and short-term displacement of wildlife may occur

when wildlife are in the area during use. Due to potential impacts on elk and deer, the

use of a hot water machine may be limited during the calving and fawning season (late

May to mid-June). It is unlikely that wildlife would abandon an area from the noise,

but could be temporarily displaced. Some natural chemicals, such as Burn Out, could

have short-term impacts on some wildlife because of strong fumes. The fumes are

strongest during application, but quickly dissipate as the product dries. Some wildlife

may temporarily leave a treatment area.

Impacts of Alternative 2 on Wildlife

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

RMNP would use the least toxic synthetic herbicide only as a last resort after trying

other IPM techniques. Monitoring at RMNP indicates that some invasive exotic

species cannot be effectively controlled without using some synthetic herbicides.

Synthetic herbicide use has the potential to create a short-term minor impact to

wildlife species. Herbicides have the potential to enter systems, and some can

bioaccumulate in wildlife, though the herbicides and amount proposed for use in
77

RMNP should not bioaccumulate. Contamination of sensitive wildlife species because

of runoff or drift is unlikely except when heavy rainfall occurs soon after application.

For this reason, herbicides would not be applied when rainfall is imminent, with the

exception of Paramount, where adequate soil moisture and/or light rain is important for

soil uptake.

Implementation of mitigation measures requiring the use of buffer zones (please see

page 104) would help protect aquatic organisms and wildlife species that utilize

riparian habitat for food and shelter. Implementation of mitigation measures associated

with the protection of wildlife would effectively eliminate any negative impact.

Synthetic herbicides would not be applied by spraying within 100 feet of aquatic,

wetland or riparian areas. On a limited basis, synthetic herbicides could be applied

within 100 feet of aquatic, wetland or riparian areas with a wick or wand applicator.

Applying any synthetic chemical near aquatic, wetland or riparian areas would require

approval through the RAVE scoring system and by the Intermountain Region IPM

Coordinator.

Table 8 on page 71 presents the potential impacts to threatened, endangered or rare

wildlife species from the various chemicals proposed for use in RMNP. This

information also applies to non-listed wildlife species.

Summary of Impacts on Wildlife from the Alternatives

Alternative 1 would result in some long-term beneficial effects to wildlife but with a

moderate risk to wildlife because some invasive exotic plants would not be effectively

controlled. Negative impacts to wildlife habitat from invasive exotic plants may

increase under this alternative. Fumes from natural chemicals, such as the product

Burn Out, could temporally displace some wildlife.

Biocontrol species may have potential long-term secondary impacts on native species

and should be carefully evaluated before they are selected for use in RMNP. For

example, one species of seed-head weevil introduced to control musk thistle outside the

park immigrated into RMNP (Louda et al. 1997, 1998). Due to its wide diet breadth, it

is now found on native thistles and is causing negative impacts. The seed-head weevil

is also displacing native species of insects that use native thistles in their lifecycle.

Another insect recently released in the United States to control Canada thistle is also

known to impact native thistles, and there is a possibility that it could migrate to the

park (Svata Louda, personal communication). None of the biocontrol insects proposed

for release in this Plan/EA are expected to cause similar problems.

Alternative 2 would have the greatest long-term benefits to wildlife. Existing native

species would remain unimpaired and the danger of some species becoming extirpated

due to aggressive exotic plants would be removed. Negative impacts to wildlife habitat

from invasive exotic plants would decrease under this alternative. Negative impacts

from the use of synthetic herbicides are also expected to decrease as the number of

acres needing treatment decreases. Once invasive exotics identified for chemical

control are below identified threshold levels, synthetic herbicides would not be used.

Natural processes critical for creating and maintaining wildlife habitat (such as fire)

may be restored in ponderosa pine savanna by an increase in native understory
78

vegetation. However, heavy elk grazing is affecting native understory vegetation and is

influencing fire more significantly than invasive exotic plants.

Some wildlife would be temporarily displaced during control operations in the shortterm, but would benefit in the long-term. Extreme caution would be used during

herbicide applications, and wetlands would be avoided to minimize possible negative

impacts to wildlife, including invertebrates and aquatic species.

Cumulative Impacts

Previous impacts to wildlife in areas proposed for invasive exotic plant control are due

to the presence of earlier anthropic disturbances such as livestock grazing and haying,

water diversions and irrigation, cultivation of grassland meadows, mining, settlements,

lodges, camps and cabins, a downhill ski area, a nine hole golf course, hunting, visitor

use, and park development activities. Previous invasive exotic plant control has

resulted in negligible cumulative impacts to wildlife. The anthropic disturbances varied

considerably as to type, intensity, and duration before and after the park was

established.

Alternative 1 would have a short-term negligible to minor cumulative impact to

wildlife due primarily to temporary displacement while exotic plant control activities

are being conducted. However, Alternative 1 may not be effective at controlling some

aggressive invasive noxious weeds like spotted knapweed, yellow toadflax, field

bindweed, and leafy spurge resulting in a long term moderate cumulative impact. If

some exotic plant species continue to spread within the park, additional mechanical,

cultural and low-risk control would be required. This would cause additional

cumulative impacts to wildlife.

Alternative 2 would have a short-term negligible to minor cumulative impact to

wildlife. It is anticipated that troublesome invasive exotics plants would decrease as

the full range of IPM techniques are implemented resulting in a long-term moderate

benefit to wildlife. As native vegetation is restored and habitat improves, cumulative

impacts to wildlife would be ameliorated.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to wildlife whose conservation is: 1)

necessary to fulfill specific purposes identified in the enabling legislation of RMNP; 2)

key to the natural or cultural integrity of the Park; or 3) identified as a goal in the

Master Plan (1976) or other relevant NPS planning documents, there would be no

impairment of the Park’s resources or values if either Alternative 1 or 2 is selected.

Wilderness

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts on wilderness were derived from park

files, minimum tool analysis and park staff’s observations of the effects of control

techniques. Predictions on short- and long-term site impacts were based on existing

inventory and monitoring data of invasive exotic plant locations from RMNP. The

thresholds of change for the intensity of impacts to wilderness are defined as follows:

• No impact ñ There is no discernable impact
79

• Negligible ñ The impact would be so small that it would not be of any measurable

or perceptible consequence.

• Minor ñ The impact is slight but would be small and localized and of little

consequence.

• Moderate ñ The impact is readily apparent, would be measurable and

consequential, but more localized.

• Major ñ The impact is severely adverse or exceptionally beneficial. The change

would be measurable and the consequences could be permanent.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Wilderness

Mechanical Control

Presently there are no known invasive exotic plants in designated wilderness within the

boundaries of the park. There are infestations of invasive exotic plants in

recommended wilderness, and removing them using tools would have short-term

minor impacts. Mechanized string trimmers could cause an impact in recommended

wilderness primarily due to noise. A minimum tool analysis would be conducted and

must be approved by the RMNP Wilderness Coordinator before mechanized equipment

can be used in recommended or designated wilderness. Tractors or ATVs would not be

allowed in any recommended or designated wilderness.

Cultural Control

Restoring disturbed plant communities to natural conditions by revegetating disturbed

sites would have a long-term minor benefit on wilderness. Any vegetation restoration

project in wilderness is required to follow Class I area revegetation guidelines as

described in the Vegetation Restoration Management Plan for RMNP (McLendon &

Redente, 1994).

Prescribed fire and wildland fire for resource benefit could be used to maintain healthy

native plant communities in some habitat types within recommended or designated

wilderness. Fire is a natural component of habitats within RMNP, but has been

suppressed for more than 75 years. Fire suppression has affected native vegetation in

montane habitats such as densely forested ponderosa pine and aspen, where the natural

fire return interval is every 22 to 308 years. In more open ponderosa pine woodlands,

fire suppression has had less of an impact (William Baker, personnel communication).

However, for most of the forested areas of the park, which includes lodgepole pine and

spruce fir, the fire return interval has not been substantially altered, and remains within

the natural fire regime.

Fire can cause some exotic plant species to spread while reducing the population of

others. Prescribed fire burn units and invasive exotic treatment areas would be

inventoried and invasive exotic species documented to determine where fire should or

should not be applied. A correctly applied prescribed fire if applied correctly would
80

have a short-term minor negative impact on wilderness, but would have a long-term

benefit when plant and animal communities and the ecological balance are restored.

Biological Control

The biological control insects proposed for use in RMNP (see Appendix H on page

141) should have no effect on wilderness. Using biocontrol insects to control some

invasive exotic plants could result in long-term benefits to wilderness. There is a

potential risk that some biocontrol insects could evolve over the long-term and have a

negative impact on native flora and fauna and consequently on wilderness.

Low Risk Methods

Impacts to wilderness from using hot water or other proposed low risk methods are

considered to be negligible to minor with long-term benefits. Machines for hot water

application cannot be used in recommended or designated wilderness except along the

boundary where a hose could be extended. The wilderness experience for some visitors

would be affected for the short-term if within hearing distance of a hot water machine.

The noise of the machine is not expected to be noticeable beyond 650 feet. Natural

chemicals would be applied using a backpack sprayer or perhaps a unit mounted on a

horse. Using plastic sheeting would have to be evaluated by the minimum tool analysis

on a case by case basis to determine if it was an appropriate method of control in

wilderness.

Impacts of Alternative 2 on Wilderness

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

Specific chemical impacts to natural resources such as wildlife, endangered, threatened

or rare species, aquatic resources, air, soil and vegetation are discussed elsewhere in

this EA, and would apply to those resources in recommended or designated wilderness

areas.

The use of synthetic herbicides may temporarily have a minor impact on

recommended or designated wilderness. Herbicides have the potential to enter systems.

Contamination of sensitive habitat or wildlife in recommended or designated

wilderness because of runoff or drift is unlikely except when heavy rainfall occurs soon

after application. For this reason, herbicides would not be applied when rainfall is

imminent, with the exception of Paramount, where adequate soil moisture and/or light

rain is important for soil uptake. However, Paramount is not likely to be used where it

could affect wilderness because there are no field bindweed patches located in

recommended or designated wilderness.

Implementation of mitigation measures, including the use of buffer zones (please refer

to the mitigation measures on page 104) would help protect aquatic organisms and

species that utilize riparian habitat for food within recommended or designated

wilderness.

Summary of Impacts to Wilderness from the Alternatives

Alternative 1 would result in short-term minor beneficial effects to wilderness. This

alternative is likely to result in long-term moderate negative impacts from some
81

invasive exotic plants that cannot be effectively controlled using mechanical, cultural,

biological or low risk control techniques. RMNP’s goal would be to aggressively

control invasive exotic plants in areas outside recommended or designated wilderness

to prevent the spread of invasive exotic plants into recommended or designated

wilderness. However, Alternative 1 would not stop the spread of some invasive exotic

plants already established in recommended wilderness.

Alternative 2 would have the greatest long-term moderate benefits to recommended

or designated wilderness as compared to Alternative 1. The long-term integrity of

wilderness values would be protected and enhanced. RMNP’s goal is to aggressively

control invasive exotic plants in areas outside recommended or designated wilderness

to prevent the spread of invasive exotic plants into recommended or designated

wilderness. Presently, most of the 427 acres of land infested with invasive exotic plants

occurs outside recommended wilderness, and no known invasive exotic plants occur in

designated wilderness. Synthetic herbicides would be used on 65.25 acres of the 427

acres infested with invasive exotic plants, and most of the acres proposed for treatment

with synthetic herbicides are located outside recommended wilderness. A large

percentage of recommended wilderness (>99 percent) would remain chemical free.

Mechanical and chemical control may impact wilderness values in the short-term, but

would benefit wilderness values in the long-term. The minimum tool concept would be

used for exotic plant management activities that are proposed to occur in wilderness or

recommended wilderness. No vehicle, such as a tractor or ATV, would be allowed in

recommended or designated wilderness. Backpack sprayers or a sprayer mounted on a

horse may be used to chemically treat invasive exotic plants in recommended

wilderness, or in designated wilderness should it become necessary in the future due to

a new infestation. However, by being proactive, it is anticipated that invasive exotic

plants will not become a problem in wilderness areas.

Cumulative Impacts

Previous impacts to wilderness in areas proposed for invasive exotic plant control are

due to the presence of park visitors, earlier anthropic disturbances such as livestock

grazing and haying, water diversions and irrigation, cultivation of grassland meadows,

mining, settlements, lodges, camps and cabins, a downhill ski area, a nine hole golf

course, hunting and park development activities. Previous invasive exotic plant control

has resulted in negligible cumulative impacts to wilderness. The anthropic disturbances

varied considerably as to type, intensity, and duration before and after the park was

established.

Alternative 1 would have a negligible to minor short-term cumulative impact to

wilderness in specific areas of the park primarily due to mechanical control such as

hand pulling and digging. Motorized vehicles would not be allowed in wilderness.

However, Alternative 1 may not be effective at controlling some aggressive invasive

noxious weeds like spotted knapweed, yellow toadflax, field bindweed, and leafy

spurge. The continued spread of these species could cause a long-term moderate

cumulative impact to wilderness. Likely effects include increased soil erosion, loss of

native plant biodiversity and wildlife habitat. If exotic plants continue to spread in
82

wilderness, additional mechanical, cultural and low-risk control would be required,

which would create additional cumulative impacts to wilderness.

Alternative 2 would have a negligible to minor short-term cumulative impact to

wilderness with a long-term moderate benefit. It is anticipated that troublesome

invasive exotics plants would decrease as the full range of IPM techniques are

implemented. As native vegetation is restored and habitat improves, cumulative

impacts to wilderness would be ameliorated.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to designated or recommended

wilderness whose conservation is: 1) necessary to fulfill specific purposes identified in

the enabling legislation of RMNP; 2) key to the natural or cultural integrity of the Park;

or 3) identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.

Air Quality

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts from the effects of control techniques on

air quality were derived from park files and literature cited in this plan. The thresholds

of change for the intensity of impacts to air quality are defined as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact would be so small that it would not be of any measurable

or perceptible consequence.

• Minor ñ The impact is slight but would be small and localized and of little

consequence.

• Moderate ñ The impact is readily apparent, would be measurable and

consequential, but more localized.

• Major ñ The impact is severely adverse or exceptionally beneficial. The change

would be measurable with possible permanent consequences.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Air Quality

Mechanical Control

Removing invasive exotic plants using tools would have negligible impacts on air

quality. The greatest impact would be localized air pollution from the use of gasoline

powered string trimmers or mowers that would cause some dust and exhaust emissions.

This would have a short-term localized negligible impact on air quality.

Mechanical treatment is labor intensive except for small invasive exotic plant

infestations. Because mechanical treatment does not always remove all of the exotic
83

plants in an infested area, periodic retreatment is often required. Therefore, impacts

from mechanical treatment can be recurring.

Cultural Control

Protecting and restoring native plants through active or passive revegetation efforts has

a negligible beneficial impact on air quality by stabilizing soil, which reduces dust.

Fire is a natural component of the ecosystem within RMNP, but has been unnaturally

suppressed in some areas of the park over a period of many years. Prescribed fires and

wildland fires for resource benefit would be used to maintain healthy native plant

communities in some habitat types. State smoke permits are required for any

prescribed fire, and prescriptions are designed to minimize smoke impacts (Jesse

Duhnkrack, personal communication). Impacts to air quality from smoke are addressed

in the park’s 1992 Fire Management Plan and EA, and the 2002 Wildland-Urban

Interface Fuels Management EA. A correctly applied prescribed fire would only have a

short-term localized minor adverse impact on air quality, but would result in a longterm minor benefit when plant and animal communities are restored and the

ecological balance of fire is restored.

Biological Control

Biological control would have no impact on air quality.

Low Risk Methods

Impacts to air quality from the use of hot water or other low risk methods are

considered to be negligible to minor. A tractor or ATV might be used to transport a

hot water machine, and a tractor or ATV could be used to apply a natural chemical if an

invasive exotic species covered a large area outside recommended or designated

wilderness. Trucks, tractors and ATVs use fossil fuels. The machine that produces the

hot water burns either propane and/or gasoline. Emissions would have a short-term

localized negligible impact on air quality in the park. The product Burn Out produces

fumes that can have a short-term localized impact on air quality, which could impact

humans and wildlife.

Impacts of Alternative 2 on Air Quality

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

The use of synthetic herbicides can pose a short-term minor adverse impact to air

quality, principally from drift. Impacts to air quality can be reduced by limiting

spraying to days when the air is calm, or the wind speed is less than that indicated on

the label (please refer to the mitigation measures on page 104).

Conducting prescribed fires on land that has been previously treated with an herbicide

can be problematic. Chemicals released into the air through burning could be carried in

air currents for some distance beyond the treated area, which could pose a health risk to

employees conducting the burn and/or the public. It is important that chemical

application be coordinated with prescribed fires. Areas treated with a chemical should

not be burned for a time. An area may be treated with a chemical after a prescribed

fire, but not before. The length of time that an herbicide would remain active and
84

thereby available for re-release if a fire occurred depends on the herbicide used. Table

9 addresses air quality issues for the chemicals we propose to use. Most chemicals

should not be a concern three to four months after application, but some residue could

last for up to one year. To air on the side of caution, our goal would be to apply a

synthetic herbicide at least one year ahead of a planned prescribed burn or two or more

months after a burn. Close coordination with the park’s Fire Management Officer and

his staff is essential to maintain the safety of park employees, visitors and park

neighbors. With a successful weed management program, the use of chemicals can be

significantly reduced over time, which would help to minimize the impact of chemicals

on air quality.

If the use of herbicides is approved, areas where chemicals are to be applied would be

identified using signs, and made known to fire management personnel. In the event a

wildland fire occurs following chemical application, chemicals could be released into

the air. Most areas where chemicals are proposed for use are in relatively safe open

meadows, which are not often threatened by wildland fires.

Implementing mitigating measures for chemical application, such as the size of the

spray nozzle, distance to the ground, no aerial application, etc., would minimize air

quality impacts (please refer to the Mitigation Measures on page 104).

The use of tractors or ATVs for chemical application could occur, which in turn would

have a short-term localized negligible adverse impact on air quality from exhaust

emissions or dust.

Table 9 - Impact of Synthetic Herbicides on Air Quality

Herbicide/Active

Ingredient Impacts on Air quality

Redeem R&P

(Triclopyr &

Clopyralid)

Avoid drift. Triclopyr does not evaporate easily, volatilization is

negligible on the soil surface, and photolysis does not occur. It

degrades to CO2 and organic matter. The relatively small amount of

CO2 released into the air from the amounts of Triclopyr proposed for

use in RMNP would have a negligible impact on air quality. There is

no information available on potential by-products produced from

burning treated vegetation.

2,4-D Amine or

2,4-D Ester

Avoid drift. Average persistence of phytotoxicity is generally 1-4

weeks. Volatilization is considered to be minor (typically negligible)

for amine or LVE in the field. Isooctyl esters are considered lowvolatile esters. Oil-soluble amines are considered the least volatile.

The burning of vegetation treated with 2,4-D Amine has not generated

detectable 2,4-D by-products in the field.

Transline

(Clopyralid)

Avoid drift. Volatilization produced insignificant losses. It does not

evaporate easily. However, the potential to volatilize increases with

increasing temperature, increasing soil moisture, and decreasing clay

and organic matter content. Clopyralid is not degraded significantly

by sunlight and the photolysis half-life in soil is >12 years. There is no

information available for the potential for by-products from burning

treated vegetation. Potential for adverse health effects from contacting
85

Herbicide/Active

Ingredient Impacts on Air quality

treated vegetation are below expected exposure levels that could cause

harmful effects.

Roundup & Rodeo

(Glyphosate)

Avoid drift. Studies documented about a 10% mortality of seedlings

for noncrop plants downwind at 66 feet from where Glyphosate was

applied by a tractor. Volatilization produced negligible losses. It does

not evaporate easily. Potential by-products from burning treated

vegetation include phosphorus pentoxide, acetonitrile, carbon dioxide

and water. Phosphorus pentoxide forms phosphoric acid in the

presence of water. None of these compounds are known to be a health

threat at the levels which would be found in a vegetation fire.

Plateau (Imazapic) Avoid drift. It does not evaporate easily, and volatilization is

negligible on the soil surface. Photolysis does not occur. A study was

conducted in 1988 with a prescribe fire occurring 30 to 106 days after

herbicide application and no herbicide residues were detected in the

smoke. The herbicide residue detection limits were several hundred to

several thousand times below occupational exposure limits to

herbicides.

Tordon (Picloram) Avoid drift. Picloram does not easily evaporate. More than 95% of

picloram residue is destroyed during burning. There were no losses

from volatilization. There have been no identified by-products from

burning treated plants in the field, though by-products have been

identified in laboratory experiments. Carbon dioxide is the major endproduct of the breakdown of Picloram in soil. The relatively small

amount of CO2 released into the air from the amounts of picloram

proposed for use in RMNP would have a negligible impact on air

quality.

Paramount

(Quinclorac)

Avoid drift. Volatilization produced negligible losses. It does not

evaporate easily. Photo degradation on the soil surface was slight to

negligible. No studies have been done with Quinclorac to determine

the potential residues in smoke resulting from burning after herbicide

application. A study was conducted in 1988 with a prescribe fire

occurring 30 to 106 days after herbicide application and no herbicide

residues were detected in the smoke. The herbicide residue detection

limits were several hundred to several thousand times below

occupational exposure limits to herbicides.

Escort

(Metsulfuronmethyl)

Avoid drift. It is broken down by microorganisms and chemical hydrolysis to

nontoxic and nonherbicidal products. Volatilization produced insignificant

losses and it does not evaporate easily. There was insufficient information

available for determining by-products from burning treated vegetation.

Expected exposure levels from coming into contact with treated vegetation

are below the lowest level that would cause harmful effects.

Telar

(Chlorsulfuron)

Avoid drift. There were negligible loses from volatilization. There is no

information available for the potential for by-products from burning treated

vegetation.
86

Summary of Impacts to Air Quality from the Alternatives

Alternative 1 would have negligible to minor impacts on air quality from gasolinepowered equipment or prescribed fire. A truck, tractor or ATV would have some minor

localized impacts on air quality from emissions or dust.

Alternative 2 would have a short-term minor local impact on air quality because of

drifting, but volatilization of herbicides should not be a problem given the proposed

application methods within the park. We do not plan on applying any chemical by

fixed wing aircraft or by a helicopter. Chemicals would be applied with ground-based

equipment at a height of less than three feet above the ground. Chemicals would not be

applied when the wind is stronger than 3 mph. Air quality impacts can be further

reduced by requiring that a surfactant be mixed with herbicides (reduces drift) in

addition to other mitigation measures (please refer to page 104).

Herbicide applications would be done at least one year ahead of a prescribed burn, or

two or more months after a burn. Close coordination with the park’s Fire Management

Officer would help to ensure the safety of park employees, visitors and park neighbors.

Cumulative Impacts

Existing impacts to air quality in areas proposed for invasive exotic plant control are

primarily due to pollutants originating from outside the park. Pollutants originating

inside the park have a negligible to minor cumulative impact on air quality. The

combined impact of past and present actions, and the implementation of Alternative 1

or 2 would have a negligible cumulative impact on air quality. Mitigation measures

associated with the application of herbicides are designed to minimize impacts to air

quality.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to air quality whose conservation is:

1) necessary to fulfill specific purposes identified in the enabling legislation of RMNP;

2) key to the natural or cultural integrity of the Park; or 3) identified as a goal in the

Master Plan (1976) or other relevant NPS planning documents, there would be no

impairment of the Park’s resources or values if either Alternative 1 or 2 is selected.

Cultural Resources

Invasive exotic plants may have long-term negative impacts on prehistoric sites due to

the altering of native vegetation and potential for increased soil erosion. This can lead

to erosion of cultural resources. In general, the removal of invasive exotic plants would

contribute to the restoration and maintenance of the historic and ethnographic cultural

landscapes in the park, especially around National Register sites such as the Never

Summer Ranch, McGraw Ranch and the National Historic Landmark Beaver Meadows

Visitor Center. Invasive exotic plants would be removed by mechanical and cultural

control techniques in these areas. All treatments around National Register Sites should

be planned and implemented in accordance with NPS-28 (USDI, 1993).

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts on cultural resources were derived from

park files, the park’s archeologist and other park staff’s observation of the effects of
87

control techniques. Predictions on sort- and long-term site impacts were based on

existing inventory and monitoring data from RMNP. The thresholds of change for the

intensity of impacts to cultural resources are defined as follows:

• No impact ñ There is no discernable impact. For purposes of Section 106, the

determination of effect would be no adverse effect.

• Negligible ñ Impact is at the lowest levels of detection – barely measurable

consequences, either adverse or beneficial, to prehistoric or historic resources. For

purposes of Section 106, the determination of effect would be no adverse effect.

• Minor ñ Adverse impact – site disturbance results in little, if any, loss of cultural

significance or integrity and the National Register eligibility of the site is

unaffected. For purposes of Section 106, the determination of effect would be no

adverse effect.

Beneficial impact –Exotic plant management activities result in maintenance and

preservation of a site. For purposes of Section 106, the determination of effect

would be no adverse effect.

• Moderate ñ Adverse impact – site disturbance does not diminish the cultural

significance or integrity of the site to the extent that its National Register eligibility

is jeopardized. For purposes of Section 106, the determination of effect would be

adverse effect.

Beneficial impact – Exotic plant management activities result in stabilization of a

site. For purposes of Section 106, the determination of effect would be no adverse

effect.

• Major ñ Adverse impact – site disturbance diminishes the cultural significance and

integrity of the site to the extent that it is no longer eligible to be listed in the

National Register of Historic Places. For purposes of Section 106, the

determination of effect would be adverse effect.

Beneficial impact – Exotic plant management activities result in maintenance and

preservation of a site. For purposes of Section 106, the determination of effect

would be no adverse effect.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Impacts of Alternative 1 on Cultural Resources

Mechanical Control

Ground disturbing activities, such as digging weeds, pulling weeds, or using a string

trimmer, could have a long-term minor adverse impact on cultural resources. In the

long-term, the removal of invasive exotic plants would have positive benefits for the

protection of prehistoric or historic sites by protecting and enhancing native plant

communities that stabilize the soil.
88

Cultural Control

Ground disturbing activities related to revegetation work (raking soil and digging in

new plants) could have a long-term negligible adverse impact on cultural resources.

Prescribed fires could also have an adverse negligible or minor impact on cultural

resources. Because of the potential for adverse impacts, revegetation work and

prescribed fires must be reviewed and approved by an archeologist before work occurs

in areas where there are documented cultural resources.

Biological Control

There would be no impact to cultural resources from the implementation of biological

control methods.

Low Risk Methods

A truck or ATV would be used to carry the hot water machine. These vehicles could

have a long-term negligible to minor adverse impact on prehistoric or historic sites.

Potential problem areas include open meadows outside of wilderness such as Moraine

Park, Upper Beaver Meadows, Horseshoe Park and Hollowell Park. An archeologist

would be consulted before an area is treated using hot water equipment or a natural

chemical, and known sites would be avoided.

Impacts of Alternative 2 on Cultural Resources

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

A tractor or ATV could be used to apply herbicides. Driving equipment over a

prehistoric site could have a long-term negligible to minor adverse impact. Areas

where a tractor or ATV are proposed to be used would be cleared with the park

archeologist prior to the start of any work. Potential problem areas include open

meadows such as Moraine Park, Upper Beaver Meadows, Horseshoe Park and

Hollowell Park.

Summary of impacts to cultural resources from the alternatives

Alternative 1 would result in minor adverse impacts to archeological sites caused by

mechanical control techniques, such as hand pulling, digging, mowing or using a string

trimmer. Equipment used to transport a hot water machine (either a truck or an ATV)

has the potential to cause minor adverse impacts to archeological resources. Cultural

control techniques (revegetation and prescribed fire) would be cleared by an

archeologist before work occurs, and known cultural sites would be avoided.

Alternative 2 would result in minor adverse impacts to cultural resources caused by

mechanical control techniques and the use of ATVs or tractors to haul hot water

equipment or chemical sprayers. Cultural resources would receive greater protection

under Alternative 2 when compared to Alternative 1 because all IPM control techniques

would be available. The most appropriate IPM control technique can be selected to

protect sensitive cultural resources from invasive exotic plants. The park archeologist

would be consulted prior to any herbicide application using a sprayer mounted on a

truck or an ATV and known cultural resources would be avoided.
89

Cumulative Impacts

Previous impacts to cultural resources in most areas proposed for invasive exotic plant

control are due to visitor use, past and present invasive exotic plant control and from

earlier anthropic disturbances that damaged or destroyed cultural resources, such as

water diversions, irrigation reservoirs and ditches, cultivation of grassland meadows,

mining, settlements, lodges, camps and cabins, logging, development of a downhill ski

area and a nine-hole golf course. Park development activities have also impacted

cultural resources. Use of the park by Native Americans dates back thousands of years.

The anthropic disturbances varied considerably as to type, intensity, and duration

before and after the park was established, and many developments within the park are

now culturally significant.

The implementation of Alternative 1 would have a negligible cumulative impact on

cultural resources primarily due to mechanical control, such as hand pulling and

digging. Some impacts to cultural resources could occur from motorized vehicles

driving in grassland meadows in front country areas if a low risk method like hot water

is used. It is anticipated that Alternative 1 may not be effective at controlling some

aggressive invasive noxious weeds like spotted knapweed, yellow toadflax, field

bindweed and leafy spurge. If some exotic plant species continue to spread within the

park, additional mechanical, cultural and low-risk control would be required, which

would create additional cumulative impacts to cultural resources.

Alternative 2 would have a negligible cumulative impact on cultural resources

primarily due to mechanical control, such as hand pulling and digging. The use of a

motorized vehicle to apply chemicals in front country areas may impact some cultural

resources, but guidance by the park archeologist would help to avoid any negative

impacts. It is anticipated that troublesome invasive exotics plants would decrease as

the full range of IPM techniques are implemented. Less mechanical control would be

required, which would ameliorate cumulative impacts to cultural resources. As native

vegetation is restored, and as mechanical control activities are reduced, cultural

resource sites would stabilize

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to cultural resources whose

conservation is: 1) necessary to fulfill specific purposes identified in the enabling

legislation of RMNP; 2) key to the natural or cultural integrity of the Park; or 3)

identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.

Human Environment

Methodology and Intensity Thresholds

Analyses of the potential intensity of impacts from the effects of control techniques on

the human environment were derived from park files and literature cited in this plan.

The impact on the ability of the visitor to experience a full range of park resources was

analyzed by examining resources mentioned in the park significance statement. The
90

thresholds of change for the intensity of impacts to the human environment are defined

as follows:

• No impact ñ There is no discernable impact

• Negligible ñ The impact would be so small that it would not be of any measurable

or perceptible consequence.

• Minor ñ The impact is slight but would be small and localized and of little

consequence.

• Moderate ñ The impact is readily apparent, would be measurable and

consequential, and/or will affect many visitors.

• Major ñ The impact is severely adverse or exceptionally beneficial. The change

would be measurable with possible permanent consequences, and/or will affect the

majority of park visitors.

• Impairment ñ A major, adverse impact to a resource or value whose conservation

is (1) necessary to fulfill specific purposes identified in the enabling legislation or

proclamation of RMNP; (2) key to the natural or cultural integrity of the park; or (3)

identified as a goal in the park’s general management plan or other relevant NPS

planning documents.

Socioeconomics

RMNP is one of the top tourist attractions in Colorado. RMNP contributes about $320

million to the Colorado economy each year in direct, indirect and value added

economic inputs (2002 Money Generation Model). About 3,800 jobs have been created

in neighboring counties as a direct or indirect result of the existence of RMNP. Visitors

come to RMNP expecting to see a pristine environment with clear vistas and abundant

wildlife. 

Today, invasive exotic plants infest approximately 2.6 million acres in the national park

system, reducing the natural diversity of these special places. The NPS mandate is to

preserve and protect natural and cultural resources for the enjoyment of future

generations. It is estimated that about 70 million acres in the United States are infested

with invasive exotic plants, and about 4,600 acres are being newly infested every day.

The cost to the United States to control invasive exotic plants and in lost revenue is

measured in the billions of dollars each year.

RMNP staff estimates that there are about 427 acres of park land infested with 29

invasive exotic herbaceous species. Of this acreage, about 65.25 acres (15%) may be

treated with an synthetic herbicide if Alternative 2 is implemented (see Table 4 on page

28 for the species and number of acres that may be treated, and Table 10 on page 92 for

the estimated cost of herbicide treatment). In addition, an unknown acreage is infested

with six invasive exotic grasses. If left unchecked, these 29 herbaceous invasive exotic

plant species and 6 invasive exotic grasses (35 species total) will cause damage to

resources within the park and would ultimately lead to impairment of park resources.

RMNP has the opportunity to bring these problem plants within manageable levels,

particularly if the full range of IPM techniques can be employed.

RMNP spends a considerable amount of time using mechanical and cultural methods of

control for invasive exotic species. In 2002, park staff and volunteers devoted 2,523

hours to mechanical control of invasive exotic plants (pulling, digging, and using a gas-
91

powered string trimmer). Approximately 142 acres were treated in this manner at a

cost of about $33,300. The average amount of time spent per acre was 17 3⁄4 hours, and

the average cost per acre was about $235.

Synthetic herbicides were last used in the park in 1999. That summer, approximately

six acres were treated with a herbicide in about four hours by one certified applicator

using a tractor with two ten foot booms. The average amount of time spent per acre

was 40 minutes, and the average cost per acre was about $500.

The superintendent of RMNP must weigh the consequences of controlling invasive

exotic plants against the potential impairment that can occur if these plants are not

managed. National Park superintendents are expected to vigorously apply existing

legislative act guidelines, Executive Orders and NPS national regulatory standards and

policies in regards to managing invasive exotic plants. Park superintendents are also

expected to determine if invasive exotic plants and the management of those species are

impairing park resources and values.

If invasive exotic plants are not controlled, there will be an indirect moderate longterm impact on the economic resources of the gateway communities of Estes Park and

Grand Lake. Wildlife viewing is one of the major attractions of the park and the

surrounding communities. If invasive exotic plants, which rarely are of benefit to

wildlife, displace native vegetation, they can displace native wildlife such as elk, deer

and bighorn sheep, which are some of the major wildlife attractions. Loss of wildlife

habitat could cause economic impacts to local economies.

Impacts of Alternative 1 on Socioeconomics

Mechanical Control

Based on 2002 figures, mechanical control requires approximately 18 hours per acre

and costs approximately $235 per acre. Because some species cannot be effectively

controlled except by using the full range of IPM techniques (including the use of

synthetic herbicides), a significant number of acres infested with species such as yellow

toadflax, leafy spurge, and field bindweed, would have to be retreated on an annual

basis. Even if acres were retreated, it is expected that some invasive exotic species

would continue to spread. There would be significant on-going costs associated with

mechanical control with little progress made to reduce the population of some invasive

exotic plants.

Cultural Control

Based on 2002 figures, revegetation costs about $11,000 per acre (including labor and

materials), and prescribed fire costs about $500 per acre. Revegetation can be

particularly effective because once native vegetation has been restored there are few

recurring costs. Vigorously growing healthy native plants can inhibit invasive exotic

plant establishment (McLendon 1996).

There are risks associated with the use of prescribed fire because the treated area could

be susceptible to infestation with invasive exotic plants until the native vegetation

recovers. If a prescribed burn area becomes infested with invasive exotic plants, there

would be the added cost of weed control and possible revegetation.
92

Biocontrol

Biocontrol techniques are relatively inexpensive to implement. The maximum cost for

5,000 flea beetles to be released on leafy spurge is $100.00. Other insects are

substantially more expensive, but in comparison to mechanical and cultural control,

biocontrol is less costly. Biocontrol will not eradicate an invasive exotic plant species,

but it does help to reduce invasive plant populations.

Low Risk Methods

The cost of a hot water machine ranges from about $8,000 to $28,000. The initial cost of

the machine could be shared by other federal, state, county or local agencies. It is

anticipated that using this lower risk method could reduce the amount of time devoted to

digging or hand-pulling dense patches of invasive exotic plants. Over time, it is expected

that the hot water machine could result in a cost-savings as the amount of hand labor

would be reduced.

In 2002, the park experimented with hot water and the results were not encouraging. Most

treated plants did not die and later flowered and set seed. The area was retreated by

mechanical control. Other low risk methods, such as the natural biodegradable products

Burn Out and corn gluten meal, are also being considered for use in the park, but like hot

water, are only considered effective on annuals and perhaps some biennials. Corn and

wheat gluten meal may be effective on Canada thistle (Susan Wolf, personnel

communication). Burn Out and corn gluten meal are also very expensive and cost more

than $500 per acre. Perennial plants like spotted knapweed, yellow toadflax, field

bindweed, dalmatian toadflax, and leafy spurge may not be effectively controlled by hot

water or natural herbicides. Further experiments are proposed.

Impacts of Alternative 2 on Socioeconomics

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

Table 10 provides the estimated cost to treat all known infestations of the 15 invasive

exotic plants identified for synthetic herbicide control. For species with more than one

herbicide identified, the cost would depend on which chemical were applied. Estimated

cost includes the cost of the herbicide and labor. Because some herbicides are more

expensive, the cost per acre can range from $500 to $1000.

Table 10 - Estimated Initial Treatment Cost for Synthetic Herbicide Control

Species

Estimated

Acres Product

Estimated

Initial

Treatment

Cost

Canada Thistle 16.35 Redeem or

2,4-D Amine or

2,4-D Ester or

Transline

$8,000

Cheatgrass <1.00 Roundup $1,000

Common St.

Johnswort

Eradicated Escort *
93

Dalmatian Toadflax 3.50 Plateau+MSO $2,000

Diffuse Knapweed 1.65 Transline or

Tordon $2,000

Field Bindweed <4.75 Paramount or

Rodeo

$5,000

Houndstongue 2.50 Plateau+MSO $2,000

Leafy Spurge 13.75 Plateau+MSO $7,000

Oxeye Daisy 1 Escort $500

Orange Hawkweed <100 plants 2,4-D Amine *

Quack grass 1.00 Roundup $1,000

Smooth Brome 5.00 Roundup $7,000

Spotted knapweed <1.00 Transline or

Tordon or

2,4-D Amine

$1,000

Sulfur Cinquefoil 1.00 Tordon or

2,4-D Ester

$2,000

Yellow Toadflax 12.75 Telar $10,000

Totals 65.25 $49,500

* Orange hawkweed and Common St. Johnswort are below the defined threshold level and do not

warrant chemical control at this time.

Summary of Impacts to Economic Resources from the Implementation of the

Alternatives

Alternative 1 Invasive exotic plant control would be limited to mechanical, cultural,

biological and low risk methods. Implementation of Alternative 1 is expected to be

more costly than Alternative 2. Because there are several exotic plant species that

cannot be effectively controlled through mechanical, cultural, biological or low risk

methods alone, some weed infested areas would need to be retreated on a regular basis,

resulting in higher costs over time with limited minor long-term benefits.

Alternative 2 Using the full range of IPM techniques would result in effective control and

eradication of several invasive exotic species. Once an invasive exotic has been

effectively controlled or eradicated, chemical use can be suspended until the plant reaches

the threshold where chemical use is again warranted (Please refer to Appendix C on page

125). It is anticipated that there will be some years where herbicides would not be used in

the park. We anticipate that there would be a significant reduction in herbicide use within

three years of implementation of Alternative 2, resulting in cost-savings to the park and

taxpayers resulting in a long-term moderate benefit in cost savings.

Visitor Experience

Impacts of Alternative 1 on the Visitor Experience

Mechanical Control

Activities related to mechanical control of invasive exotic plant species (digging,

pulling, and use of gasoline-powered mowers and string trimmers) is expected to have a

short-term localized minor adverse impact on visitor experience. Invasive exotic

plant management activities would occur primarily during the summer months when
94

weeds are actively growing and park visitation is at its highest. Weed control work

would take place only in localized areas of the park and should impact only a small

percentage of park visitors. There would be short-term noise impacts associated with

the use of powered equipment, and short-term visual impacts associated with personnel

working on weed control at various locations within the park.

Cultural Control

Revegetation work is expected to cause short-term localized minor adverse impacts

to visitor experience with long-term minor to moderate benefits. Impacts are

primarily related to the short-term visual intrusion of personnel and equipment at

various restoration areas within the park. Until replanted vegetation fills in the

disturbed area, a significant amount of bare ground or mulch is often visible, which can

be a visual intrusion in an otherwise natural landscape. Restoration areas are usually

closed to visitors by fencing and signing until the area is considered recovered. In

some limited situations, this could be for up to 20 years. Closures would not affect an

established trail or road unless such closure had been addressed in a NEPA document,

such as an Environmental Assessment (EA). No roads or trails would be closed for

revegetation because of the adoption of one of the alternatives in this Invasive Exotic

Plant Management Plan and EA.

When prescribed fire is used for exotic plant management, it is expected that there

would be a short-term minor adverse impact on visitor experience. Immediately

following the burn there would be blackened ground and vegetation, and little

groundcover. Some visitors would perceive this as a negative visual impact. Usually

native grasses and forbs would return within one year. Smoke may impede a scenic

vista for a short time, but smoke dispersal is considered in any burn plan. Prescribed

burns are not conducted if conditions are not favorable for smoke dispersion.

Biological Control

Biological control should have no impact on visitor experience.

Low Risk Methods

The use of a hot water machine would have a short-term localized minor adverse

impact on visitor experience. There would be short-term noise and visual impacts

while the equipment is being used. Following the application of hot water, visitors

would see wilted exotic plants, and ultimately brown (dead) exotic plants in an

otherwise natural appearing landscape. Over the long-term, the exotic plants would be

replaced with healthy native vegetation. Visitors would also see wilted plants when

natural biodegrable chemicals are used. Notification signs would remain in place at all

areas treated with natural chemicals for up to 120 days after the chemical was applied.

Impacts of Alternative 2 on the Visitor Experience

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

Synthetic herbicide control is expected to have a short-term localized minor adverse

impact with a long-term moderate benefit on visitor experience. Chemical control

activities (use of backpack sprayers, use of a truck or ATV with a boom sprayer) would
95

create short-term noise impacts and visual impacts. Chemical control work would take

place only in localized areas of the park and would impact only a small percentage of

park visitors.

By April 30 of each year, park personnel would identify locations in the park where

herbicide application is warranted. Herbicide treatment would not be done outside of

the identified locations. Based on this information, RMNP would identify trail

segments, trailheads, picnic areas, parking lots and campsites that are located within or

adjacent to the planned treatment areas. RMNP would also identify all campgrounds in

the park that would remain chemical free for that year. This information would be

made available to the public via the RMNP website and other print media.

To the extent possible, RMNP would not conduct chemical application near trails,

trailheads, picnic areas, parking lots and campsites between Memorial Day and Labor

Day. Areas to be treated with a herbicide would be identified with yellow signs and

would be closed to the public during chemical application. Hard surfaced areas (parking

lots, trails, trailheads, picnic areas and campsites) adjacent to treated areas would be

reopened within 4 to 48 hours, in accordance with the reentry time stated on the chemical

manufacturer’s label. Notification signs would remain in place at all treated areas for up

to 120 days after the chemical was applied.

Park visitors, chemically sensitive people, park neighbors and owners of private

inholdings near proposed treatment areas would be notified. The notification would

identify where herbicides are to be used, when they would be applied and how long the

area would remain closed (please refer to the mitigation measures beginning on page 104).

Some people may avoid the park entirely, or may avoid areas where chemicals have been

applied even after an area is reopened to the public.

Summary of Impacts to Visitor Experience from the Implementation of the

Alternatives

Alternative 1 Mechanical, cultural, biological and low risk control methods are expected

to result in short-term localized minor adverse impacts on visitor experience. These

impacts are primarily related to noise and the visual intrusion of equipment and personnel.

Without synthetic herbicide control, it is anticipated that some invasive exotic plants

would continue to spread within the park, most notably leafy spurge, yellow toadflax, field

bindweed and possibly Canada thistle. Over time these exotic species could displace

native plant species, affecting the abundance and distribution of wildlife. Ultimately,

these landscape changes could have a long-term moderate adverse effect on visitor

experience.

Alternative 2 This alternative allows the park to implement the full range of IPM

techniques for invasive exotic plant control, including the use of synthetic herbicides.

Chemical use would create short-term localized minor adverse impacts for park

visitors. During and after chemical application, limited areas of the park would be

closed to visitors, which would inconvenience some visitors. People with Multiple

Chemical Sensitivity (MCS) may choose to avoid the park entirely for a period of time.
96

Through the judicious use of herbicides, invasive exotic plant species can be effectively

managed and displacement of native plant species and wildlife can be avoided. Over

the long-term this would be a moderate benefit to visitor experience.

Human Health and Safety

Impacts of Alternative 1 on Human Health and Safety

Mechanical Control

Mowing, digging or using a gasoline-powered string trimmer on invasive exotic plants is

expected to have a minor impact on human health and safety.

Volunteers or park employees who engage in mechanical control activities face risks that

are similar to those encountered when people are involved in strenuous outdoor activities

during the summer months. Risks include dehydration, fatigue, heat exhaustion, or heat

stroke. Falls or other accidents are also possible. Other potential hazards related to

manual operations include eye irritation or damage from flying debris, and bodily injuries

from hand tools such as pulaskis, shovels, or hoes.

There are other hazards associated with digging or hand-pulling invasive exotic plants.

Canada thistle has sharp spines that can penetrate the skin. Some of the knapweeds and

leafy spurge produce irritants that may cause sneezing, blisters, inflammation, and

dermatitis. Workers may be at risk from biting or stinging insects. For example, bees

frequent thistle flower heads, so workers may be stung.

Cultural Control

Revegetation work within the park is expected to have a minor impact on human health

and safety. Volunteers or park employees who engage in revegetation activities face risks

that are similar to those mentioned above.

Prescribed fire activities within the park are expected to have a short-term minor impact

on public health and safety, related to smoke. Smoke produced from prescribed fires can

be an eye irritant and can cause respiratory problems. Prescribed fire activities would

occur in a limited area within the park, and park visitors would be able to avoid these

areas. Limited use of prescribed fire to control invasive exotic plants is possible near the

park boundary, so there may be minor impacts to nearby residents related to smoke.

For a period of one year, prescribed fires would be excluded from areas where herbicides

have been applied, so there would be no impact related to chemical exposure. A

prescribed fire may be conducted before a chemical is applied and chemicals may be used

one to two months after a prescribed fire. Smoke from burning some invasive exotic

plants like leafy spurge or knapweed could irritate fire fighters. Fire fighters would be

encouraged to always stay upwind to avoid inhaling smoke.

Personnel who engage in prescribed fire activities face risks that are similar to those

encountered with weed control and revegetation activities. Fire control workers may also

be exposed to smoke during a prescribed burn.

Biological Control

Biocontrol techniques are expected to have no impact on human health or safety.
97

Low Risk Method

Applying hot water to invasive exotic plants would have a minor impact on human

health and safety. Park employees applying hot water to vegetation may be at risk of

increased fatigue, heat exhaustion or heat stroke. Falls or other accidents may occur.

Other potential hazards related to hot water operations include burns from scalding

water. Workers applying the hot water would use Personal Protective Equipment

(PPE).

The foam that is applied with the hot water machine is made from plant sugars and is

not harmful to the environment or to human health. The public can enter an area during

and immediately after treatment as long as they are not in the immediate vicinity of the

hot water machine, hose, or spray nozzle.

Park employees applying natural chemicals may be at risk because the products with

acetic acid have a low pH that could cause burns to exposed skin. The fumes, even

though not caustic, may be irritating. Workers applying any natural chemical would

use PPE as specified on the label or Material Safety Data Sheets (MSDS) including

wrap around goggles.

The park will use the same public notification process for natural and synthetic

herbicides. By April 30 of each year, park personnel will identify locations in the park

where natural herbicide application is warranted. Natural herbicide treatment will not

be done outside of the identified locations. Areas to be treated with a natural herbicide

would be closed to the public during chemical application and for at least 4 to 48 hours

after the natural chemical was applied, based on the re-entry time interval stated on the

product label and MSDS sheets. Park visitors, chemically sensitive people, and park

neighbors and owners of private inholdings near proposed treatment areas would be

notified. The notification will identify where the natural herbicides are to be used, when

they will be applied, and how long the area will remain closed (please refer to the

mitigation measures beginning on page 104). With implementation of the mitigating

measures, there should be no impact from the application of natural herbicides on the

health and safety of park visitors, private inholders, or park neighbors.

Impacts of Alternative 2 on Human Health and Safety

The environmental consequences of using mechanical, cultural, biological and low risk

IPM methods are the same as Alternative 1.

Synthetic Herbicide Control

Evaluations of potential human health effects due to herbicide exposure are based on

results of toxicity tests in laboratory animals or studies conducted on human health

from chemical exposures. Table 11 on page 98 summarizes the potential effects on

human health of the nine (9) herbicides proposed for use in RMNP. All of the

herbicides, except for Plateau, were evaluated using the following sources:

• Risk Assessment for Herbicide Use (USDA-USFS, 1992)

• The Nature Conservancy 2001 Weed Control Methods Handbook

• Numerous web sites (please see Appendix K on page 144).

The 1992 USDA-USFS Risk Assessment quantified general systemic and reproductive

human health risks for a given herbicide by dividing the dose found to produce no ill
98

effects in laboratory animal studies by the exposure a person might get from applying

herbicides or from being near an application site. Human cancer risk was calculated for

those herbicides that caused tumor growth in laboratory animal studies by multiplying a

person’s estimated lifetime dose of the herbicide by a cancer probability value (cancer

potency) calculated from the animal tumor data. The risk assessment included a

qualitative analysis of the risk of heritable mutation and synergistic effects. Those

risks, summarized below, are based on conservative, worst-case assumptions, including

comparing short-term exposure to long-term safety levels. There can be an indirect

effect on human health from herbicide use through improper application, mixing, or

contamination of a water source.

Table 11 - Impact of Synthetic Herbicides on Human Health

Herbicide/Active

Ingredient Impacts of the Herbicide on Human Health Effects

Redeem R&P

(Triclopyr &

clopyralid)

It is not known to be carcinogenic to animals. No reported effects of acute

toxicity. The exposure levels a person could receive from routine operations,

are below levels shown to cause harmful effects in laboratory studies.

Surfactants and emulsifiers used with Redeem are generally low in toxicity.

Triclopyr is classified as a Group D chemical (not classifiable as to human

carcinogenicity). The most common breakdown product of triclopyr in

mammals is 3,5,6-tricholor-2-pyridinol (TCP). The most significant health

hazard identified for TCP is that it may be hazardous to children.

2,4-D Amine, 2,4-D

Ester

Nervous system damage has resulted from absorption of 2,4-D through the

skin. Nerve damage may be irreversible. Prolonged inhalation may cause

dizziness, burning in the chest or coughing. Ingestion of large quantities of

2,4-D formulations has led to death within 1 to 2 days of poisoning. Longterm exposure of 2,4-D formulations has been reported to cause liver, kidney,

digestive, muscular, or nervous system damage. Some commerciallyformulated 2,4-D products such as 2,4-D Amine have LC50s which are much

higher than the 2,4-D acid. This indicates that Amine may have considerable

less acute toxicity than the acid form. Mammals have a moderate sensitivity

to 2,4-D exposure. It may cause eye damage and skin irritation for humans

that come into contact with 2,4-D formulations. Some pesticide applicators

who spray 2,4-D and other herbicides have altered levels of male sex

hormones in their blood and a heightened rate of non-Hodgkin’s lymphoma.

2,4-D formulations were not mutagenic in most studies. LC50 for birds

ranged from 472 to >2000 mg/kg and for mammals 639 to >5000 mg/kg.

2,4-D can be absorbed through the skin or through the lungs if inhaled.

Applicators of 2,4-D, particularly those using back-pack sprayers, are at

greatest risk of exposure.

Transline

(Clopyralid)

It is not classified as a carcinogen, teratogen, mutagen, or reproductive

inhibitor. No reports of acute poisoning in humans have been found.

Clopyralid can cause severe eye damage including permanent loss of vision,

so protective wrap around goggles are mandatory for applicators. Expected

exposure levels are below the lowest level that should cause harmful effects.

Prolonged exposure may irritate the skin. Repeated exposures to high

amounts may cause liver and kidney damage. No hazardous contaminants

have been identified in Transline.
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Herbicide/Active

Ingredient Impacts of the Herbicide on Human Health Effects

Roundup & Rodeo

(Glyphosate)

Roundup and Rodeo are not considered carcinogenic to humans and are often

portrayed as toxicologically benign. However, two new studies indicate that

Glyphosate is a hormone-disrupter and is associated with birth defects in

humans. Other studies conducted on rats and mice indicate higher levels of

toxicity. A Swedish study of hairy cell leukemia (HCE), a form of nonHodgkin’s lymphoma, found that people who were occupationally exposed to

glyphosate herbicides had a threefold higher risk of HCE. Roundup and

Rodeo cause genetic damage in laboratory animals and in human blood cells.

Long-term glyphosate exposure has been linked to reproductive problems in

humans. Most reported incidents of impacts to humans have involved skin or

eye irritation while mixing and loading. Swallowing Roundup or Rodeo

causes mouth and throat irritation, pain in the abdomen, vomiting, low blood

pressure, reduced urine output, and in some cases, death. These effects have

only occurred when the concentrate was accidentally or intentionally

swallowed. The amount swallowed averaged about 1⁄2 cup. The exposure

levels a person could receive from Roundup or Rodeo in RMNP as a result of

application operations would be below levels shown to cause harmful effects

in laboratory studies.

Plateau (Imazapic) Plateau is not mutagenic, carcinogenic or teratogenic and would not be

expected to have any adverse effect on humans. Plateau is considered of low

toxicity to mammals. It does not have the potential to “mimic” estrogen, nor

can it be considered an endocrine disrupter. It is considered nontoxic to

mammals through physical exposure or ingestion. If ingested, Plateau is

rapidly excreted in the urine and feces and does not bioaccumulate. There are

no human health effects of the inert ingredients in Plateau.

Tordon (Picloram) The preponderance of data shows Picloram to be non-mutagenic in ‘In vitro’

(test tube) tests and in animal test systems. More recent studies that followed

the EPA decision to allow re-registration of picloram show some evidence of

mutagenicity. The potential for causing tumors (oncogenicity) has not been

determined but more studies are ongoing. EPA has found that there is some

added cancer risk for applicators, based on the contamination of picloram

with Hexcholrobenzene (HCB) and the structural similarity to di-(2-

ethylhexyl)-phthalate or DEHP. In contrast to picloram, HCB is absorbed by

the body and does bioaccumulate. A few cases of eye and skin irritation have

been reported in workers. There are no reported cases of long-term health

effects in humans. The exposure levels a person could receive from these

sources, resulting from routine operations, are below levels shown to cause

harmful effects in laboratory studies. No serious health effects in humans

have been verified. Picloram, when commercially produced, is contaminated

with trace amounts of hexachlorobenzene (HCB). Although HCB may cause

cancer in humans, the EPA considers the risk from the small amount of HCB

present in picloram to be small. Picloram is not fat soluble, does not

accumulate in the human body, is not modified by metabolism to more

harmful compounds, and is excreted unchanged from the human body within

24 to 48 hours. EPA has established a 12 hour restricted reentry interval for

applicators using picloram, and this restriction would also apply to visitors.
100

Herbicide/Active

Ingredient Impacts of the Herbicide on Human Health Effects

Paramount

(Quinclorac)

It is not classified as a carcinogen, teratogen, mutagen, or reproductive

inhibitor. It is considered practically nontoxic to avian species, fish, aquatic

invertebrates, and honeybees. Avian and aquatic studies show no significant

effects. It does not bioaccumulate in animals. It is not considered an

estrogen disrupter and is rapidly excreted in urine.

Escort (Metsulfuron

methyl)

No reports of acute poisoning in humans have been found. No reports of

chronic poisoning in humans have been found. Expected exposure levels are

below the lowest level that would cause harmful effects. Exposure to Escort

may cause skin and eye irritation. No hazardous contaminants have been

identified in Escort. It is practically nontoxic to birds and mammals and is

not considered a carcinogen, mutagen, teratogen or reproductive inhibitor.

Telar

(Chlorsulfuron)

No reports of poisoning in humans were found. There are no reported cases

of long-term health effects in humans. The exposure levels a person could

receive from Telar resulting from routine operations, are below levels shown

to cause harmful effects in laboratory studies. Telar may cause irritation to

the skin, eyes, nose and throat. It is not known to be carcinogenic to animals.

The Human Toxicity Potential (HTP) is an indicator of the danger posed by a

chemical’s release to air or surface water. It was developed to compare emissions in

life-cycle assessment (LCA) and public emissions inventories, such as the U.S. Toxic

Release Inventory (TRI). HTP contains two elements:

1. The toxicity of the chemical. This is represented by the unit risk factor (for

carcinogens) or the safe dose (RFD) for non-carcinogenic effects.

2. The potential dose. This is represented by the intake of the pollutant by an

individual living in a certain model environment (Hertwich et al. 2001, Hertwick et

al. 2000).

HTP data are addressed in the plan and are available at the following Internet address:

http://design.ntnu.no/ansatte/hertwich/HTP_ETC.html

Chemical effects on the public

Members of the public, including individuals with Multiple Chemical Sensitivity

(MCS), may be exposed to herbicide via dermal, respiratory, and dietary routes (e.g.

contact with vegetation at a recently treated site, breathing herbicide vapors in or near

recently treated areas, touching or eating berries with residues)

Toxicology – With the implementation of the mitigation measures found on page 104,

it is unlikely that the general public would receive doses above “no observed effect”

levels.

Cancer and Mutation – Human cancer risks from exposure appear to be negligible from

the amount of herbicides proposed. However, scientific uncertainty over cancer risks

remain. Known risks to the general public are thought to be too low to detect in

epidemiology studies (USDA-USFS 1996).

Bioaccumulation – Given the herbicides and amounts proposed for use in RMNP, the

potential for bioaccumulation or biomagnification appears to be negligible. Humans
101

and animals high in the food chain that occur in the park (humans, eagles, coyotes,

mountain lions, peregrine falcons) are not expected to receive concentrated doses of the

chemicals by feeding on contaminated plants or animals. The herbicides are watersoluble and are excreted rapidly (USDA-USFS 1996).

Multiple Chemical Sensitive Population

There are individuals who are extremely sensitive to pesticides and other chemicals.

Individual susceptibility to the toxic effects of pesticides is variable and unpredictable.

The normal margin of safety is generally considered by toxicologists to be sufficient to

ensure that most people would experience no toxic effects from pesticides applied in

accordance with label provisions. However, MCS individuals may experience effects

from extremely small amounts of pesticides. For this reason, RMNP will notify all

persons listed in the Colorado Registry of Pesticide Sensitive Persons at least annually

regarding planned applications of natural and synthetic chemicals for weed control.

Chemical Effects on Employees

Workers applying herbicides may be exposed to chemicals via dermal, respiratory, and

dietary routes (e.g. contact with vegetation at a recently treated site, breathing herbicide

spray particles, breathing herbicide vapors at a recently treated site, touching or eating

berries with residues).

Toxicology – Routine-typical exposures are those likely to occur in the vast majority of

applications. Routine-typical exposures are based on average conditions such as

average application rate, average number of acres treated, average buffer distances, and

average doses seen in field-based exposure guides (USDA 1992). Barring accidents, it

is unlikely workers would receive doses above the “No observed effect” level.

Exposure would exceed “acceptable daily intake” only if they fail to use Personal

Protective Equipment (PPE).

During routine operations, workers may be dermally exposed to an herbicide if the

herbicide concentrate, mixture, or drifting spray droplets contact their skin; or if the

workers contact sprayed vegetation. Respiratory exposure may result from inhaling airborne spray droplets if workers fail to wear protective masks or respirators. Field

studies of workers have demonstrated that inhalation exposure represents only a small

part of the total exposure. Dermal exposure can be up to 50 times greater than

inhalation exposure.

Research shows that PPE such as long-sleeved shirts, coveralls, rubber gloves, and hats

can substantially reduce dermal exposure. Inhalation of herbicides is reduced by using

protective breathing devices.

Cancer and Mutation –Human cancer risks from exposure to the herbicides we propose

to use are negligible. However, there is scientific uncertainty over cancer risks. The

lifetime risk to workers (assuming application for 30 days each year for 30 years) range

from 0.5 to 50 cancer occurrences in a population of one million applicators.

Bioaccumulation – Given the herbicides and amounts proposed for use in RMNP, the

potential for bioaccumulation or biomagnification appears to be negligible. The

number of acres proposed to be treated is also low, which will minimize exposure risk.

Humans and nimals high in the food chain (humans, eagles, coyotes, mountain lions)
102

are not expected to receive concentrated doses of these chemicals by feeding on

contaminated plants or animals. The herbicides are water-soluble, generally not lipid

soluble, and are excreted rapidly (USDA-USFS 1996).

Summary of Impacts on Human Health and Safety from the Implementation of the

Alternatives

Alternative 1 The invasive exotic plant control techniques that would be employed for

Alternative 1 are expected to create minor impacts to park visitors, nearby private

inholders or nearby residents. The only impact of significance would be from smoke

generated during prescribed burning activities used for exotic plant management. Park

employees and volunteers would be exposed to risks inherent with strenuous outdoor

activities during the summer months, and the hazards associated with the use of hand

tools, gasoline powered equipment, natural chemicals and a hot water machine. Some

employees may be sensitive to toxins found in knapweeds and leafy spurge, and PPE gear

such as long-sleeved shirts and gloves are recommended. Fire fighters are encouraged to

avoid inhaling smoke when conducting prescribed fires where leafy spurge and knapweed

exists.

Alternative 2 If this alternative is selected the same risks associated with Alternative 1

would also be present for Alternative 2. In addition, visitors, private inholders, nearby

residents, park employees and volunteers would be exposed to the risks associated with

the use of synthetic herbicides. With the implementation of the mitigation measures found

on page 104, the potential impact of herbicide use on human health is expected to be

negligible.

Cumulative Impacts

With implementation of the Mitigation Measures (please refer to page 104), which

include employee safety measures and adequate notification of the public, there would

be no cumulative impact to human health and safety.

Conclusion for Alternative 1 or 2

Because there would be no major, adverse impacts to the Human Environment whose

conservation is: 1) necessary to fulfill specific purposes identified in the enabling

legislation of RMNP; 2) key to the natural or cultural integrity of the Park; or 3)

identified as a goal in the Master Plan (1976) or other relevant NPS planning

documents, there would be no impairment of the Park’s resources or values if either

Alternative 1 or 2 is selected.
103

CHAPTER 6 SHORT-TERM USES VERSUS LONG-TERM

PRODUCTIVITY

The implementation of either Alternative 1 or Alternative 2 would result in

environmental impacts, but these impacts would be small in comparison with the

benefits derived from controlling and eradicating invasive exotic plants.

Alternative 1 allows for the use of mechanical, cultural, biocontrol and low risk

methods including natural chemical treatments, but not synthetic chemicals.

Biological treatments can have some long-term benefit to natural resources, but

biocontrol is limited to a few invasive exotic species and could have some long-term

negative impacts. Because some invasive exotic plants are expected to persist with the

implementation of Alternative 1 (most notably leafy spurge, yellow toadflax, and field

bindweed) this alternative would cause some long-term negative impacts on the

productivity of habitats within the park.

Alternative 2 would have the least impacts on the long-term productivity of resources

by providing the most effective control of invasive exotic plants through the use of the

full range of IPM techniques. However, this alternative would result in some shortterm impacts primarily related to the application of synthetic herbicides. Herbicides

would have a negative, short-term impact on some natural resources. It is anticipated

that the use of herbicides would taper off substantially over time and the park may

become herbicide free for one or more years at a time.
104

CHAPTER 7 MITIGATION MEASURES

Mitigation Measures Common to Alternatives 1 and 2

1. Conduct on-site field surveys prior to treatment to determine the presence and

proximity of resources that may be at risk from invasive exotic plant treatments,

including aquatic resources, T&E and rare species, proposed or designated

wilderness and cultural resources.

2. Mechanical and cultural treatments that involve any kind of soil disturbance will be

cleared with the park’s archeologist to ensure work is not occurring in an

archeological site. If soil disturbance will occur in an identified archeological site,

a qualified archeologist or para-archeologist must be on site while work is being

performed.

3. Protection of cultural resources will be included in training programs for the exotic

plant seasonal work crew.

4. Provide for minimum feasible soil disturbance in or around wetlands. Keep

vehicles out of streams, and swales. Do not use vehicles within 100 feet of a stream

if in a wetland.

5. Limit the use of hot water or natural chemicals to only dense patches of invasive

exotic plants to minimize impacts to native vegetation, or use a wick or wand

applicator for spot treatment. Any natural biodegradable chemical will require

either an EPA registration number or a Colorado State permit before it can be used.

Revegetating denuded areas after treatment may be needed, particularly on drier

steeper slopes.

6. Limit control techniques to those that do not adversely affect native plant and

wildlife species.

7. Conduct on site reviews with NPS or USFWS wildlife biologist in riparian areas

infested with invasive exotic plants that are adjacent to greenback cutthroat trout,

Colorado River cutthroat trout, and in boreal toad habitat during peak spawning and

reproduction periods.

8. Avoid work near active birds of prey nests during the breeding season from March

through July. Consult with the park’s wildlife technician, GIS Specialist, or Natural

Resources Specialist for known raptor nest locations.

9. Include job hazard analysis for invasive exotic plant work. Ensure all employees

and volunteers are given proper personnel protective equipment (PPE) and safety

instructions for all treatment methods.

10. Do not remove all organic matter - unless site-specific soil types warrant complete

removal - when pulling, cutting, or mowing exotic plants.

11. Maintain or add organic matter or soil inoculate to areas disturbed by mechanical

methods and to sites denuded by removal of dense invasive exotic plant

infestations. Revegetate heavily disturbed sites or denuded areas with native

vegetation in accordance with RMNP’s Vegetation Restoration Plan (McLendon
105

and Redente 1994), the park’s genetic guidelines, Go No Go checklist for active

verses passive restoration and Class I, II, III area descriptions.

12. Use the “Minimum Requirement Decision Guide,” provided by the RMNP

Wilderness Coordinator, for invasive exotic plant work in recommended or

designated wilderness.

13. Consult RMNP plant databases to identify known locations of rare plants. If

surveys are warranted, conduct them when plants are expected to be flowering or

have aerial stems or catkins to determine presence or absence of sensitive species in

the project area prior to treatment.

14. Ensure that all invasive exotic plant inventory personnel and crews removing plants

are able to identify all exotic plants and at least one crew member is able to identify

rare native species. For example, where native thistles occur with exotic thistles, it

is imperative the native thistles are not inadvertently destroyed.

15. Avoid ground disturbance that could lead to erosion in the alpine tundra. Drier

steeper sites in alpine tundra disturbed by removing invasive exotic plants may need

to be revegetated with local genotypic plants.

16. Avoid treatment in sensitive wildlife habitat during lambing, calving or denning

periods. This generally occurs between May 1 to mid-June for low elevation areas

and from May 1 to August 31 for high elevation areas.

17. When transporting biological control insects with host plant material, use containers

that prevent release of the insects prematurely and release of seed from the invasive

exotic plant.

18. Identify sensitive plant species that could be affected by selected biological control

agents, survey proposed project sites for those species, and develop project-specific

measures to protect them. Biocontrol insects or pathogens may not be used if native

plants will be adversely affected

Mitigation Measures Specific to Alternative 2

1. The Communication Plan (please see Appendix F on page 135) will be

implemented.

2. Use only water as a carrier for herbicides.

3. Use the Relative Aquifer Vulnerability Evaluation (RAVE) scoring system to

evaluate pesticide selection for on-site groundwater contamination potential.

RAVE is designed only as a guidance system and does not replace the need for safe

and judicious pesticide application required in all situations.

4. Use only aquatic-labeled herbicide formulations for spraying in riparian

ecosystems, wetlands, or water influence zones or conduct spot treatments with a

wand or wick applicator based on the RAVE scoring system, herbicide labels, and

recommendations from the NPS Intermountain Region IPM Coordinator. Water

treatment zones are defined as the land next to water bodies where vegetation plays

a major role in sustaining long-term integrity of aquatic systems. The water

influence zone varys, but a recommended buffer zone is 100 feet from the top of

each stream bank, or a distance equal to the mean height of mature dominant late-
106

seral upland vegetation, whichever is greater. This measure also applies to areas

along roads, trails, and utility corridors within 100-feet of stream crossings.

5. Use the hot water treatment or natural chemicals in sensitive riparian or wetland

areas to the degree possible. Synthetic herbicides will only be used as a last resort

if other techniques are not successful and invasive exotic plants exceed established

threshold levels. If synthetic herbicide use is warranted in a riparian or wetland

area, use only hand-held wand or wick applicators. Use spot treatment strategy if

possible. This measure also applies to areas along roads, trails, and utility corridors

within 100-feet of stream crossings.

6. Determine buffer zones where herbicide spraying will be prohibited. Identify

buffer zones with pin flags before spraying begins to avoid open water, habitat for

rare plants and animals, desired vegetation such as trees, and private inholdings.

Buffers will be a minimum of 100-feet, and shall be larger where required by

applicable law, regulation or policy. Wand or wick application may be approved

within the buffer zone based on the herbicides label, RAVE scoring, and approval

by the NPS Intermountain Region IPM Coordinator.

7. Select application methods, equipment, and rates that minimize potential for drift

and off-target impacts while meeting invasive exotic plant objectives. Use drift

reduction techniques, including appropriate surfactants, coarse, low-pressure spray

of less than 30 psi, appropriate nozzle size and type, and keeping spray nozzles

close to the ground.

8. Ensure contractors are state-licensed commercial applicators and require a qualified

supervisor to oversee herbicide applications, whether conducted by contractor or

NPS personnel.

9. All use of herbicides with an EPA registraton number must be approved by the NPS

Pesticide Approval System and designated IPM Coordinator from the Intermountain

Region and the park. Annual Pesticide Use Logs must be filled out in the NPS

approval system.

10. Follow all label instructions and additional instructions provided by the regional

and park IPM Specialists during the NPS Pesticide Approval review.

11. 2,4-D low volatile Ester (LVE) is proposed for orange hawkweed, which is

presently below the threshold for warranting chemicals. 2,4-D Ester (LVE) is also

proposed for Canada thistle in places where the water table is too close to the

surface for the use of Transline or Redeem. 2,4-D Easter (LVE) will not be sprayed

within buffer zones as discussed in mitigating measure #6 or when the RAVE score

is too high. Require RAVE score cards to determine groundwater contamination

potential. If proven effective, the natural chemicals corn or wheat gluten meal

would be preferable over 2,4-D for controlling Canada thistle.

12. When a product such as Roundup or an natural chemical like Burn Out is selected

for use, target invasive exotic plants should be monoculture patches, or the loss of

adjacent non-target plants must be an acceptable aspect of the control project.

Revegetating with native plants will be required unless the patch is small enough

that revegetation would occur naturally from surrounding undisturbed vegetation.
107

The natural herbicide Burn Out or hot water if effective is preferable over the

herbicide Roundup.

13. Monitor weather conditions before and during all herbicide application projects.

Do not apply herbicides when rain appears imminent except for Paramount, which

requires moist soil. In some cases the ground may be watered before or after

Paramount is applied. Do not apply herbicides when temperature, humidity, or

wind conditions specified on the label are exceeded.

14. Use the application rates specified by the manufacturer unless directed otherwise by

a certified applicator or IPM Coordinator.

15. Monitor treated areas to determine effectiveness of the herbicide.

16. Avoid spraying herbicides in known boreal toad, greenback cutthroat and Colorado

River cutthroat habitat.

17. For NPS personnel applying chemicals:

1) Transport only the quantity needed for that day’s work;

2) Transport concentrate to treatment site in original containers in a manner that

will prevent tipping or spilling, and in a compartment that is isolated from food,

clothing, and safety equipment.

18. Ensure that park employees and contractors follow manufacturer’s instructions for

mixing, loading, and disposal of chemicals.

19. Ensure that all chemical applicators, including employees and contractors, inspect

all herbicide application equipment for leaks or other problems before each

application and at intervals during the application day. Test all nozzles, caps or

other fittings for seating at intervals throughout the workday. Set aside any faulty

equipment immediately for repair or replacement.

20. If herbicides are stored in the park they should be kept only in facilities designed

and constructed in accordance with provisions of Title 35, Article 10 of the

Colorado Pesticide Applicator Act; Part 11 of “Rules and Regulations Pertaining to

Administration and Enforcement of the Pesticide Applicator Act.” All pesticide

storage facilities will be constructed with adequate sump capacity to contain

spillage of the entire quantity of pesticide stored.

21. Dispose of all herbicide containers in accordance with State and Federal

requirements. Empty containers thoroughly, rinse them three times and puncture

them to prevent reuse.

22. Assess all herbicide treated areas for revegetation needs. Re-establish vegetation on

bare ground to minimize the opportunity for invasive exotic plant re-establishment,

unless the patch is small enough that natural revegetation will occur from adjacent

undisturbed native vegetation.

23. Ensure that all applicators wear protective clothing, provided by the park as

necessary for either natural or synthetic chemicals. Workers must also wear nonpermeable gloves, hats, and footwear, and any other safety clothing and equipment

recommended or required by the herbicide label and MSDS sheets. During mixing
108

and loading, eye protection and additional protective clothing (e.g. polypropylenecoated overalls or aprons) maybe needed.

24. Personnel applying herbicides should carry additional safety equipment to the work

site including soap, water that is separate from drinking water and clearly labeled as

non-drinking water, eyewash kits, first aid equipment, and extra clothing.

25. Personnel should go through a safety briefing each day prior to beginning herbicide

application.

26. Ensure that MSDS are available at storage facilities, in vehicles, and readily

available to workers.

27. Ensure that all herbicide applicators are aware of (and can identify) threatened,

endangered or rare plants or animals in the area. Flag rare plants with a 100-foot

buffer zone and advise applicators to stay out of the area. Do not use herbicides in

rare plants locations unless warranted under special circumstances and applied in

such a way that will not harm rare plants.

28. By April 30 of each year, park personnel will identify locations in the park where

herbicide application is warranted. Herbicide treatment will not be done outside of

the identified locations. Based on this information, RMNP will identify trail

segments, trailheads, picnic areas, parking lots and campsites that are located within

or adjacent to the planned treatment areas. RMNP will also identify all

campgrounds in the park that will remain chemical free for that year. This

information will be made available to the public via the RMNP website and other

print media.

29. As a safety precaution, prescribed fire shall not be used in any area that has been

treated with an natural or synthetic chemical for a period of one (1) year following

chemical application.
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CHAPTER 8 CONSULTATION AND COORDINATION

The Branch of Planning and Compliance within RMNP’s Division of Resources

Management and Research developed this plan/EA with substantial input from the NPS

Biological Resources Management Division (a WASO office), the solicitor’s office of

the Department of the Interior (Lakewood Colorado), the Intermountain Region

Support Office, and the Intermountain Regional Integrated Pest Management

Coordinator.

Preparers

Jeff Connor, Natural Resources Specialist, RMNP

Larry Gamble, Chief of the Branch of Planning and Compliance, RMNP

Judy Rosen, writer/editor

Summer Schulz, former employee, Biological Resources Management Division, NPS

Gerald McCrea, Intermountain Region Support Office, NPS

List of Agencies and Organizations

The following agencies, universities or environmental organizations were contacted for

information; or assisted in identifying important issues, developing alternatives, or

analyzing impacts; or that will review and comment upon the management plan and

environmental assessment.

Arapaho Roosevelt National Forest

Boulder County Open Space

Boulder, Grand and Larimer Counties weed extension services

City of Boulder Open Space

Colorado Coalition for Alternatives to Pesticides

Colorado Department of Agriculture

Colorado Department of Natural Resources

Colorado State University

Denver Botanical Gardens

Department of the Interior Solicitor’s Office.

Earth Law

Nature Conservancy

Northern Colorado College

Sierra Club

U.S. Fish and Wildlife Service

University of Colorado

University of Nebraska

University of Wyoming

Wyoming Department of Agriculture
110

List of Persons Consulted

The following people were involved in the development of this Plan/EA. They

provided assistance in identifying issues, developing alternatives, or analyzing impacts

related to this plan. They did not necessarily review the entire Plan/EA, nor do they

necessarily agree with the proposed action or all of the material presented.

Paula Anderson, Theodore Roosevelt National Park, NPS

Craig C. Axtell, former Chief of Resources Management and Research, RMNP

Russ Babiak, Fire Management Specialist, RMNP

Bruce Badzik, Golden Gate National Recreation Area, NPS

Beverly Baker, Arapaho Roosevelt National Forest, Boulder District

Vaughn Baker, Superintendent, RMNP

Garth Baxter, Private Consultant

George Beck, Extension Weed Specialist, Colorado State University

Rob Billerbeck, Colorado Department of Natural Resources

Jeff Birk, BASF

Barri Bernier, Biological Science Technician, RMNP

Nehalem Breiter, Biological Science Technician, RMNP

John Bustos, Arapaho Roosevelt National Forest, Fort Collins

Terry Cacek, Biological Resources Management Division, NPS

Mike Carroll, Larimer County Weed District Manager

Greg Cody, former Intermountain Region Support Office, NPS

Karl Cordva, Biologist, RMNP

LeRoy Carlson, Ecological Services, United States Fish and Wildlife Service

Kirk Cunningham, Sierra Club

Ken Czarnowski, Chief of Resources Management and Research, RMNP

Tim Devine, Wilderness Program Specialist, RMNP

Steve Dewey, Utah State Extension Weed Specialist

Laurie, Dieter, Boulder Open Space

Linda Drees, Biological Resources Management Division, NPS

Geneva Chong, USGS-Biological Resources Division, Fort Collins, CO

Jesse Duhnkrack, Fire Management Officer, RMNP

Staff from the Fire Management Office, RMNP

Mark Ferrell, Wyoming Department of Agriculture

Tim Gilpen, private consultant, Boulder, Colorado

Tom Grant, Denver Botanical Gardens

Debra Hecox, Solicitor, Department of the Interior

Pat Hessenflow, Arapaho Roosevelt National Forest, Canyon Lakes District

Mark Hughes, Earthlaw

Lynn and Larry James, Nederland

Pamela Johnson, Botanist, Intermountain Region Support Office, NPS

Randy Jones, former Superintendent, RMNP

Steve King, former employee, RMNP

Cindy Lair former Boulder County Open Space Weed Coordinator.

Eric Lane, Colorado State Weed Coordinator, Colorado Department of Agriculture

Svata Louda, University of Nebraska
111

Jim Moore, Northern Colorado College

David Pillmore, Inventory and Monitoring Database Technician, RMNP

Carlie Ronca, Supervisory Biological Science Technician, RMNP

Tony Schetzsle, Assistant Superintendent, RMNP

Tim Seastedt, University of Colorado

Gunda Starkey and John Ooyen, Nederland

Billy Sumerlin, Grand County Weed District Manager

Barry Sweet, RMNP

Terry Terrell, Research Administrator, RMNP

Ron Thomas, GIS Specialist, RMNP

Chris Turk, Intermountain Region Support Office, NPS

Martin Walter, University of Colorado

Scott Wanek, former Park Ranger, Fall River District, RMNP

Tom Whitson, Extension Weed Specialist, University of Wyoming

Nate Williamson, Fire Effects Specialist, RMNP

Susan Wolf, Colorado Coalition for Alternatives to Pesticides, Allenspark

Kevin Zurfluh, RMNP

William Baker, University of Wyoming

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117

APPENDIX A How the Non-Native Plants were Prioritized

In 1996 there were 1,022 known species of vascular plants in RMNP, of which 102

(10%) were considered exotic. Since 1960, we have monitored, investigated, and

documented the persistent spread of some of these exotic plants in the park.

In 1995-96, Rutledge and McLendon of Colorado State University completed a risk

assessment on the 102 exotic plants. The risk assessment was developed based on a

modified Heibert and Stubbendieck's Handbook for Ranking Exotic Plants (1993). All

known exotic plants of Rocky Mountain National Park at that time were evaluated to

assess their ecological impact. Based upon the evaluation, Rutledge and McLendon

identified 21 species of concern, which are listed below. The table contains

information on the level of ecological impact for each species, and the relative ease of

control. Species were also assigned ‘urgency scores’ ranging from ‘high’ (delay in

action will result in significant effort required for control) to ‘medium’ (delay in action

will result in moderate increase in effort required for control) to ‘low’ (delay in action

will result in little increase in the effort required for control).

Summary of Final Assessment for Exotic Plant Species of Concern

Species Name

Potential

Distribution

(Max. = 15)

Potential

Impact

(Max. = 40)

Current

Impact

(Max. = 50)

Ease of

Control

(Max. = 100)

(0 = Difficult) Urgency

Agropyron repens 6 33 4 40 Med

Bromus inermis 6 33 25 18 Med/High

Bromus tectorum 13 25 17 24 Med

Carduus nutans 11 26 29 25 Med

Centaurea diffusa 11 33 22 26 High

Centaurea maculosa 11 26 22 31 High

Cirsium arvense 11 31 30 8 Med

Cirsium vulgare 11 26 25 34 Med

Chrysanthemum leucanthemem 9 29 8 33 Med

Convolvulus arvensis 6 26 6 22 Med

Dactylis glomerata 6 29 12 34 Med

Euphorbia esula 11 38 42 20 High

Gypsophilia paniculata 9 26 -- 40 Low/Med

Hypericum perforatum 13 38 9 21 Med

Linaria dalmatica 9 31 37 27 Med

Linaria vulgaris 11 27 40 19 High

Lythrum salicaria 11 31 * 31 Med

Melilotus alba 9 24 9 30 Med

Phalaris arundinaceae 9 24 -- 21 Med

Poa pratensis 11 27 23 26 Med

Sonchus uliginosus 9 27 -- 31 Med

* Currently not found in RMNP, but was found adjacent to RMNP. It is currently eradicated

from the Estes Valley.
118

A. Of the 21 species of concern listed in the table, we are proposing to suppress,

contain or eradicate 17 of the species. These are:

1. Baby’s breath (Gypsophilia paniculata)

2. Bull thistle (Cirsium vulgare)

3. Canada thistle (Cirsium arvense)

4. Cheatgrass (Bromus tectorum)

5. Common St. Johnswort (Hypericum perforatum)

6. Dalmatian toadflax (Linaria dalmatica)

7. Diffuse knapweed (Centaurea diffusa)

8. Field bindweed (Convolvulus arvensis)

9. Kentucky bluegrass (Poa pratensis)

10. Leafy spurge (Euphorbia esula)

11. Musk thistle (Carduus nutans)

12. Oxeye daisy (Chrysanthemum leucanthemem)

13. Quackgrass (Agropyron repens)

14. Smooth brome (Bromus inermis)

15. Spotted knapweed (Centaurea maculosa)

16. White sweetclover (Melilotus alba)

17. Yellow toadflax (Linaria vulgaris)

B. Four species listed in the table will not be managed at this time by the park. These

are:

1. Orchard grass (Dactylis glomerata)

2. Purple loosestrife (Lythrum salicaria)

3. Reed canary grass (Phalaris arundinaceae)

4. Swamp sow-thistle (Sonchus uliginosus)

Purple loosestrife does not currently exist in the park. If purple loosestrife is ever

found in the park it will become a high priority plant and will be eradicated. The

other three species, even though they are currently found in the park, will not be

managed due to funding constraints and a lack of research on how best to control

these species without negatively impacting native species. We believe the funds

that are available will be better spent to control the 35 species we have identified.

In addition, further survey and research work is needed to determine appropriate

Integrated Pest Management (IPM) strategies for the four species we will not

control.

C. Since the 1996 risk assessment, eighteen (18) new invasive exotic plants have been

documented in the park that we are proposing to eradicate or control. These are:

1. Bouncingbet (Saponaria officinalis)

2. Common burdock (Arctium minus)

3. Common mullien (Verbascum thapsus)

4. Curly dock (Rumex crispus)

5. Dame’s rocket (Hesperis matronalis)

6. Deptford pink (Dianthus armeria L.)

7. Hoary alyssum (Berteoa incana)

8. Houndstongue (Cynoglossum officianale)
119

9. Orange hawkweed (Hieracium aurantiacum)

10. Red-top grass (Agrostis gigantea)

11. Russian thistle sp. (Salsola collina)

12. Common Russian thistle sp. (Salsola australis)

13. Scentless chamomile (Matricaria perforata)

14. Scotch thistle (Onopordum tauricum)

15. Sheep fescue (Festuca ovina)

16. Sulphur cinquefoil (Potentilla recta)

17. Timothy (Phleum pratense)

18. Yellow sweetclover (Melilotus officianalis)
120

APPENDIX B Proposed Action and Control for 35 Invasive Exotic

Plants

Natural Zone Historic Zone Developed Zone

Babyís breath (Gypsophilia paticulata)

Extent of Population <0.25 acre No known infestation No known infestation

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Bouncingbet (Saponaria officianalis)

Extent of Population No known infestation No known infestation <0.25 acre

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Bull thistle (Cirsium vulgare)

Extent of Population <1.25 acres No known infestation <1.25 acres

Recommended Action Eradicate Eradicate if found Eradicate

Recommended

Control

-Mechanical -Mechanical

Canada thistle (Cirsium arvense)

Extent of Population <100 acres <12.5 acres <25 acres

Recommended Action Contain or suppress Contain or suppress Contain or suppress

Recommended

Control

-Mechanical.

-Chemical within 1⁄2 mi.

of boundary or in other

sensitive locations ~ 2.5

acres.

-Biological if deemed

safe.

-Mechanical.

-Chemical within 1⁄2 mi.

of boundary or in other

sensitive locations ~ 6

acres.

-Biological if deemed

safe.

-Mechanical.

-Chemical within 1⁄2 mi.

of boundary or in other

sensitive locations ~

2.5 acres

-Biological if deemed

safe.

Cheatgrass (Bromus tectorum)

Extent of Population Unknown Unknown ~ 5 acres may be

controlled along Bear

Lake Road and < 1 acre

in the Headquarters

area

Recommended Action Suppress in sensitive

areas

Suppress in sensitive

areas

Suppress in sensitive

areas

Recommended

Control

-Cultural

-Sugar applied at 160

grams per sq. meter

when < 100 square

meters

-Chemical when > 100

sq. meters or when > 10

square meters when

impacting a revegetation

site.

-Cultural

-Sugar applied at 160

grams per sq. meter

when < 100 square

meters at any one

location.

-Chemical when > 100

sq. meters or when >

10 square meters when

impacting a

revegetation site.

-Cultural

-Sugar applied at 160

grams per sq. meter

when <100 square

meters at any one

location.

-Chemical when > than

100 sq. meters or when

> 10 square meters

when impacting a

revegetation site.
121

Natural Zone Historic Zone Developed Zone

Common burdock (Arctium minus)

Extent of Population No known infestation No known infestation <5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

Common mullien (Verbascum thapsus)

Extent of Population 50 acres <2.5 acres <2.5 acres

Recommended Action Contain or suppress Eradicate Eradicate or contain

Recommended

Control

-Mechanical -Mechanical -Mechanical

Common St. Johnswort (Hypericum perforatum)

Extent of Population Currently eradicated Currently eradicated Currently eradicated

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Biological

-Mechanical

-Chemical

-Biological

-Mechanical

-Chemical

-Biological

Curly dock (Rumex crispis)

Extent of Population ~ 2.5 acres No known infestation No known infestation

Recommended Action Eradicate or contain Eradicate or contain Eradicate or contain

Recommended

Control

-Mechanical -mechanical -Mechanical

Dalmatian toadflax (Linaria dalmatica)

Extent of Population <7.5 acres <2.5 acres <5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical

-Mechanical

-Chemical

Dames rocket (Hesperis matronalis)

Extent of Population No known infestation No known infestation Currently eradicated

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Deptford pink (Dianthus armeria L.)

Extent of Population <2.5 acres No known infestation No known infestation

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Diffuse Knapweed (Centaurea diffusa)

Extent of Population No known infestation No known infestation <2.5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical

-Mechanical

-Chemical

Field bindweed (Convolulus arvensis)

Extent of Population <3.1 acres No known infestation <1.7 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical
122

Natural Zone Historic Zone Developed Zone

Hoary alyssum (Berteoa incana)

Extent of Population No known infestation <2.5 acres <2.5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Houndstongue (Cynoglossum officianale)

Extent of Population 2.5 acres No known infestation 2.5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical

Kentucky bluegrass (Poa pratensis)

Extent of Population Unknown Unknown Unknown

Recommended Action Contain or suppress Contain or suppress Contain

Recommended

Control

-Fire

-Cultural

-Fire

-Cultural

-Fire

-Cultural

Leafy Spurge (Euphorbia esula)

Extent of Population 4 acres 5 acres 2.5 acres

Recommended Action Contain and then

Eradicate

Contain and then

Eradicate

Contain and then

Eradicate

Recommended

Control

-Chemical

-Biological

-Mechanical such as

digging when a patch is

< 10 sq. meters

-Chemical

-Biological

-Mechanical such as

digging when a patch is

< 10 sq. meters

-Chemical

-Biological

-Mechanical such as

digging when a patch is

<10 sq. meters

Musk thistle (Carduus nutans)

Extent of Population <38 acres <2.5 acres <2.5 acres

Recommended Action Contain and then

eradicate

Eradicate Eradicate

Recommended

Control

-Mechanical

-Biological

-Mechanical

-Biological

-Mechanical

-Biological

Orange Hawkweed (Hieracium aurantiacum)

Extent of Population 110 sq. ft. No known infestation No known infestation

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

- Mechanical

- Chemical

Oxeye daisy (Chrysanthemum leucanthemum)

Extent of Population <0.25 acre No known infestation <0.25 acre

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical

Quack grass (Agropyron repens)

Extent of Population Unknown Unknown <2.5 acres

Recommended Action Contain and then

eradicate

Eradicate Eradicate

Recommended

Control

-Fire

-Chemical

-Fire

-Chemical

-Fire

-Chemical
123

Natural Zone Historic Zone Developed Zone

Red-top Grass (Agrostis gigantea)

Extent of Population Unknown Unknown Unknown

Recommended Action Contain or suppress Contain or suppress Contain or suppress

Recommended

Control

-Cultural

-Limited mechanical

-Cultural

-Limited mechanical

-Cultural

-Limited mechanical

Russian thistle (Salsola collina)

Extent of Population No known infestation 2.5 acres 2.5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

Common Russian thistle (Salsola australis)

Extent of Population No known infestation 2.5 acres 2.5 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

-Cultural

-Mechanical

-Sugar applied at 160

grams per square meter

Scentless chamomile (Matricaria perforata)

Extent of Population 2.5 acres No known infestation 1.25 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Scotch thistle (Onopordum tauricum)

Extent of Population Presently eradicated No known infestation No known infestation

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical -Mechanical -Mechanical

Sheep Fescue (Festuca ovina)

Extent of Population 2.5 acres No known infestation 2.5 acres

Recommended Action Contain and then

eradicate

Contain or suppress Contain or suppress

Recommended

Control

-Fire

-Mechanical

-Fire

-Mechanical

Smooth Brome (Bromus inermis)

Extent of Population Unknown 7.5 acres 12.5 acres

Recommended Action Contain and suppress in

sensitive areas

Contain and suppress in

sensitive areas

Contain and suppress in

sensitive areas

Recommended

Control

-Fire

-Cultural

-Chemical

- Fire

-Cultural

-Chemical

- Fire

-Cultural

-Chemical

Spotted Knapweed (Centaurea maculosa)

Extent of Population Unknown 1.25 acres 1.25 acres

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

-Mechanical

-Chemical

-Mechanical

-Chemical

-Mechanical

-Chemical
124

Natural Zone Historic Zone Developed Zone

Sulfur cinquefoil (Potentilla recta)

Extent of Population 1.25 acres No known infestation No known infestation

Recommended Action Eradicate Eradicate Eradicate

Recommended

Control

- Mechanical

- Chemical

- Mechanical

- Chemical

- Mechanical

- Chemical

Timothy (Phleum pratense)

Extent of Population Unknown Unknown Unknown

Recommended Action Contain and suppress Contain Contain

Recommended

Control

-Fire -Fire -Fire

White sweetclover (Melilotus alba)

Extent of Population <20 acres <5 acres <5 acres

Recommended Action Contain and suppress Contain and suppress Contain and suppress

Recommended

Control

-Mechanical

-Fire (Propane flamer)

-Mechanical

-Fire (Propane flamer)

-Mechanical

-Fire (Propane flamer)

Yellow sweetclover (Melilotus officianalis)

Extent of Population <25 acres <5 acres <5 acres

Recommended Action Contain and suppress Contain and suppress Contain and suppress

Recommended

Control

-Mechanical

-Fire (Propane flamer)

-Mechanical

-Fire (Propane flamer)

-Mechanical

-Fire (Propane flamer)

Yellow toadflax (Linaria vulgaris)

Extent of Population <37 acres <12.5 acres <25 acres

Recommended Action Contain and then

eradicate

Contain and then

eradicate

Contain and then

eradicate

Recommended

Control

-Mechanical

-Chemical ~ 30 acres

-Biological

-Mechanical

-Chemical ~ 6 acres

-Mechanical

-Chemical ~ 6 acres
125

APPENDIX C Threshold level for 15 invasive exotic plants that

warrant chemical control

Species

Threshold Level for

Chemical Control

Acreage that

Exceeds the

Threshold

Amount of Herbicide

Required

Timetable for

Chemical

Control

Canada Thistle

(Limited control)

> 100 plants in any

one location where

control is warranted

such as 1⁄2 mile from

park boundary or in

other sensitive

locations.

~16 acres

with ~10

acres

identified

for control

Corn or Wheat

gluten – 15 gallons

Redeem – 25 Ozs. Or

2,4-D Amine – 6.25

gallons or

2,4-D LVE – 6.25

gallons or Transline

– 1.6 gallons

2 to 3 years

to treat all

locations

with

possible

follow-up

work

Cheatgrass

(Limited

control)

-Sugar applied at 160

grams per sq. meters

when < 100 square

meters

-Chemical when > 100

square meters or when

>10 square meters

when impacting a

revegetation site.

<1 acre Burnout – 2.5

gallons

Roundup – 14 to 70

ozs.

1 year

Common St.

Johnswort

> 100 plants at any

one location.

Eradicated

at the

present

time

0 0

Dalmatian

Toadflax

> 20 locations

(weed patches)

within the park, or

> 100 plants at any

one location.

3.5 acres Plateau + MSO – 40

ozs.

2 years to

treat all

locations

Diffuse

Knapweed

> 1000 plants in any

one location.

1.65 acre Transline – 10ozs. or

Tordon – 1 pint

1 year

Field

Bindweed

> 20 plants at any

one location

4.75 acres Paramount 1.78 lb.

or Rodeo 2 gallons

3 years to

treat all

locations

and

retreatment

if necessary

Houndstongue > 10 locations

(weed patches)

within the park, or

> 2,000 plants at

any one location.

2.5 acres Plateau + MSO – 40

ozs.

1 year

Leafy Spurge > 10 sq. ft. in any

one location

13.75 acres Plateau +MSO –

1.55 gallons.

3 years

Oxeye Daisy > 100 plants & > 2

locations

1 acre Escort – 2 0zs. 1 year

Orange

Hawkweed

> 100 plants in any

one location.

0.10 acre 2,4-D Amine – 0.5

pint

1 year
126

Species

Threshold Level for

Chemical Control

Acreage that

Exceeds the

Threshold

Amount of Herbicide

Required

Timetable for

Chemical

Control

Quack grass > 100 plants at any

one location

1 acre Roundup – 14 ozs. 1 year

Smooth brome

(Limited

Control)

>0.1 acre 5 acres

along Bear

Lake Road

Burnout – 2.5

gallons

Roundup – 1.1

gallons

1 year

Spotted

Knapweed

> 100 plants in any

one location.

0.80 acre Transline – 0.2 oz.

Or

Tordon – 0.2 oz. Or

2,4-D amine – 1 pint

1 year

Sulfur

Cinquefoil

> 10 locations

(weed patches)

within the park, or

> 100 plants at any

one location.

1 acre Tordon –0.5 pint or

Redeem – 2.4 ozs.

2 years

Yellow

toadflax

>1,000 plants at one

location or over

2,000 plants at more

than 10 locations

12.65 acres Telar – 34 ozs. 3 years to

treat all

locations

and

retreatment

if necessary
127

APPENDIX D Endangered, Threatened, and Rare Species of Rocky

Mountain National Park

Last Revised June 2003

Rocky Mountain National Park uses the following table to identify endangered, threatened and rare

species that must be protected if found within a proposed project site.

Agencies have a variety of ways of tracking and measuring the biological imperilment of species. The

U.S. Fish and Wildlife Service (USFWS) determines if a given specie needs protection under the

Endangered Species Act. There are four primary categories to federal listing that are applicable to Rocky

Mountain National Park:

Federal Status Codes

LE Federal Endangered – Listed as endangered by the U.S. Fish and Wildlife Service.

The specie is in danger of extinction throughout all or a significant portion of its range.

Endangered species have legal protection under federal law.

LT Federal Threatened – Listed as threatened by the U.S. Fish and Wildlife Service. The

specie is likely to become endangered within the foreseeable future. Threatened

species have legal protection under federal law.

C Federal Candidate – The U.S. Fish and Wildlife Service is considering federal listing.

PS:LT Partial Status – Infraspecific taxon or population is listed as Threatened in only a

portion of the species’ range

The Colorado Division of Wildlife also maintains a list of imperiled species for the state of Colorado.

There are three primary categories in the state listing:

State Status Codes

E State Endangered – Listed as endangered by the Colorado Division of Wildlife. Include

elements of native wildlife whose prospects for survival or recruitment within Colorado are in

jeopardy. State endangered species have legal protection under Colorado Revised Statues 33-2-

105 Article 2.

T State Threatened – Listed as threatened by the Colorado Division of Wildlife. Include

elements of native wildlife that are not in immediate jeopardy of extinction, but are vulnerable

due to small numbers, restricted throughout its range, or experiencing low recruitment or

survival. State threatened species have legal protection under Colorado Revised Statues 33-2-

105 Article 2.

SC State Special Concern – Listed as specie of special concern by the Colorado Division of

Wildlife.

The Colorado Natural Heritage Program (CNHP), based in Fort Collins manages a large database and

ranking system for Colorado species. The database can be accessed through the Internet at

www.cnhp.colostate.edu. The CNHP ranking system has two primary components – a ranking for the

global status of the specie (G), and a ranking for that part of the range found within the state (S).

Numeric extensions are added to these on a scale of 1 (critically imperiled) to 5 (demonstrably secure).

Natural Heritage ranks should not be interpreted as legal designations. Although most species protected

under state or federal endangered species laws are extremely rare, not all rare species receive legal

protection.

Global Rank Codes

G1 Critically imperiled globally because of extreme rarity (5 or fewer occurrences or very few

remaining individuals), or because of some factor of its biology making it especially vulnerable

to extinction.
128

G2 Globally imperiled because of rarity (6 to 20 occurrences), or because of other factors

demonstrably making it very vulnerable to extinction throughout its range.

G3 Globally vulnerable throughout its range or found locally in a restricted range (21 to 100

occurrences).

G4 Globally apparently secure, though it might be quite rare in parts of its range, especially at the

periphery (>100 occurrences).

G5 Globally demonstrably secure, although it may be rare in parts of its range, especially at the

periphery.

T# Rank applies to a subspecies or variety. These species are ranked on the same criteria as G1-

G5.

Q Taxonomic status is questionable.

? Indicates uncertainty about an assigned global rank.

State Rank Codes

S1 State critically imperiled; typically 5 or fewer occurrences, or because of some factor of its

biology making it especially vulnerable to extirpation from the state.

S2 State imperiled; typically 6 to 20 occurrences, or because of other factors demonstrably making

it very vulnerable to extirpation from the state.

S3 State vulnerable; typically 21 to 100 occurrences.

S4 State apparently secure; usually >100 occurrences.

S5 State demonstrably secure.

S#B Refers to the breeding season imperilment of species that are not permanent residents.

S#N Refers to the non-breeding season imperilment of species that are not permanent residents.

SX State extinct; unlikely to be rediscovered.

SR Recently reported in the state, but not confirmed.

? Indicates uncertainty about an assigned state rank.

The Rocky Mountain National Park list of Endangered, Threatened, and Rare Species does not include

State Ranks Codes S4 and S5 because these rankings indicate that the specie is secure throughout its

range. If a specie is listed as unconfirmed, it either means it occurred historically and is presently not

confirmed, or it is highly probable the specie occurs in the park, but is presently not confirmed.
129

Status CNHP Rank

Scientific Name Common Name

Time of

Occurrence Federal State Global State

Amphibians

Bufo boreas pop1 Boreal toad All year C E G4T1Q S1

Rana Pipiens

(unconfirmed)

Northern leopard

frog

All year SC G5 S3

Rana sylvatica Wood Frog All year G5 S3

Birds

Accipiter gentilis Northern goshawk All year G5 S3B

Aegolius funereus Boreal owl All year G5 S2

Amphispiza belli Sage sparrow Summer or

migrant

G5 S3B

Bucephala islandica Barrow’s

goldeneye

Winter or migrant SC G5 S2B

Buteo regalis Ferruginous hawk Migrant SC G4 S3B,

S4N

Catharus fuscescens Veery Summer or

migrant

G5 S1B

Catoptrophorus

semipalnatus

Willet Winter G5 S1B

Coccyzus americanus

occidentalis (unconfirmed)

Western Yellowbilled cuckooOnly two

recorded

occurrences,

1947& 1980

C SC G5T3 SR

Cypseloides niger Black swift Summer G4 S3B

Dendroica graciae Grace’s warbler Only one recorded

occurrence, 1990

G5 S3B

Dolichonyx oryzivorus Bobolink Summer or

migrant

G5 S3B

Egretta thula Snowy Egret Migrant or rare

summer

G5 S2B

Falco peregrinus anatum American

peregrine falcon

Summer or

migrant

SC G4T3 S2B

Glaucidium gnoma Northern pygmy

owl

All year G5 S3B

Grus canadensis tabida Greater sandhill

crane

Summer or

migrant

SC T4 S2B,

S4N

Haliaeetus leucocephalus Bald eagle All year LT T G4 S1B,

S3N

Leucosticte australis Brown-capped

rosy-finch

All year G4 S3B,

S4N

Loxia leucoptera White-winged

crossbill

All year, Irregular visitorG5 S1B

Numenius americanus Long-billed

curlew

Migrant SC G5 S2B

Pelecanus erythrorhynchos American white

pelican

Migrant SC G3 S1B

Plegadis chihi White-faced ibis Migrant G5 S2B

Seiurus aurocapillus Ovenbird Rare summer or

rare migrant

G5 S2B

Sterna forsteri Forster’s tern Migrant G5 S2B
130

Status CNHP Rank

Scientific Name Common Name

Time of

Occurrence Federal State Global State

Fish

Oncorhynchus clarki

pleuriticus

Colorado River

cutthroat

All year C SC T3 S3

Oncorhynchus clarki

stomias

Greenback

cutthroat

All year LT T T2T3 S2S3

Mammals

Canis lupis

(unconfirmed)

Gray wolf PS:LT G4 SX

Felis lynx canadensis

(unconfirmed)

Lynx All year PS:LT E G5 S1

Gulo gulo (unconfirmed) Wolverine All year E G4 S1

Plecotus townsendii

pallescens

Townsend’s bigeared batSummer.

Unconfirmed

winter.

G4T4 S2

Sorex hoyi montanus Pygmy shrew All year G5T2 T3 S2

Sorex nanus Dwarf shrew All year G4 S2

Ursus arctos

(unconfirmed)

Grizzly or Brown

bear

G4 SX

Invertebrates (Insects)

Colorado luski Lusk’s pinemoth Summer G4 S1?

Hyles galli Galium sphinx

moth

Summer G5 S3?

Paratrytone snowi Snow’s skipper Summer G5 S3

Pyrgus ruralis Two-banded

skipper

Summer (PS) G4 S3

Mollusk

Acroloxus coloradensis Rocky mountain

capshell

All year SC G1G2 S1

Plants

Aletes humilis

(unconfirmed)

Larimer aletes G2G3 S2S3

Alsinanthe stricta Rock sandwort G5 S1

Aquilegia saximontana Rocky mountain

columbine

G3 S3

Artemisia pattersonii Patterson's

wormwood

G3G4 S3

Asplenium septentrionale Grass-fern G4G5 S3S4

Botrychium echo Reflected

moonwort

G2 S2

Botrychium hesperium Western

moonwort

G3 S2

Botrychium lanceolatum

var lanceolatum

Lance-leaved

moonwort

G4T4 S3

Botrychium lunaria Moonwort G5 S3

Botrychium minganense Mingan

moonwort

G4 S1

Carex diandra Lesser panicled

sedge

G5 S1

Carex leptalea Bristle-stalk sedge G5 S1

Carex limosa Mud sedge G5 S2

Carex oreocharis A sedge G3 S1
131

Status CNHP Rank

Scientific Name Common Name

Time of

Occurrence Federal State Global State

Carex stenoptila River bank sedge G2 S2?

Chionophila jamesii Rocky mountain

snowlover

G4? S3S4

Cypripedium calceolus ssp.

Parviflorum

Yellow lady’s

slipper

G5 S2

Cyripedium fasciculatum Purple’s lady’sslipperG4 S3

Cystopteris montana Mountain bladder

fern

G5 S1

Draba crassa Thick-leaf

whitlow-grass

G3 S3

Draba fladnizensis Arctic Draba G4 S2S3

Draba grayana Gray’s peak

whitlow-grass

G2 S2

Draba porsildii Porsildraba G3G4 S1

Draba streptobrachia Colorado divide

whitlow-grass

G3 S3

Drymaria effusa var.

depressa

Spreading

drymaria

G4T4 S1SE?

Dryopteris expansa Spreading wood

fern

G5 S1

Erocallis triphylla Dwarf Spring

Beauty

G4? S2

Gastrolychnis kingii King’s campion G2G4Q S1

Gymnocarpium dryopteris Oak fern G5 S2S3

Hippochaete variegata Variegated

scouringrush

G5 S1

Isoetes setacea ssp.

Muricata

Spiny-spored

quillwort

G5?T5? S2

Juncus tweedyi Tweedy rush G3Q S1

Juncus vaseyi Vasey bulrush G5? S1

Lewisia rediviva Bitteroot G5 S2

Liatris ligulistylis Gay-feather G5? S1S2

Lilium philadelphicum Wood lily G5 S3S4

Listera borealis Northern

twayblade

G4 S2

Listera convallarioides Broad-Leaved

twayblade

G5 S2

Luzula subcapitata Colorado woodrushG3? S3?

Mimulus gemmiparus Weber monkey

flower

G2 S2

Nuttallia sinuata Wavy-leaf

stickleaf

G3 S2

Nuttallia speciosa Jeweled

blazingstar

G3? S3?

Papaver kluanense Alpine poppy G5T3 T4 S3S4

Parnassia kotzebuei Kotzebue grassof-parnassusG4 S2

Penstemon harbourii Harbour

beardtongue

G3 S3S4

Polypodium hesperium Western polypody G5 S1S2
132

Status CNHP Rank

Scientific Name Common Name

Time of

Occurrence Federal State Global State

Potentilla effusa Var.

rupincola

Rocky mountain

cinquefoil

G5?T2 S2

Pyrola picta (unconfirmed) Pictureleaf

wintergreen

G4G5 S3S4

Ranunculus gelidus ssp

grayi

Tundra buttercup G4G5 S2

Salix serissima Autumn willow G4 S1

Sisyrinchium pallidum Pale blue-eyed

grass

G2G3 S2

Telesonix jamesii James’ telesonix G2G3 S2?

Tonestus lyallii Lyall haplopappus G5 S1

Viola Selkirkii Selkirk violet G5? S1
133

APPENDIX E List of sources used by Rocky Mountain National

Park to identify endangered, threatened and rare species that must

be protected if found within the proposed project site.

Andrews, T. 1991. A Survey of Rocky Mountain National Park and Surrounding Areas of Arapaho and

Roosevelt National Forests for Wolverine and Lynx, Winter 1990-1991.

Armstrong, David M. 1987. Rocky Mountain Mammals. A Handbook of Mammals of Rocky Mountain

National Park and Vicinity.

Colorado Bird Observatory. 1997 Reference Guide to the Monitoring and Conservation Status of

Colorado’s Breeding Birds. Colorado Bird Observatory, Brighton, Co.

Colorado Division of Wildlife. 1998. Endangered, Threatened and Special Concern species.

Colorado Natural Heritage Program. 1997. Colorado’s Natural Heritage: Rare and Imperiled Animals,

Plants, and Natural Communities. Volume 3, No. 1. Colorado Natural Heritage Program, Fort Collins,

Colorado.

Denver Botanic Gardens. 1999. ROMO Working Herbarium. 1998 Herbarium Collection Summary.

Denver Botanic Gardens. 2000. ROMO Rare Plant Survey, Final Report 2000 Rare Plant List Occurrence

Records.

Reed, D.F., G. Byrne, J. Kindler. 1998. Snowshoe Hare Density/Distribution Estimates and Potential

Release Sites for Reintroducing Lynx in Colorado. Colorado Division of Wildlife Report.

Spackman, S., B. Jennings, J. Coles, C. Dawson, M. Minton, A. Kratz, and C. Spurrier. 1997. Colorado

Rare Plant Field Guide. Prepared for the Bureau of Land Management, the U.S. Forest Service and the

U.S. Fish and Wildlife Service by the Colorado Natural Heritage Program.

U.S. Bureau of Land Management. 1998. Bureau of Land Management Sensitive Species List for

Colorado.

U.S. National Forest Service. 1998. Rocky Mountain Region Sensitive Species List.

U.S. Fish and Wildlife Service. 1995. Migratory Nongame Birds of Management Concern in the United

States: The 1995 List.

U.S. Fish and Wildlife Service 1996. Candidates for Endangered Species Act Protection. 1996 Notice of

Review, Questions and Answers.

U.S. Fish and Wildlife Service. 1997. Endangered and threatened wildlife and plants; review of plant and

animal taxa that are candidates for listing as endangered or threatened species. 50 CFR 17.11 and 17.12.

52pp.

U.S. National Park Service. 1994. Memorandum of Understanding with the U.S. Fish and Wildlife

Service, Bureau of Land Management, and the National Marine Fisheries Service.

U.S. National Park Service. 1996. Automated National Catalog System (ANCS) for Rocky Mountain

National Park.

U.S. National Park Service. 1996. Memorandum on Interim Category 2 Candidate Species Guidance.
134

U.S. National Park Service. 1998. Checklist of Birds of Rocky Mountain National Park.

U.S. National Park Service. 1998. Wildlife Observation Database for Rocky Mountain National Park.

Rocky Mountain National Park.

Weber, W.A. 1976. Rocky Mountain Flora. Colorado Associated University Press, Boulder, Colorado.

Weber, W.A. 1988. Catalogue of the Vascular Plants of Rocky Mountain National Park. University of

Colorado Museum. Boulder, Co. 2nd Edition. 103 pp.

Yeatts, L. 1990. Botanical Survey of Rocky Mountain National Park. The Denver Botanic Gardens.

Denver, Co. 41pp.Yeatts, L. 1987. Survey of Special Interest Plants and General Flora, Rocky Mountain

National Park. The Denver Botanic Gardens, Denver, Colorado.
135

APPENDIX F Communications Plan for Herbicide Use within

RMNP

1. By April 30 of each year, park personnel will identify locations in the park where

herbicide application is warranted. Herbicide treatment will not be done outside of

the identified locations. RMNP will identify trail segments, trailheads, picnic areas,

parking lots and campsites that are located within or adjacent to the planned

treatment areas. RMNP will also identify all campgrounds in the park that will

remain chemical free for that year. This information will be made available to the

public via the RMNP website and other print media.

2. The following individuals and entities will be notified in writing of the proposed

herbicide application plan developed in #1:

a) All park inholders located within 1⁄4 mile of the proposed treatment sites.

b) All adjacent landowners located within 1⁄4 mile of the proposed treatment sites.

c) All individuals listed on the Colorado Registry of Pesticide Sensitive Persons.

RMNP will obtain a new registry each year from the Colorado Department of

Agriculture, Division of Plant Industry

d) The RMNP Information Office.

e) The RMNP Fee Collection Supervisor (entrance gate personnel).

f) RMNP District Law Enforcement Rangers

g) The RMNP Public Information Officer.

h) RMNP Dispatch Center

i) The information be included in the RMNP Morning Report, which is available

to all park employees with intranet access.

j) The information will be included on the RMNP web page, which is available to

the public.

3. The Information Office will keep a list of all hiking trail segments, trailheads,

parking lots, picnic areas, and campsites that are located within planned herbicide

treatment areas. The Information Office will also keep a list of all campgrounds in

the park that will remain chemical free for that year. These lists will be updated

annually.

4. All sites where herbicides are proposed to be applied will be posted with yellow

signs that contain the following information:

a) Treatment Date

b) Targeted invasive exotic plants

c) Name of the herbicide to be applied.

d) Restricted travel period.

e) Contact Name and Telephone Number.

Signs will be posted at access points (e.g. trailheads) two weeks before application.

Signs will remain in place for three months following application.
136

APPENDIX G Relative Aquifer Vulnerability Evaluation (RAVE)

As adapted from the Users Guide for the Vegetation Management Risk Assessment

Risk Assessment for Herbicide Use in Forest Service

Regions 1, 2, 3, 4, and 10 and on

Bonneville Power Administration Sites

December 1992

The USFS adapted their RAVE from the Montana Department of Agriculture,

Environmental Management Division.

Introduction

To help RMNP reduce the potential for contaminating groundwater with herbicides, an

aquifer vulnerability scoring system – Relative Aquifer Vulnerability Evaluation

(RAVE) – was adapted to the park. This numeric scoring system will help RMNP

evaluate herbicide selection for on-site groundwater contamination potential. RAVE is

designed only as a guidance system and does not replace the need for safe and judicious

herbicide application required in all situations.

Wetlands, rivers, streams and lakes, and areas of the park where groundwater is within

20 feet of the surface are particularly vulnerable to herbicide contamination and thus

require special consideration prior to making an application. The use of the score card

may indicate whether an alternative herbicide should be used within a given area, or if

the area is not suited to herbicide applications. If the area is not suitable for herbicide

use, other control methods should be used such as mechanical, cultural, biocontrol,

natural chemicals and/or the hot water low risk method hot water.

Several major factors in a particular area determine the relative vulnerability of

groundwater to herbicide contamination. Nine of these factors have been incorporated

into the RAVE score card and are defined below. A value for most of these factors can

be determined by a simple on-site inspection. Soil and water level information exists

for the park in areas where a herbicide might be used. Herbicide leaching potential is

based on the persistence and mobility of an herbicide in the soil. A list of leaching and

surface runoff potentials for herbicides planned for use in RMNP is given on the

attached table.

Factor Definitions

Depth to Groundwater: Distance in vertical feet below the soil surface to

the water table.

Soil Texture: Soils predominately gravelly, sandy, loamy, or

clayey.

Percent Organic Matter: The relative amount of decayed plant residue in

the soil may be estimated by soil color; darker soil

generally indicates higher organic matter (most of

the soil in the park is less than 3 percent).
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Topographic Position: Physical surroundings of the location where the

herbicide application is to be made.

• Flood Plain = within a river, stream or lake

valley such as Moraine Park, Hollowell Park,

Horseshoe Park, Kawuneeche Valley

(vegetation is composed of wetland species

such as sedges and willow.

• Alluvial Fan or Bench = lands immediately

above a river or lake valley but may still have

some riparian vegetation such as willow or

aspen (example would be the alluvial fan in

Endo Valley, or aspen in Upper Beaver

Meadows).

• Upland Habitat = uplands above a floodplain or

alluvial bench such as sagebrush, antelope

bitterbrush, aspen and ponderosa pine savanna.

• Transition zone = land not immediately

affected by open water (for example lodgepole

pine and spruce/fir near a wetland, stream or

river. Lodgepole and spruce/fir could be

adjacent to a stream, river, lake, floodplain.

Distance to Surface Water: Distance in feet from treatment boundary to the

nearest flowing or stationary surface water.

Annual Precipitation: • > 60” annual precipitation.

• 30-60” annual precipitation.

• < 30” annual precipitation on the treatment site.

Herbicide Application Frequency: Number of times the particular herbicide is

applied during one growing season.

Herbicide Application Method: Whether the herbicide is applied to the soil or to

the plant.

Herbicide Leachability: A relative ranking of the potential for a herbicide

to move downward in soil and ultimately

contaminate groundwater based upon the

persistence and mobility of the herbicide.
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Direction for Use of the RAVE Score Card

The RAVE score card can be completed in a matter of minutes. On a separate sheet of

paper write down the appropriate value for each of the nine factors listed on the score

card. Once all of the factors have been assigned a value, the values should be totaled.

Interpretation of RAVE Score

Higher numbers indicate high vulnerability of groundwater to contamination by the

herbicide used in the evaluation. RAVE scores greater than or equal to 65 indicate a

potential for groundwater contamination. RMNP will always be evaluating information

to determine herbicides that maybe appropriate. A RAVE score of 80 or greater

indicate that herbicide applications should not be made at this location with the

proposed product. Scores between 45 and 65 indicate a moderate to low potential for

groundwater contamination and scores less than 45 indicate a low potential for

groundwater contamination by the herbicide being evaluated. Even in such cases,

careful use of herbicides and adherence to label instructions is imperative to protect

groundwater.

Note: Some products such as Telar are used in very small quantities. In cases where

less than 1⁄2 pound AI per acre is applied, it would be reasonable to reduce the final

RAVE score by 2-5 points.
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THE RAVE SCORE CARD (circle one of each category)

Depth to Groundwater Annual Precipitation

* 2-10 ft. 20 >60” 5

10-25 ft. 12 30-60 “ 2

25-50 ft. 5 <30” 0

> 50 ft. 0

Soil Texture Herbicide Application Frequency

Gravelly 15 >1/yr 5

Sandy 15 1/yr 2

Loamy 10 <1/yr 1

Percent Soil Organic Mater Herbicide Application Method

0-1% 5 Applied to Soil 5

**1-3% 3 Applied to Foliage 2

>3% 2

Topographic Position ***Herbicide Leaching Potential

Flood Plain 15 Large 20

Alluvial Bench 10 Medium 10

Upland Habitat 5 Small 5

Transition Zone 2

Distance to Surface Water Total all Rankings

0-100 ft. 5 _______ = Rave Score

100-500 ft. 3

>500 ft. 2

* If water table is less than 2 feet deep applications should not be made or possibly

done with a wick or wand applicator, but only for a herbicide that can be used with that

method in wetland habitat.

** If unknown use this value

*** See attached Table (Herbicides and their Properties) for leaching potential for the

pesticide in question.
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Herbicides and their Properties

(for use with the Rave Scorecard)

Common

Name

Trade

Name

Solubility in

Water ppm

Soil Sorption

Index (Koc)

Half Life in

Soil (days)

Surface

Runoff

(Loss)

potential

Leaching

ChlorsulfuronTelar 300 (pH 5)

28,000 (pH7)

40 @ pH7

(avg.)

30 – acid

soil

30+ alkaline

Small Large

Clopyralid Transline 1,000 (acid)

300,000 (salt)

1.4 20 Small Large

2,4-D

Amine

890 20 10 Small Medium

2,4-D

Easter

900 100

(Estimated)

10 Medium Small

Glyphosate Roundup

& Rodeo

12,000 24,000 30 Large Small

Imazapic Plateau 2,200 10-26 31 - 410 Small Medium

Metsulfuron

methyl

Escort 548 @ pH5

2,790@ pH7

213,000@

pH9

35@ pH 7 120 Medium Large

Picloram Tordon 430 Avg. 16 90 Small Large

Triclopyr Redeem 430 780 46 Large Medium

Quinclorac Paramount 69 13 to 54 18-176 Variable Medium
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APPENDIX H Biological Control Insects

Leafy spurge - Aphtona lacertosa & Aphtona flava - 7,000 released in 2001 and 17,000

in 2002.

Canada thistle - Ceuforhynchus litura - possible release but further research is needed

to determine if the insects feed on native thistles.

Common St. Johnswort - Chysolina guadrigemina & Chysolina hyperici - currently we

do not have any St. Johnsonwort in the park. It was eradicated and the preferred

method of control is mechanical treatment if a new infestation is found. Biocontrol

would only be used if the infestation is beyond mechanical control.

Diffuse knapweed - Larinus minutus - this insect may pose a possible risk to native

plants closely related to knapweeds. Further research would be needed before any

release in the park. Currently, diffuse knapweed in the park is in small patches that are

below the threshold warranting biocontrol releases.

Spotted knapweed - Agapeta coegana & Sphenoptera jugoslavica - these insect may

pose a possible risk to native plants closely related to knapweeds. Further research

would be needed before any release in the park. Spotted knapweed in the park is also

currently below the threshold warranting a biocontrol release.

Musk thistle - The biocontrol insect Rhinocyllus conicus already exists in the park, but

was not released by the NPS. The insect moved into the park from releases outside the

park. It is presently having a negative impact on native thistles in the park.

Yellow toadflax – Calophasia lunula, Eteobalea intermediella & Mecinus janthinus -

These insects may pose a possible risk to native plants closely related to toadflax.

Further research funded by RMNP and the University of Colorado is scheduled to start

in 2003 with results submitted to RMNP in the spring of 2005.
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APPENDIX I Letter from Colorado Commissioner of Agriculture
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APPENDIX J Invasive Exotic Plants to Watch for in Colorado

Published in 1993 by:

Richard R. Old, Ph.D.

Post Office Box 272

Pullman, Washington 99163

• Abutilon theophrasti*

• Acroptilon repens

• Aegilops cylindrica*

• Alhagi pseudalhagi

• Anchusa arvensis

• Anchusa officinalis

• Anithrisus caucalis

• Anthrisus sylvestris

• Anthoxanthum odoratum

• Apera interupta

• Bryonia alba

• Carduus acanthoides*

• Carduus nutans*

• Carduus pycnocephalus

• Carthamus lanatus

• Centaurea calcitrapa

• Centaurea diffusa*

• Centaurea maculosa*

• Centaurea pratensis*

• Centaurea solstitialis*

• Chaenorrhinum minus

• Chondrilla juncea*

• Crupina vulgaris*

• Cynosurus echinatus

• Cytissus scoparius

• Echium vulgare

• Euphorbia cyparissias*

• Euphorbia esula*

• Euphorbia myrsinites*

• Galiopsis tetrahit

• Galium pedamontanum

• Glaucium corniculatum

• Hieracium auranticum*

• Hieracium pratense

• Hypochaeris radicata

• Iris pseudacorus

• Isatis tinctoria*

• Lepidium latifolium*

• Linaria dalmatica*

• Linaria vulgaris*

• Lysimachia vulgaris

• Lythrum salicaria*

• Nardus stricta

• Onopordum acanthium*

• Peganum harmala*

• Picris echoides

• Potentilla recta*

• Reseda lutea

• Salvia aethopsi*

• Senecio jacobaea*

• Silybum marianum

• Sisymbrium irio

• Sphaerophysa salsula*

• Taeniatherum caput-medusae*

• Tamarix ramosissima*

• Tanacetum vulgare

• Torilis arvensis

• Verbascum virgatum

• Ventenata dubia

• Zygophyllum fabago

* Since 1993 these species have been found in the state and are being controlled. They

are currently listed on the State of Colorado Noxious Weed List, or are proposed for

listing in an amendment to the 2001 state list and are listed in

Table 1 on page 3.
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APPENDIX K Reference Material for Behavior of Synthetic

Herbicides in the Environment

Two federal documents are relevant to RMNP’s Invasive Exotic Plant Management Plan. These

documents are: Final Environmental Impact Statement for Vegetation Treatment on BLM Lands in

Thirteen Western States dated May 1991 (BLM 1991 FEIS); and Risk Assessment for Herbicide

Use in Forest Service Regions 1, 2, 3, 4 and 10 and on Bonneville Power Administration Sites,

September 1992, USDA, Forest Service (FS 1992 Risk Assessment). The Final Environmental

Impact Statement for Vegetation Treatment on BLM Lands evaluates the effects of proposed

treatment methods on several resources including, but not limited to: vegetation, soils, aquatic

resources, fish and wildlife, cultural resources, recreation, and livestock. The U.S. Forest Service

Risk Assessment for Herbicide Use evaluates the effects of herbicides on natural systems and

human health and safety.

The human toxicity potential (HTP) is an indicator of the danger posed by a chemical’s release

to air or surface water. It was developed to compare emissions in life-cycle assessment and

public emissions inventories (Hertwich et al. 2001, 2000). HTP data are available on the

following web site: http://design.ntnu.no/ansatte/hertwich/HTP_ETC.html. Evaulations of

potential human health effects caused by heribicide exposure are generally based on results of

toxicity tests in laboratory animals. In summary, risk assessments conducted on the various

herbicides proposed for use in RMNP quantified general systemic and reproductive human

health risks for a given herbicide by dividing the dose found to produce no ill effects in

laboratory animals studies by the exposure a person might get from applying the herbicide or

from being near an application site. Members of the general public may be exposed to

herbicides via dermal, respiratory, and dietary routes (e.g. contact with vegetation at a recently

treated site, breathing herbicide vapors in or near recently treated areas, touching or eating

berries with residues). By implementing the mitigation measures in Chapter 7 (see page 104),

employee and park visitor exposure would be minimized.

It is unlikely that the general population would receive doses above “no observed effect” levels

for the synthetic herbicides and the amount proposed for use in RMNP. For further information

refer to the following web pages:

• USDA risk analyses for herbicides – http://www.fs.fed.us/foresthealth/pesticide/

• EPA assessing health risks for pesticides

http://www.epa.gov/pesticides/factsheets/alpha_fs.htm

• http://www.infoventures.com/e-hlth/

Other pertinent internet web pages related to invasive exotic plants and synthetic

herbicide information:

• Purdue University Agricultural Communication – http://www.agcom.purdue.edu/

• USDA Pesticide Fact Sheets – http://infoventures.com/e-hlth/pestcide/pest-fac.html

• Extension toxicology network – http://npic.orst.edu/

• Toxicological documention center – http://www.envtox.ucdavis.edu/

• Environmental Protection Agency pesticide web site –http://www.epa.gov/ecotox/

• Department of Defense pest web site – www.afpmb.org

• A Strategic Plan for Managing Invasive Nonnative Plants on National Park System

Lands – http://www1.nature.nps.gov/wv/strat_pl.htm
145

• Colorado Department of Agriculture Biological Pest Control –

http://www.ag.state.co.us/DPI/

• Human Toxicity Potential (HTP) data –

http://design.ntnu.no/ansatte/hertwich/HTP_ETC.html

• Journal of Pesticide Reform v. 108 –

http://www.mindfully.org/Pesticide/2003/pesticide2003.htm

• The following web site will link data together when doing a search –

www.dogpile.com
146

APPENDIX L U.S. Fish & Wildlife Service Correspondence
147
148