EXECUTIVE SUMMARY 

EXECUTIVE SUMMARY 

EXECUTIVE SUMMARY 

Proposed Action and Purpose 

and Need 

The Bureau of Land Management (BLM), an agency 

of the U.S. Department of the Interior (USDI), 

administers vegetation on nearly 261 million acres

(public lands) in 17 states in the western U.S., 

including Alaska. Management and control of

vegetation on public lands for resource and habitat

enhancement is an important function of this agency, 

including management to reduce the risk of wildfires

to people and their property. 

The BLM is proposing to treat vegetation on

approximately 932,000 acres annually in 17 western

states in the U.S., including Alaska, using 14

currently-approved and four new herbicide active

ingredients. At present, the BLM treats about 300,000

acres annually using 20 approved herbicides. The

proposed action would reduce the risk of catastrophic

wildfires by reducing hazardous fuels, restoring firedamaged lands, and improving ecosystem health by 1) 

controlling weeds and invasive species; and 2)

manipulating vegetation to benefit fish and wildlife 

habitat, improve riparian and wetlands areas, and

improve water quality in priority watersheds. 

In recent years, the severity and intensity of wildfires

in the West has increased dramatically from levels in

the 1970s and 1980s, to a million or more acres 

annually. Changes in the vegetation on public lands 

have resulted in increases in hazardous flammable 

fuels. 

Much of the increase in hazardous fuels can be

attributed to fire exclusion policies over the past 100 

years. Contributors to the change include intermittentand long-term drought over the past 40 years and an

increase in the spread of noxious weeds species and 

invasive vegetation.

Invasive vegetation and noxious weeds are the

dominant vegetation on an estimated 35 million acres 

of public lands. The estimated rate of weed spread on 

western public lands in 1996 was 2,300 acres per day.

Invasive vegetation and noxious weeds degrade or

reduce soil productivity, water quality and quantity,

native plant communities, wildlife habitat, wilderness

values, recreational opportunities, and livestock

forage, and are detrimental to the agriculture and 

commerce of the U.S. and to public health. Weed 

infestations can become permanent if left untreated. 

In response to the threats of wildfire and invasive

vegetation and noxious weeds, the President and 

Congress have directed the USDI and BLM, through

implementation of the National Fire Plan, and the

Healthy Forests Restoration Act of 2003, to take more

aggressive actions to reduce catastrophic wildfire risk

on public lands. The actions would be taken to protect

life and property, and to manage vegetation in a

manner that provides for long-term economic 

sustainability of local communities, improved habitat

and vegetation conditions for fish and wildlife, and 

other public land uses. 

The BLM last assessed its use of vegetation treatment 

methods during the late 1980s and early 1990s, by

preparing Environmental Impact Statements (EISs) 

and Record of Decisions (RODs) that covered 

vegetation treatment activities in 14 western states in 

the continental U.S. These EISs evaluated the

environmental impacts associated with vegetation 

control and modification from the use of herbicides, in

addition to other treatment methods—manual,

mechanical, and biological control methods, and use of

fire—on approximately 500,000 acres of public lands a 

year in the western U.S. The EISs also evaluated the

human health and non-target species risks of using 20 

herbicide active ingredients on these public lands. 

This Vegetation Treatments Using Herbicides on

Bureau of Land Management Lands in 17 Western

States Programmatic EIS (PEIS) has two primary 

objectives: 

• Determine which herbicide active ingredients 

are available for use on public lands in the 

western U.S., including Alaska, to improve the 

agency’s ability to control hazardous fuels and 

unwanted vegetation. In addition to the

herbicides currently approved for use, 

additional active ingredients are being 

considered for use by the BLM in order to

address emerging weed problems associated

with public lands, such as downy brome 

(cheatgrass) and invasive aquatic species. 

BLM Vegetation Treatments Using Herbicides ES-1 June 2007

Final Programmatic EIS
EXECUTIVE SUMMARY

• In consultation with the U.S. Environmental 

Protection Agency (USEPA), U.S. Fish and 

Wildlife Service, and National Oceanic and 

Atmospheric Administration National Marine 

Fisheries Service, develop a state-of-thescience human health and ecological risk

assessment (ERA) methodology. This 

methodology would serve as the initial 

standard for assessing human health and 

ecological risk for herbicides that may become

available for use in the future. 

The BLM has also prepared a Vegetation Treatments

on Bureau of Land Management Lands in 17 Western

States Programmatic Environmental Report (PER)

describing the environmental impacts of using nonherbicide vegetation treatment methods on public

lands. Limiting analysis in the PEIS to the use of

herbicides, while analyzing other treatment methods in

the PER, was done because the primary issue of 

controversy identified through scoping, and which

required National Environmental Policy Act (NEPA) 

review, was the BLM’s continuing and proposed

increase in the use of herbicides in vegetation

treatment programs needed to implement the National

Fire Plan and related initiatives. The use of herbicides

has been affirmed as a central issue for analysis in all

past EISs considered in this document. The use of the

other non-herbicide techniques in an integrated pest

management approach has also been affirmed in all

previous EIS Records of Decision, and the BLM is not

proposing to make any decisions relative to the use of

non-herbicide vegetation treatment methods. 

Alternative Proposals 

Five program alternatives were developed for and 

evaluated in this PEIS, including the Preferred 

Alternative and the No Action Alternative. Alternative 

actions were developed that 1) allow the BLM to

continue its current use of 20 active ingredients in 14

western states, as authorized by earlier EIS RODs; 2)

allow for the use of 14 active ingredients currently

used by the BLM and four new active ingredients; 3) 

prohibit the use of herbicides; 4) prohibit the aerial

application of herbicides; or 5) prohibit the use of

sulfonylurea and other acetolactate synthase-inhibiting

active ingredients. These program alternatives address

many of the concerns raised during scoping, in

particular the public’s desire to see alternatives that

place less emphasis on the use of herbicides, while still

meeting the program’s purpose and need. Alternatives 

were also developed to ensure that the BLM complied

with federal, tribal, state, and local regulations. 

Alternative A – Continue Present 

Herbicide Use (No Action Alternative) 

Under this alternative, the BLM would be able to

continue to use 20 active ingredients approved for use 

in 14 western states under the earlier EIS RODs for 

each state. The BLM would also continue activities

conducted under burned area emergency stabilization

and rehabilitation and hazardous fuel reduction that are

evaluated by NEPA compliance documents prepared

by local BLM field offices. Under this alternative, an

estimated 305,000 acres would be treated annually

using herbicides. 

Alternative B - Expand Herbicide Use 

and Allow for Use of New Herbicides 

in 17 Western States (Preferred 

Alternative) 

This alternative represents the treatment of vegetation

using herbicides in 17 western states, including

Alaska, Nebraska, and Texas, states that were not

included in the earlier EIS assessments. Under the

Preferred Alternative, approximately 932,000 acres

would be treated annually using herbicides, based on

the herbicide use projections developed by BLM field

offices. Based on these projections, the majority of

treatments would occur in Nevada, Idaho, Oregon, and 

Wyoming. 

Under the Preferred Alternative, the BLM would be

able to use, in the western U.S., including Alaska, 14 

active ingredients that were approved for use in the

earlier RODs and for which an analysis of risks to 

humans and non-target plants and animals was 

conducted for this PEIS or by the U.S. Department of

Agriculture Forest Service (Forest Service). These 

active ingredients are 2,4-D, bromacil, chlorsulfuron,

clopyralid, dicamba, diuron, glyphosate, hexazinone,

imazapyr, metsulfuron methyl, picloram, sulfometuron 

methyl, tebuthiuron, and triclopyr. The remaining six

active ingredients currently approved for use by the

BLM⎯2,4-DP, asulam, atrazine, fosamine,

mefluidide, and simazine⎯have not been used by the 

BLM for several years, or their use has been limited to 

a very small number of acres. Although the risks to

humans from the use of these chemicals are not

significant based on evaluations done for the earlier 

EISs and a review of the literature for this PEIS, the

BLM Vegetation Treatments Using Herbicides ES-2 June 2007

Final Programmatic EIS
EXECUTIVE SUMMARY 

risks to non-target plants and animals, especially

species of concern, have not been adequately 

evaluated. Under this alternative, their use would be

discontinued. Should these chemicals be needed by the

BLM in the future, the BLM would consult ERAs, if 

available, or conduct their own ERAs, to assess the

risks to non-target and sensitive species. This analysis

would be supported by the appropriate NEPA

documentation and interagency consultation before 

these chemicals would be approved for use or applied

on the ground.

The BLM would approve four additional active

ingredients for use in all 17 states included in this 

PEIS: imazapic, diquat, diflufenzopyr (in formulation 

with dicamba), and fluridone. In addition, the BLM

would approve diflufenzopyr for use in the future as a 

stand-alone active ingredient if it becomes registered

for herbicidal use. These active ingredients and 

formulations could only be applied for uses, and at

application rates, specified on the label directions. 

Under the Preferred Alternative, the BLM proposes to

use new active ingredients that are developed in the 

future if: 1) they are registered by the USEPA for use 

on one or more land types (e.g., rangeland, aquatic)

managed by the BLM; 2) the BLM determines that the

benefits of use on public lands outweigh the risks to

human health and the environment; and 3) they meet 

evaluation criteria to ensure that the decision to use the

active ingredient is supported by scientific evaluation

through human health and ecological risk assessments 

and NEPA documentation. 

Alternative C - No Use of Herbicides 

Under Alternative C, the BLM would not treat

vegetation using herbicides and would not use new

chemicals that are developed in the future. The BLM

would continue to treat vegetation using fire, and

mechanical, manual, and biological control methods.

A PER has been prepared that accompanies this PEIS 

and discusses these treatment methods, proposed 

treatment levels during the next 10 to 15 years, and

likely impacts to natural and social resources on public

lands from these treatment methods. 

Alternative D - No Aerial Applications 

This alternative is similar to the Preferred Alternative

in that it represents the treatment of vegetation using

herbicides in 17 western states, including Alaska, 

Nebraska, and Texas, and use of the same active

ingredients as allowed under the Preferred Alternative.

Under Alternative D, however, only ground-based 

techniques would be used to apply herbicides and no

aerial applications of herbicides would be allowed,

which would reduce the risk of spray drift impacting

non-target areas. Based on information obtained from

field offices, an estimated 55% of herbicide treatments 

would occur using ground-based methods during the

next 10 years. Thus, the BLM would treat 

approximately 530,000 acres annually using herbicides

under this alternative. In comparison, during 1997 to

2005, approximately 66% of herbicide treatments were 

conducted aerially and 34% using ground-based

methods. 

Similar to the Preferred Alternative, the BLM would

use new active ingredients developed in the future if 

they followed protocols for use of new active

ingredients identified under the Preferred Alternative. 

Alternative E - No Use of Acetolactate 

Synthase-inhibiting Herbicides 

This alternative was developed based on an alternative 

proposal for vegetation management on public lands

submitted by the American Lands Alliance, an alliance

of several environmental and conservation groups. 

Under Alternative E, the BLM would not use

sulfonylurea and other acetolactate synthase-inhibiting

active ingredients approved in the earlier RODs, which 

are chlorsulfuron, imazapyr, metsulfuron methyl, and 

sulfometuron methyl. During 1999 to 2000, these

active ingredients comprised approximately 28% of 

the active ingredients used by the BLM. Since 2001,

however, these active ingredients have comprised 

approximately 8% of the active ingredients used by the

BLM. The BLM would be able to use 10 active 

ingredients in the 17 western states that were approved

for use in the earlier RODs and for which an analysis 

of risks to humans and non-target plants and animals 

was conducted for this PEIS. These active ingredients

are: 2,4-D, bromacil, clopyralid, dicamba, diuron,

glyphosate, hexazinone, picloram, tebuthiuron, and

triclopyr. The six other active ingredients currently

approved for use by the BLM⎯2,4-DP, atrazine, 

asulam, fosamine, mefluidide, and simazine⎯would 

not be used unless guidelines given for the Preferred

Alternative were met. 

The BLM would be allowed to use three additional 

active ingredients in all 17 states: diquat, diflufenzopyr 

(if it becomes registered for herbicidal use), and 

BLM Vegetation Treatments Using Herbicides ES-3 June 2007

Final Programmatic EIS
EXECUTIVE SUMMARY

fluridone. In addition, the BLM would be able to use a

formulation of diflufenzopyr and dicamba. These

active ingredients and formulations could only be

applied for uses, and at application rates, specified on 

the label directions. Under Alternative E, the BLM

would use new active ingredients developed in the

future if they followed protocols for use of new active 

ingredients identified under the Preferred Alternative 

and did not contain sulfonylurea and imidazolinone 

chemistry and other acetolactate synthase-inhibiting 

compounds. 

Under this alternative, the BLM would treat 

approximately 466,000 acres annually using 

herbicides. Spot herbicide treatments would be favored

over broadcast treatments. Herbicides use would be

discouraged in areas populated by amphibians. To 

protect Native American and Alaska Native resources,

the BLM would establish herbicide-free zones around 

culturally significant plant and wildlife resources. This

alternative would place greater emphasis on passive

restoration than the other alternatives.

Summary of Impacts 

The direct and indirect effects of herbicide treatment

alternatives on natural and socioeconomic resources

are evaluated in this PEIS. The cumulative effects that

result from the incremental impact of treatment actions 

when added to the effects of other past, present, and

reasonably foreseeable future actions are also 

evaluated for herbicide and non-herbicide treatments. 

Standard operating procedures would be used to

reduce impacts, and mitigation measures have been

proposed to reduce significant adverse impacts to more 

reasonable levels. 

Direct and Indirect Impacts 

In general, potential direct and indirect adverse 

impacts and benefits would be greatest under the 

Preferred Alternative and least under Alternative C.

Fewer acres would be treated, or treatments would not 

be conducted aerially, under the other herbicide

treatment alternatives, so risks and benefits would be

intermediate between the Preferred Alternative and

Alternative C.

Impacts from herbicide treatments on local and 

regional air quality would be minor for all alternatives.

Pollutant emissions would be greater under Alternative

D than the Preferred Alternative, even though 40%

fewer acres would be treated under Alternative D,

because of the large number of acres treated using 

ground-based application methods under Alternative 

D. None of the treatments would result in emissions 

that exceed Prevention of Significant Deterioration 

thresholds or National Ambient Air Quality Standards. 

None of the herbicides commonly used by the BLM

appear to result in adverse impacts to soil. Treatments 

would benefit soil by restoring natural fire regimes and 

slowing the spread of weeds, which should reduce soil

erosion and improve soil productivity. New herbicides

proposed for use have little adverse impact on soil. 

Several herbicides used, or proposed for use by the

BLM, are known groundwater contaminants. Effects to

surface water would be minor, and herbicide

concentrations in surface water should not exceed safe 

levels for human health. Herbicide use would improve 

watershed function and water quality, since many 

treatments would be targeted at watersheds where

water quality does not meet state or tribal standards. 

Adverse and beneficial impacts of alternatives would 

primarily be related to number of acres treated. Water

quality would not be impacted by herbicides under

Alternative C, but land health would deteriorate more 

rapidly than under the other herbicide treatment

alternatives because herbicides could not be used to 

control weeds and other vegetation. 

Herbicides pose risks to terrestrial and aquatic 

vegetation. Most aquatic herbicides, and several 

terrestrial herbicides, are non-selective and could 

adversely impact non-target vegetation. Accidental

spills and herbicide drift from treatment areas could be

particularly damaging to non-target vegetation,

including croplands and other vegetation found on

privately-owned lands near treatment areas. Herbicides

would help to control aquatic vegetation that chokes

waterways and impacts wetland function and values. 

Upland and riparian area treatments could control

weeds and other vegetation to reduce soil erosion and

reduce the risk of catastrophic fire. Risks to upland, 

wetland, and riparian vegetation from proposed

herbicides would be similar to, or less than, risks from

currently-available herbicides. Adverse impacts from

herbicides to terrestrial and aquatic vegetation would 

be least under Alternative C, while benefits would be

greatest under the Preferred Alternative. Buffer zones 

would be used to reduce the risks to vegetation from

herbicide treatments under all alternatives proposing

herbicide use.

Many of the herbicides currently available for use by 

the BLM pose risks to fish and wildlife. Accidental

BLM Vegetation Treatments Using Herbicides ES-4 June 2007

Final Programmatic EIS
EXECUTIVE SUMMARY 

spills and direct spraying of aquatic organisms could

kill or harm animals, or affect the health and behavior

of animals. Fish and wildlife could also forage on

vegetation that has been treated, or prey on other 

animals that have been exposed to herbicides, and be

harmed. All of the herbicides pose some risk to nontarget terrestrial and aquatic vegetation, and damage to

these plants could adversely impact habitats used by

fish and wildlife. Acetolactate synthase-inhibiting

herbicides are highly potent and can damage plants at

low application rates, but do not appear to create

unnecessary risks to aquatic organisms or wildlife. Of

the new herbicides proposed for use, diquat poses a

low to high risk to aquatic organisms and wildlife,

depending on application rate and receptor scenario;

fluridone, imazapic, and Overdrive® (a formulation of 

dicamba and diflufenzopyr) pose little or no risk to

aquatic organisms and wildlife. The risk for adverse

health effects to individual organisms would typically

be greater for threatened, endangered, and other 

special status species than for secure species, 

depending on the herbicide and the exposure pathway.

Furthermore, the risk for associated population-and

species-level effects would be much greater for many 

TES species, given their low numbers and fragmented 

habitats. Buffers would be used between treatment 

areas and aquatic habitats to reduce risks to aquatic

organisms. Buffers would also be used between 

treatment areas and habitats of special status species.

Livestock and wild horses and burros could be 

impacted by herbicides from an accidental spill, direct

spray, herbicide drift, or by consuming herbicidetreated vegetation. Effects to animals could include

death, damage to vital organs, decrease in growth,

decrease in reproductive output and condition of

offspring, and increased susceptibility to predation.

However, most herbicides currently available for use

by the BLM pose little or no risk to these animals. Of 

the new herbicides proposed for use, only diquat is

fairly toxic to livestock and wild horses and burros.

However, it would be used by the BLM as an aquatic 

herbicide, and frequent exposure to these animals 

would be unlikely. Risks from exposure to herbicides

for livestock would be further reduced by restrictions 

placed on livestock use of treated areas as directed on 

herbicide labels. 

While herbicide treatments could affect cultural or 

paleontological resources near or on the surface, they 

would be more likely to affect traditional cultural

practices of gathering plants and the health of Native

peoples. Cultural and paleontological resources could

be impacted by equipment, and to a lesser extent, by 

the chemicals in herbicides. A risk assessment was 

conducted to assess the risks to Native peoples from 

harvesting plants that could be treated with herbicides,

or from direct exposure to herbicide spray. Native

peoples would face risks when picking berries in areas

treated with diquat. They could also face risks when 

consuming fish contaminated with 2,4-D, hexazinone,

or picloram. Native peoples would face risk from

diquat or fluridone if these chemicals were 

accidentally spilled or used at maximum application 

rates. 

Herbicide treatments could affect visual, wilderness,

and recreation resources. Treatments would remove 

and discolor vegetation, making it less visually

appealing. Over the long term, landscapes should be

more appealing as native vegetation was restored.

Treatments in wilderness and other special areas

would detract from the “naturalness” of the area.

Although use of mechanical equipment would be

strongly discouraged in these areas, its use would 

create noise and reduce the wilderness experience.

Recreationists could be exposed to herbicides,

experience less visually-appealing landscapes, or find

fish and game less plentiful as a result of treatments. In 

addition, recreational areas could be closed for short 

periods of time after application to ensure treatment 

success and protect the health of visitors. 

Social effects would be minor at the scale addressed in 

the PEIS. There would be benefits to communities that

supply workers, materials, or services in support of

treatment activities. Some businesses, such as

recreation-based businesses and ranching operations, 

could be adversely affected if treatments closed areas 

used for recreation or by domestic livestock. There are 

potential environmental justice concerns because a

large number of Native peoples and other minority

groups live in the West and work in industries (e.g.,

forest products, herbicide applicator) or conduct

activities (e.g., gathering of plants for traditional uses,

recreation) that could potentially expose these groups

to treated areas. 

A human health risk assessment was conducted to

assess risks to humans from the use of herbicides. At 

typical application rates, workers would not be at risk

from use of herbicides except when using diquat, 2,4-

D, 2,4-DP, atrazine, bromacil, diuron, fosamine, 

hexazinone, mefluidide, simazine, or tebuthiuron. At

maximum application rates, there are also risks

associated with the use of chlorsulfuron, fluridone, and 

triclopyr. Public receptors would be at less risk. The

BLM Vegetation Treatments Using Herbicides ES-5 June 2007

Final Programmatic EIS
EXECUTIVE SUMMARY

BLM would not use 2,4-DP, atrazine, fosamine, 

mefluidide, or simazine under the action alternatives. 

Except for diquat, new herbicides proposed for use

pose few or no risks to workers or the public. To

reduce risks from diquat, treatments would occur away 

from high residential and subsistence use areas. 

Cumulative Impacts 

Treatments would contribute only minor amounts of 

pollutants to the air. Fire use would increase 

particulate matter in the air, but the amount of 

pollutants generated by fire use, and their effects on

human health, should be less than those from wildfire,

resulting in fewer pollutants accumulating than would

occur without treatments. Treatments would lead to

cumulative loss of soil from removal of vegetation and

erosion, but improvement in vegetative quality should

slow soil loss on public lands. Erosion has led to poor

water quality on portions of public lands. Treatments 

that slow erosion would also benefit water quality and

slow the cumulative loss of water quality. Over half of 

the wetlands in the U.S. have been lost since 

settlement by Europeans. Treatments would improve

wetland and riparian area functions and values and

slow erosion, which contributes to wetland

degradation on public lands. With improvement in 

these areas, habitat for fish and other aquatic 

organisms would also improve. However, many 

anadromous fish spend part or most of their lives off of

public lands, and thus would potentially have to cope

with poorer quality habitat while off of public land.

Fire exclusion and the spread of weeds have degraded

vegetation function and quality on public land and 

have led to a cumulative loss of vegetative 

productivity. Treatments would restore ecosystem

processes and slow this loss. Improvement in

vegetation characteristics would benefit wildlife. Some

species that have adapted to degraded ecosystems 

could lose habitat as native vegetation was restored, 

but most species would benefit. Factors that have led

to the loss of native vegetation and ecosystem health

have adversely impacted rangelands used by domestic 

livestock and wild horses and burros. Treatments 

should improve rangelands for these animals, and 

ensure that public lands can support viable populations

of wild horses and burros and a healthy ranching

industry. 

Treatments could add to the cumulative loss of

paleontological and cultural resources, but risks would 

be low. Treatments could impact plants used by Native 

peoples for traditional lifeway uses, and the health of 

Native peoples. However, the BLM would use

herbicides that are generally safe for use around 

people, and would conduct pre-treatment surveys to

identify areas of cultural concern before conducting

treatments to reduce the cumulative loss of these

values. 

Treatments would result in some short-term and

temporary loss of visual, recreational, and wilderness 

and other special area values due to vegetation being

killed or discolored. In some cases, areas might be 

closed to visitors during and after treatments; however, 

these impacts would be short-term and any values 

affected would be restored within two growing seasons

in most cases.

Treatments would benefit local communities by

providing jobs and income, and by reducing the risk of 

catastrophic wildfire that could harm people and

destroy property. These gains would be minor in the

context of the western economy, but would still be a

cumulative benefit for many rural communities. 

Treatments could harm the health of workers and the

public. Most herbicides, however, would pose few

risks to workers, and even fewer risks to the public, 

when applied at the typical application rate. New

herbicides proposed for use pose few or no risks,

except for diquat. If treatments restored natural fire 

regimes, reduced the risk of catastrophic fire, and 

slowed the spread of weeds, human health would 

benefit. 

Treatments could result in short-term loss of some

resources, including soil, vegetation, wildlife, and

livestock forage opportunities. Over the long term, loss 

of resource values would be slowed, and in some

cases, would be reversed. Short-term losses in resource

functions would be compensated for by long-term

gains in ecosystem health. 

BLM Vegetation Treatments Using Herbicides ES-6 June 2007

Final Programmatic EIS