The Wilderness Threats

Matrix: A Framework

for Assessing Impacts

David N. Cole

United States

Department

of Agriculture

Forest Service

Intermountain

Research Station

Research Paper

INT-475

April 1994
Intermountain Research Station

324 25th Street

Ogden, UT 84401

THE AUTHOR

DAVID N. COLE is Research Biologist for the Aldo

Leopold Wilderness Research Institute, P.O. Box 8089,

Missoula, MT 59807. Dr. Cole received his A.B. degree

in geography from the University of California, Berkeley,

in 1972. He received his Ph.D. degree, also in geography, from the University of Oregon in 1977. He has written many papers on wilderness management, particularly on the impacts of recreational use.

RESEARCH SUMMARY

This report proposes a comprehensive framework for

assessing threats to wilderness. The framework can be

depicted as a matrix with potential threats to wilderness

as columns and wilderness attributes intended for preservation as rows. Cells in the matrix represent the impacts

of each threat on each attribute.

The most generally significant threats to wilderness are

recreational use and its management, livestock grazing

and its management, mining, fire and its management,

exotic species introductions and invasions, water projects, atmospheric pollutants, and practices on adjacent

land. The primary wilderness attributes of concern are

air, aquatic systems, rocks and landforms, soils, vegetation, animals, ecosystems and landscapes, cultural resources, and opportunities for wilderness experiences.

The threats matrix will help wilderness planners, managers, and researchers. It can be used by planners

during the scoping process, in describing the current

management situation, in developing assumptions about

the future, and in assessing the impacts of alternative

management actions. It provides a comprehensive overview of monitoring needs. It can be used to assess

research and management priorities for individual wildernesses, regions, and the National Wilderness Preservation System.

The matrix was used to assess threats to wildernesses

in the Forest Service’s Northern Region (northern Idaho

and Montana). The significance of and knowledge about

threats were assessed by a team of wilderness experts.

The most significant perceived threat was fire and its

management; aquatic systems were the wilderness attribute considered to be most threatened. The difference between significance and knowledge was greatest

for fire and its management, suggesting that this is the

threat most in need of further research. Ecosystems,

landscapes, and aquatic systems are the wilderness

attributes most in need of further research.

ACKNOWLEDGMENTS

This report profited greatly from the assistance of the

Northern Region’s Wilderness Interdisciplinary Team,

particularly their assessment of the significance of and

knowledge about threats to wilderness.
CONTENTS

Page

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

Conceptual Framework ..............................................1

Threats ....................................................................2

Attributes of Wilderness Character .........................3

Potential Applications .................................................3

Planning and Monitoring Applications .....................3

Research Program Applications .............................4

Individual Wilderness Applications .........................5

Application to Northern Region Wilderness ...............5

Evaluation ...............................................................5

Impacts of Recreation and Its Management ...........6

Impacts of Livestock Grazing and

Its Management ...................................................6

Page

Impacts of Mining ....................................................7

Impacts of Fire and Its Management ......................7

Impacts of Exotic Species Introductions

and Invasions ......................................................8

Impacts of Water Projects .......................................9

Impacts of Atmospheric Pollutants .........................9

Impacts of Practices on Adjacent Lands ...............10

Significance of Threats to Northern Region

Wilderness .........................................................11

Research Gaps Concerning Threats to

Northern Region Wilderness .............................12

Conclusions..............................................................13

References ...............................................................14

1

INTRODUCTION

The 1964 Wilderness Act establishes stringent goals

for management of wilderness: preservation of natural

conditions and wilderness character, and provision of

outstanding opportunities for solitude or a primitive

and unconfined type of recreation. In addition, the Act

permits a number of specific uses in wilderness that

potentially threaten these goals: “Wilderness areas

shall be devoted to the public purposes of recreational,

scenic, scientific, educational, conservation, and historical use.” These uses of wilderness are often referred

to as conforming uses. The Act also allows for the continuance of certain “nonconforming” uses—mining on

valid claims that existed before 1984, livestock grazing, the establishment and maintenance of reservoirs,

administrative facilities, and the control of fire, insects,

and diseases. The Act does not specify how to resolve

potential conflicts between conforming, nonconforming or administrative uses of wilderness and the preservation of wilderness character. One of the primary

responsibilities of wilderness managers is to protect

wilderness character from the potential threats these

internal uses pose.

Managers’ responsibilities become even more daunting in light of the external threats to wilderness. Wildernesses do not exist in a vacuum; they are part of

larger landscapes and regions. Wilderness boundaries

may be relatively impermeable to chainsaws and mountain bikes, but they are highly permeable to pollutants,

migrating animals, exotic species, noise and light, wildfires, insects, and diseases.

Protecting wilderness from these potential threats

would be challenging even if managers had a substantial body of scientific knowledge to draw from. Unfortunately, little is known about the impacts of most of

these threats. Wilderness research and management

have traditionally been focused on problems associated

with recreational use. Other potential threats have

been largely ignored. Reaching the goal of effective

wilderness protection will require knowledge about the

entire spectrum of threats to wilderness, including effective ways to monitor these threats and mitigate their

impacts. An important step toward this goal is the

development of a comprehensive framework of threats

to wilderness and their impacts.

This report proposes such a framework—the wilderness threats matrix. This matrix will be a useful tool

to wilderness planners, managers, and researchers.

It can be used by planners during the scoping process,

in describing the current management situation, in

developing assumptions about the future, and in assessing the impacts of alternative management actions.

It provides a comprehensive overview of monitoring

needs. It can be used to assess research priorities, as

well as management priorities for individual wildernesses, regions, and the National Wilderness Preservation System. The report includes an example of one

of these applications, an assessment of the perceived

significance of threats to wilderness in the Forest Service’s Northern Region (northern Idaho and Montana).

CONCEPTUAL FRAMEWORK

Managers must be concerned about the impacts

that potential threats have on attributes of wilderness

character. These three terms are the basis of a conceptual model that can be applied in wilderness. I

define threats as human activities or the consequences

of human activities that have the potential to change

wilderness conditions. These threats can cause impacts to wilderness attributes. Using this terminology,

threats are the agents of change, while changes in

wilderness conditions are impacts to attributes. This

differs from the terminology of Machlis and Tichnell

(1985), who apply the term “threat” to both the agent

of change and the change itself.

The impacts caused by any single threat will differ

depending on the attributes the threat impacts. For

example, grazing’s impacts on vegetation differ from

grazing’s impacts on native animals. The impacts of

different threats on a single attribute will also differ.

For example, the effects of air pollution on vegetation

differ from the effects of fire suppression on vegetation. Consequently, managers need to understand

the linkages between each significant potential threat

and each individual wilderness attribute. Figure 1 displays linkages for eight potentially significant threats

to wilderness. Other threats are represented as well.

Finally, these potential threats will interact, causing

cumulative impacts; the figure recognizes these

interactions.

Separating the individual attributes of wilderness

character is even more artificial than separating

threats, because impacts occur at all spatial and

temporal scales, and some of the most significant

The Wilderness Threats Matrix: A

Framework for Assessing Impacts

David N. Cole
2

impacts affect interactions between attributes (such

as plant-soil interactions). I have identified nine individual attributes, along with an interaction box.

The framework for organizing information is most

conveniently displayed as a matrix (fig. 2), with the

threats forming columns and the attributes forming

rows. Each cell consists of the various impacts that

each threat causes to each attribute. For simplicity,

the interactions among threats are not included in

the matrix. Interactions among wilderness attributes

are an integral part of the ecosystems/landscapes attribute. In the future, highly significant cumulative

threats (such as the combination of fire suppression

and grazing) or interactions between attributes (such

as those that take place during nutrient cycling) could

be included in the matrix.

Threats

The following eight threats are considered the most

significant threats to wilderness character. They are

arranged from those that are primarily internal to

those that are primarily external. These definitions

were developed for Northern Region wildernesses

but could be modified for wildernesses elsewhere.

Recreation—The threat comes from onsite recreational users, as well as actions taken to manage that

use (such as trail construction). Figure 1—Linkages between potential threats

and the wilderness attributes they impact.

Figure 2—The threats matrix in which each cell represents the impacts that each

potential threat has on each wilderness attribute.

Recreation

Exotic

species

Water

projects

Atmospheric

pollutants

Potential

threats

Wilderness

attributes

Interactions

Rock/

landforms

Wilderness

experiences

Vegetation

Animals

Potential Threats

Recreation

Adjacent

Other

lands

Atmospheric

pollutants

Water

projects

Exotic

species

Mining

Fire

Livestock

Air

Aquatic

systems

Rock/

landforms

Soils

Vegetation

Animals

Ecosystems/

landscapes

Cultural

resources

Wilderness

Attributes of Wilderness Character

experiences

Interactions

Aquatic

systems

Soils

Ecosystems/

landscapes

Cultural

resources

Other

Adjacent

lands

Fire

Mining

Domestic

livestock

Air
3

Livestock—The threat is the grazing of livestock

(primarily cattle and sheep) and their management

(fencing, water supplies, and so on).

Mining—Both active and abandoned mines are

potential threats.

Fire—In most wildernesses the suppression of natural fires is a primary threat. However, other threats

related to fire include human-caused fires in the wilderness, suppression of fires that would otherwise have

burned into the wilderness, and impacts caused by fire

suppression activities.

Exotic Species—Exotic species have been intentionally and unintentionally introduced into wildernesses. Introduced plants, animals, and diseases are

all concerns, as are actions taken to manage them,

such as pesticide applications or biological control.

Water Projects—Dams and reservoirs occur in

some wildernesses; their existence, operation, and

maintenance can cause impacts. Other wildernesses

are impacted by water impoundments and diversions

upstream from the wilderness.

Atmospheric Pollutants—This threat is from

airborne pollutants, usually generated outside the

wilderness.

Adjacent Lands—Wilderness is threatened by a

wide variety of activities that occur on lands adjacent

to (and even some distance from) wilderness. Such

activities include resource extraction, water pollution,

habitat fragmentation, road development, and urban

development.

Other—A long list of other threats could be compiled, including global climate change, scientific use

of wilderness, aerial overflights, subsistence use of

wilderness, and even other laws and mandates, such

as the Clean Air Act, the Endangered Species Act, and

the National Historic Preservation Act.

Not all of these will be significant threats to every

wilderness. Some of these threats may not apply to

certain wildernesses; some threats that haven’t been

included may apply to other wildernesses.

Attributes of Wilderness Character

Nine important attributes of wilderness character

can be differentiated. These should apply to all wildernesses; important interactions also may need to

be specified.

Air—This refers to the physical and chemical characteristics of the lower atmosphere, including visibility.

Aquatic Systems—This refers to the physical, chemical, and biological components of aquatic systems.

Rocks/Landforms—This includes mineral, rock,

and landform features.

Soils—This refers to the physical, chemical, and

biological components of soil systems.

Vegetation—This refers to the composition, structure, and function of terrestrial plants and plant communities, including processes such as succession.

Animals—This refers to the composition, structure,

and function of terrestrial animals and animal communities, including processes such as migration.

Ecosystems/Landscapes—This refers to the composition, structure, and function of ecosystems, the

interaction between individual attributes. It also refers

to characteristics of systems at larger spatial scales,

such as landscapes. This complex of attributes might

be subdivided for certain purposes.

Cultural Resources—This includes the evidence

of previous occupation and use by prehistoric and historic peoples, as well as the current values of indigenous peoples.

Wilderness Experiences—This refers to the opportunities that visitors have to experience solitude, to

enjoy a primitive and unconfined type of recreation,

and to realize spiritual and educational values. Managers are not responsible for providing these values; they

are merely responsible for providing the opportunity.

POTENTIAL APPLICATIONS

The threats matrix has many potential applications

to wilderness management. It can be used as a planning tool or to provide the framework for a comprehensive monitoring program. It can be used to assess

research priorities or to develop a research program.

It can also be used to establish management priorities,

both for individual wildernesses and for larger aggregations of wilderness, such as those on a National

Forest or in a Forest Service Region.

Planning and Monitoring Applications

An increasing number of wilderness management

plans are based on the concept of Limits of Acceptable

Change (Stankey and others 1985); these plans devote

considerable attention to indicators. Indicators are

specific parameters that can be monitored to evaluate

the success of management programs. Successful wilderness management primarily entails protecting wilderness conditions (both biophysical and experiential)

from threats (human activities). Consequently, indicators need to be developed for the full range of significant threats and potential impacts to wilderness.

Most of the indicators developed to date relate only

to the threat posed by recreational use; other important

threats are largely neglected. For example, the Bob

Marshall Wilderness Limits of Acceptable Change Plan

only contains indicators for the effects of recreation
4

on soils, vegetation, and wilderness experiences. There

are no indicators of the impacts of recreation on the six

other attributes, or of the impacts of all other threats.

Of the 72 cells in the threats matrix, indicators were

developed for just three. Until effective indicators are

developed for a wider range of potential impacts, Limits of Acceptable Change planning will be severely

limited in scope. In future efforts, planners should

use the threats matrix as a comprehensive overview

of the range of potential wilderness concerns. Then,

they should try to develop indicators that reflect the

range of significant threats to the specific wilderness.

The threats matrix also may help managers think

more comprehensively about monitoring in wilderness.

In fact, the matrix has been adopted as part of a conceptual model of wilderness monitoring needs to be

used by the four Federal agencies that manage the

National Wilderness Preservation System (Cole and

others 1993). To protect wilderness, a wide variety of

potentially significant impacts need to be monitored.

So far, research on wilderness monitoring techniques

has been confined primarily to measuring recreation

use and its effects on soils, vegetation, and wilderness

experiences. Consequently, most wilderness monitoring

is confined to these three types of impact—representing

less than 5 percent of the full range of potential concerns (3 of the 72 cells). Monitoring techniques for

some of the other impacts included in the threats matrix have been developed for lands outside of wilderness, but these techniques need to be modified before

they can be readily used by wilderness managers.

Entirely new monitoring protocols need to be developed for other types of impacts.

Research Program Applications

The threats matrix also provides an overview of wilderness concerns that can help establish an agenda for

wilderness management research. For years, the only

federally funded research group devoted solely to wilderness management research has been the Forest Service’s

Wilderness Management Research unit, U.S. Department of Agriculture. Formerly part of the Intermountain Research Station, this group is now part of the Aldo

Leopold Wilderness Research Institute in Missoula,

MT. To date, this group has worked primarily on one

cell of the matrix, the effects of recreation on wilderness experiences. The group has conducted substantial research on two other cells, recreational impacts

on vegetation and soils. The other 95 percent of the

threats matrix has been virtually unexamined. Other

research groups have developed knowledge about other

threats to wilderness (such as fire suppression and air

pollution), while conducting research that was not devoted exclusively to wilderness. However, most of the

threats and impacts represented by the threats matrix

have received no more than minimal research attention.

Research programs need to provide managers with

five types of information about each cell in the threats

matrix.

Nature of Impacts—What are the impacts of the

threat on the attribute? For example, previous research has illustrated that fire suppression can alter

vegetation structure (Kilgore and Heinselman 1990)

and that recreational use can cause vegetation loss

and soil compaction (Cole 1987). Most threats will

have many different types of impact on each attribute.

Severity of Impacts and Factors that Influence

Severity—Once we understand the types of impact

that occur, we need to understand the magnitude of

impact and how certain factors cause magnitude to

vary. For example, research suggests that vegetation

loss caused by recreation can range from no perceptible

loss to complete denudation. Soil compaction caused

by recreation ranges from no perceptible compaction

to a severalfold increase. The amount of vegetation

loss and soil compaction is a function of factors such

as the amount of use, type of use, season of use, soil

moisture, and the durability of the vegetation. Much

has been learned about the influence of these factors

(Cole 1987; Kuss and others 1990). This knowledge

is important to managers because they can control the

severity of impacts by manipulating these factors.

Significance of Impacts—Knowledge about the

nature and severity of impacts can help managers

understand the significance of these impacts. Some

impacts—such as the effect of exotic species on air

quality—are likely to be insignificant. Others—such

as the effects of fire suppression on vegetation—are

highly significant because they influence the composition, structure, and function of ecosystems for long

periods over vast tracts of land. Specific criteria for

judging significance are not well defined; they require

integrating ecological concerns with human values.

However, judgments about significance are critical

to setting priorities related to threats and impacts.

Effectiveness of Management Strategies—

Numerous alternative strategies have been implemented in attempts to control the impacts of different

threats. Understanding the factors that influence the

severity of impacts can help identify strategies that

are likely to be effective. Once these strategies have

been implemented, research should attempt to evaluate their success.

Indicators and Monitoring Techniques—As

discussed previously, indicators need to be developed

for threats that are likely to have significant impacts

on wilderness. Information about the nature of impacts, along with an assessment of their significance,

can help identify important indicators. In addition,

researchers need to develop monitoring protocols for

likely indicators and test these protocols in the field.
5

This should allow managers to monitor the most significant threats to wilderness conditions cost effectively.

Individual Wilderness Applications

The threats matrix should also be used to establish

management priorities for individual wildernesses.

Wilderness managers need to gather information

about the extent and severity of threats to their wilderness and the impacts of these threats. This information can be used, along with research information

about the nature of impacts and public concern, to assess the relative significance of threats and impacts.

The application to Northern Region wilderness that

follows illustrates how this can be done based on group

judgment.

Highly significant threats and impacts should be high

priorities for management. These priority items should

be among the issues and concerns that drive management plans. They should be the focus of monitoring

efforts and other wilderness management programs.

There may be very little information about threats or

impacts that are thought to be highly significant. A

critical need exists to gather information about the

extent and severity of these impacts.

The cells in the threats matrix can also be used as

categories for compiling and accessing information

about impacts to wilderness. Separate files—either

electronic or paper—can be kept for each combination

of threat and attribute. Literature about these impacts,

monitoring data, and experience with mitigation can

be stored in these files.

APPLICATION TO NORTHERN

REGION WILDERNESS

To illustrate one application of the threats matrix,

I conducted an assessment of threats to and impacts

on the 15 wildernesses in the Forest Service’s Northern Region. These wildernesses encompass more than

5 million acres (fig. 3). Each threat is briefly described,

its most obvious impacts are mentioned, and a few basic references are provided. Finally, the significance of

and current knowledge about the threats are evaluated.

Evaluation

Members of the Northern Region’s Wilderness Interdisciplinary Team were given the threats matrix (fig. 2)

and asked to evaluate the significance of and knowledge about the actual or foreseeable impacts each potential threat has had on each wilderness attribute.

The criteria used to derive significance ratings were

(1) extent and (2) importance. Extent refers to how

many wildernesses experience the impact and the proportion of the wilderness that is impacted. This part

of the rating is relatively objective.

Importance is more subjective and was based on

an assessment of the likely longevity of the impact, the

rarity of the attributes being impacted, and the extent

Figure 3—Wildernesses in the Forest Service’s Northern Region.

Great Bear

Bob Marshall

Scapegoat

Gates of the Mountains 0 100

miles

Absaroka-Beartooth

 Lee

Metcalf

Frank Church-River

of No Return

Gospel

 Hump

 Hells

Canyon

Mission

Mountains

Cabinet

Mountains

Anaconda-Pintlar

IDAHO

MONTANA

Welcome Creek

Selway-Bitterroot •Missoula

•Moscow

Rattlesnake
6

to which ecosystem function is altered. Ratings were

on a scale from 1 (low significance) to 5 (high significance). Highly important but localized impacts and

very extensive but relatively unimportant impacts

would be rated 3. An impact that is both moderately

widespread and moderately important would also be

rated 3. An impact that is unimportant would be

rated 1 regardless of its extent.

Knowledge was also rated on a scale from 1 (little

knowledge) to 5 (much knowledge). The types of knowledge under consideration were the nature, significance,

extent, and severity of impacts. Knowledge about appropriate management or monitoring of these impacts

was not considered. This is an important distinction

because some impacts are quite well understood, although there is no cost-effective way to monitor them.

The criteria used to derive knowledge ratings were

knowledge of cause-and-effect relationships and empirical data about the extent and severity of impacts.

For example, if cause-and-effect relationships are obvious from common sense, but there is little data on

extent or severity, the rating would be 3. Ratings are

relative to each other and assess how much is known—

not how much more needs to be learned. Ratings of

5 mean that cause-and-effect relationships are well

understood with substantial empirical data on the impacts. A rating of 5 does not mean that much more

could not be learned. Knowledge ratings were not

assessed for impacts considered insignificant (those

cells given a significance rating of 1).

Impacts of Recreation and Its

Management

Recreational use of wilderness affects physical and

biological resources (Hammitt and Cole 1987; Kuss

and others 1990). Aquatic systems are affected when

trails and other denuded areas erode, increasing sediment loads and turbidity, when waters are polluted by

wastes from humans or livestock, and when fish are

planted in fishless lakes. Soil and vegetation are severely affected along trails, in campsites, grazed meadows, and other areas where use is concentrated. Soils

are physically, biologically, and chemically altered and,

in some cases, eroded away because of impacts associated with recreation. Plants are injured and killed,

reducing vegetation abundance and changing the community’s composition. Animals are affected when recreationists disturb their habitat, approach them too

closely, or kill them.

Recreational use can also result in conflict between

wilderness visitors and diminish perceptions of solitude

(Manning 1985). These impacts reduce opportunities

for high quality wilderness experiences. Attempts

to manage recreational use also cause impacts. Use

restrictions can reduce access to the wilderness and

diminish the “unconfined” nature of the recreational

experience. Development of facilities to reduce resource damage can diminish the “primitive” nature

of the experience. Facility construction, particularly

trail construction, can also impact physical and biological resources.

These impacts occur throughout Northern Region

wildernesses, although they are most severe in the

more heavily used portions of the most popular wildernesses (such as lake basins in the Absaroka-Beartooth

or the Cabinet Mountains and river corridors in Hells

Canyon or in the Frank Church-River of No Return

Wilderness). The most significant perceived impacts

of recreation use in Northern Region wilderness are

to aquatic systems, animals, and wilderness experience

opportunities (fig. 4). Impacts on vegetation, soils, and

cultural resources can be locally severe, but are of limited significance at the landscape scale. Our knowledge

is greatest about impacts to vegetation, soils, and wilderness experiences. The greatest discrepancy between significance and knowledge is for impacts to

aquatic systems and animals. Additional knowledge

is needed for all types of recreational impact, but these

two topics are particularly critical research needs.

Impacts of Livestock Grazing and Its

Management

Livestock grazing is allowed in wilderness if it was

an established use before designation. Moreover,

guidelines contained in the Colorado Wilderness Act

(P.L. 96-560) make it clear that Congress considers

Figure 4—The significance of recreational

impacts on each wilderness attribute and

knowledge about the impacts. Attributes

below the diagonal line of equal significance and knowledge ratings are the

ones most in need of further research.

Vegetation

Soils

Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

•

•

Cultural resources

Experiences

Air

Rock/landforms

Ecosystems/landscapes

•

•

•

•
7

grazing in wilderness to be appropriate and intends

that it be maintained. However, the trampling and

grazing of sheep and cattle do cause impacts on physical and biological conditions in wilderness (Vallentine

1990). The physical, biological, and chemical characteristics of soils can be altered by grazing, as can the

abundance and composition of vegetation. Aquatic

systems and channel morphology can also be changed

(Platts 1981). Visitors can be displeased when they

encounter livestock or the evidence of livestock grazing. Fences, line cabins, water wells, stock tanks, and

similar facilities also impact physical resources, wilderness, and experiences, as does the use of motorized

equipment to maintain these facilities.

In 1991, about 14,000 animal-unit-months of grazing

were permitted in Northern Region wilderness. Only

six wildernesses had significant amounts of grazing

(Absaroka-Beartooth, Gospel Hump, Lee Metcalf,

Gates of the Mountains, Hells Canyon, and AnacondaPintlar). Given the limited grazing, significance ratings

for grazing impacts were moderate on a regionwide

basis (fig. 5). For individual wildernesses with livestock grazing, ratings would be much higher. Most

attributes—other than air and, perhaps, animals and

cultural resources—are significantly affected by grazing, where it occurs. For example, the vegetation of

most Northern Region wilderness evolved without

much grazing pressure from large ungulates. Consequently, much of the vegetation (such as perennial

bunchgrasses) is intolerant of heavy and repeated

defoliation.

Figure 5—The significance of livestock grazing impacts on each wilderness attribute and

knowledge about the impacts. Attributes on

the diagonal line of equal significance and

knowledge ratings are the ones most in need

of further research.

Our knowledge about the effects of grazing is substantial, but virtually no studies have been conducted

in wilderness. Additional knowledge is needed most

for impacts to ecosystems/landscapes, wilderness experience opportunities, and animals. Wilderness management could profit greatly from the application of

range management experience to the unique characteristics of wilderness.

Impacts of Mining

About 1,200 mining claims have been recorded in

12 Northern Region wildernesses. So far, however,

claims have been validated only in the Cabinet Mountains Wilderness, where two mines are in the permitting stage. Past and present impacts, therefore, have

been highly localized. The future is less clear, depending on the number of recorded claims determined to be

valid and the type of operation used at each valid claim.

Impacts can be substantial in the localized areas where

mining activity reaches the exploration phase. They

can be severe where development and production occur.

Moreover, valid claims are real property that convey

rights of access and can become private inholdings.

The impacts of mining can be the most intense impacts in wilderness. Vegetation and soils are likely to

be highly disturbed at the mine site, and aquatic systems can be altered by acid drainage from mines or

by chemicals used in the mining process, such as nitrates. However, in the Northern Region, mining impacts are now the most geographically localized of all

significant threats to wilderness. Given this localized

impact, the most significant impacts are likely to be

to aquatic systems (fig. 6), because these impacts can

extend long distances from the source of disturbance.

Our knowledge about mining effects is substantial,

particularly regarding impacts to soils and aquatic

systems. Additional knowledge is needed most for

impacts to ecosystems/landscapes, animals, and wilderness experience opportunities.

Impacts of Fire and Its Management

Fire is an important natural component of most wilderness ecosystems (Wright and Bailey 1982). Suppression of natural fire over the past half century

or more has had substantial effects on many of these

wilderness ecosystems (Kilgore and Heinselman 1990).

Suppression of natural fires that ignited within wilderness and of natural fires that would have burned into

wilderness are both of concern. Fire suppression activities generally decrease the frequency of fires and increase their magnitude. Larger, more intense fires will

cause more pronounced nutrient and sediment flushes

through aquatic systems, as well as more catastrophic

changes in vegetation structure and composition,

greater losses of soil organic horizons, and increased

Soils

Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

•

•

•

•

Cultural resources Experiences

Air

Ecosystems/landscapes

Rock/landforms

Vegetation

•

•
8

losses of nitrogen through volatilization. Periods between fires will be characterized by excessive organic

fuel buildup, incomplete decomposition of biomass, and

inhibition of nutrient cycling (Kilgore and Heinselman

1990). In addition, human-caused fires—either ignited in or burning into wilderness—can be considered adverse impacts, as can disturbances caused by

firefighting.

The impacts of altering natural fire regimes are

highly significant because fire plays such a critical role

in the functioning of most ecosystems and because its

effects are so widespread. This assessment suggests

that the most significant impacts of fire and its management in Northern Region wilderness are to soils,

vegetation, ecosystems, and landscapes (fig. 7). Our

knowledge about fire effects is substantial, particularly

regarding impacts to vegetation, soils, animals, aquatic

systems, ecosystems, and landscapes. The greatest discrepancy between significance and knowledge is for impacts to soils, ecosystems/landscapes and wilderness

experience opportunities. Fortunately, research on wilderness fire has received considerable attention in

the past; hopefully, this attention will continue in the

future.

Impacts of Exotic Species Introductions

and Invasions

Many exotic species have been purposely introduced

or have invaded the Northern Rocky Mountains since

European settlement began in earnest in the late 19th

century. A wide variety of exotic species now inhabit

wildernesses, including plants from fungi to vascular

plants, and aquatic and terrestrial vertebrates and

invertebrates. Among the most significant introductions are:

• The white pine blister rust fungus, which is seriously affecting whitebark pine at high elevations

throughout the Northern Region (Hoff and Hagle

1990).

• A wide variety of vascular plants from noxious

weeds like spotted knapweed to forage plants like

timothy (Tyser and Worley 1992).

• Exotic fish like some trout species (Luecke 1990).

The geographic extent of these introductions varies

widely from the broadly distributed white pine blister

rust, to the common but localized vascular plant introductions, to the highly localized fish introductions.

Although fish introductions may originally have been

confined to a few lakes and streams, these introductions may now have altered a substantial proportion

of aquatic systems in wilderness.

The impacts of exotic introductions are less dramatic

in Northern Region wilderness than perhaps in any

other part of the United States, outside of Alaska.

This reflects the harsh climatic conditions of the highelevation mountain wildernesses, their large size, and

the relatively low level of disturbance to surrounding

lands. Nevertheless, some impacts are significant,

Figure 6—The significance of the impacts

of mining on each wilderness attribute and

knowledge about the impacts. Attributes

on the diagonal line of equal significance

and knowledge ratings are the ones most

in need of further research.

Figure 7—The significance of fire-related

impacts on each wilderness attribute and

knowledge about the impacts. Attributes

below the diagonal line of equal significance and knowledge ratings are the

ones most in need of further research.

Soils Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

•

•

•

Experiences

Air

Rock/landforms

Vegetation

•

•

• Ecosystems/

landscapes

Cultural

resources•

Soils

Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

•

•

•

•

Cultural resources

Experiences

Air

Ecosystems/

landscapes

Rock/landforms

Vegetation

•
9

dams that make migration to and from the ocean difficult (Nehlsen and others 1991).

Most of these impacts are highly localized and occur

in only a small number of wildernesses in the Northern

Region. However, where they do occur, these impacts

can be highly significant. They can alter riparian

habitat and impact rare and threatened taxa (such as

certain races of salmonid fish). In other parts of the

country, where headwater streams more commonly

originate outside of wilderness, these impacts are

likely to be much more significant. The most significant impacts of water projects in Northern Region wilderness have probably been to aquatic ecosystems and

to streamside vegetation (fig. 9). Knowledge about

these impacts is substantial, given the significance

of the impacts. Additional knowledge is needed most

for impacts to vegetation and ecosystems/landscapes.

Impacts of Atmospheric Pollutants

Both local and distant sources of atmospheric pollution can affect wilderness when polluted air enters wilderness. Even though Northern Region wildernesses

are far from major pollution sources, they lie downwind

of major industrialized and urban areas along the Pacific coast. Important pollutants include sulfur oxides

(emitted during combustion of fossil fuels, smelting of

ores, manufacturing of steel, and refining of petroleum),

nitrogen oxides (emitted during combustion, primarily by vehicles), and volatile organic compounds (also

emitted primarily by vehicles). Secondary pollutants,

particularly to aquatic systems and vegetation (fig. 8),

and introductions could easily increase in the future.

Our knowledge about exotic introductions is meager,

except for the impacts of exotic plants on vegetation;

even here, much more needs to be learned. The greatest discrepancy between significance and knowledge is

for impacts to aquatic systems, ecosystems/landscapes,

and animals.

Impacts of Water Projects

Wilderness conditions are affected by dams and

water diversions within three wildernesses—the

Selway-Bitterroot, Absaroka-Beartooth, and Rattlesnake. These dams raise the level of lakes and keep

those levels more constant. They also diminish peak

stream flows in early summer and prolong moderate

flows through the summer. Of more significance is the

effect of upstream dams and water diversions along the

Snake River in the Hells Canyon Wilderness. Water

projects can alter a stream’s water temperatures, sediment loads, and chemical and biological characteristics as well as adjacent soils and vegetation (Ward and

Sanford 1987). The headwaters of the Salmon River,

which flows through the Frank Church-River of No

Return and Gospel Hump Wildernesses are also outside of the wildernesses. These upstream waters are

used extensively for irrigation, but there are no major

water impoundments. Pollution of upstream waters can

also affect wildernesses. Finally, all wildernesses that

contain anadromous fish are affected by downstream

Figure 8—The significance of impacts caused

by exotic species introductions on each wilderness attribute and knowledge about the impacts. Attributes below the diagonal line of

equal significance and knowledge ratings are

the ones most in need of further research.

Figure 9—The significance of impacts caused

by water projects on each wilderness attribute

and knowledge about the impacts. Attributes

on the diagonal line of equal significance and

knowledge ratings are the ones most in need

of further research.

Soils

Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

• •

•

Experiences

Air

Rock/landforms

Vegetation •

•

Ecosystems/landscapes

Cultural resources

Soils

Animals Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

•

•

•

Experiences

Air

Rock/landforms

Vegetation

•

•

Ecosystems/landscapes

Cultural resources

•
10

such as ozone and fine particulate matter, form when

primary pollutants are transformed in the atmosphere. Pollutants can be transferred to the ground

by dry and wet deposition, as well as by contact with

low-lying clouds.

The potential impacts of atmospheric pollutants are

great because they are so broadly dispersed and capable of altering the most basic functions of ecosystems

(Schreiber and Newman 1987). Impacts include reductions in visibility and inputs to aquatic systems that

change water chemistry, affecting the aquatic biota.

Deposition on plants can injure them directly, but the

most pervasive impacts might be the indirect effects

of pollutants on soils, such as reduced nutrient availability, increased solubility of toxic metals, and reduced

mycorrhizal development (Grigal 1988).

Northern Region wildernesses are less severely impacted than wildernesses in other parts of the country because there are relatively few significant local

sources of pollution. Nonetheless, impacts to air, soils,

vegetation, aquatic systems, and ecosystems/landscapes

can be quite significant (fig. 10). Fortunately, the effects of air pollution have been studied extensively, and

a number of studies have begun in wilderness. The

greatest discrepancy between significance and knowledge is for impacts to ecosystems/landscapes, soils, and

vegetation.

Impacts of Practices on Adjacent Lands

Practices on adjacent lands that affect wilderness

include several threats that have already been discussed, such as emission of atmospheric pollutants,

water projects, and fire management. Other activities on adjacent lands that can cause impacts include

timber cutting, road construction, and urban development. These can pollute downstream waters, introduce

exotic species, and adversely affect migratory animals

(Glenn and Nudds 1989). These impacts can be particularly severe in wildernesses downstream from developed lands (Hells Canyon, Selway-Bitterroot, Frank

Church-River of No Return, and Gospel Hump), as

well as those that are relatively small. Although the

Northern Region contains several of the largest blocks

of wilderness in the United States, six wildernesses

are smaller than 100,000 acres, or are fragmented with

the fragments smaller than 100,000 acres. For these

smaller wildernesses, particularly, wilderness must

be managed as part of a larger landscape (Harris 1984).

Fragmentation and development of the larger landscape affects large-scale ecological processes, flows

of energy and materials, and disturbance regimes

(Schonewald-Cox and Buechner 1992).

The impacts of practices on adjacent lands are quite

substantial, particularly to animals, ecosystems/

landscapes, and wilderness experiences (fig. 11). These

external impacts are probably less severe in Northern

Figure 11—The significance of impacts caused

by practices on adjacent lands on each wilderness attribute and knowledge about the impacts. Attributes below the diagonal line of

equal significance and knowledge ratings are

the ones most in need of further research.

Region wilderness than anywhere else in the United

States outside of Alaska. This reflects the relative

lack of development and low population in the Northern Rockies. In other parts of the country, these external impacts are likely to be much more significant.

Figure 10—The significance of impacts caused

by atmospheric pollutants on each wilderness

attribute and knowledge about the impacts.

Attributes below the diagonal line of equal significance and knowledge ratings are the ones

most in need of further research.

Soils

Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

• •

•

Experiences

Air

Rock/landforms

Vegetation

•

•

Ecosystems/

landscapes

Cultural resources

•

Soils Animals

Aquatics

5

4

3

2

1

1 2 3 4 5

Significance

Knowledge

• •

•

Experiences

Air

Rock/landforms

Vegetation • •

Ecosystems/

landscapes

Cultural resources

•

•
11

Our knowledge about impacts of practices on adjacent

lands is sparse, particularly for impacts to ecosystems/

landscapes, wilderness experiences, and to a lesser

extent, animals. More research on these impacts is

clearly needed.

Significance of Threats to Northern

Region Wilderness

This analysis identifies those threats to Northern

Region wilderness that are considered to be most significant and the wilderness attributes that are considered to be most threatened (fig. 12). This knowledge

can help set regional priorities for wilderness management. The significance of each potential threat depends on the wilderness attribute being considered.

For example, recreational use is a significant threat

to wilderness experience opportunities but has little

effect on air. Each potential threat is the most significant threat to at least one attribute. Fire and its management was considered the most significant threat to

five of the nine attributes, while livestock grazing,

water projects, and exotic species each were the most

significant threat to only one attribute.

The mean significance rating, across all attributes

(table 1), was greatest for fire and its management

(3.4). This can be considered the most significant

threat to the preservation of wilderness character

in the Northern Region. Other threats with high mean

significance ratings (2.7 to 2.9) were atmospheric pollutants, recreation, and practices on adjacent lands.

Even threats with lower ratings—such as livestock

grazing, exotic species introductions, mining, and water projects—have the potential to substantially impact wilderness; however, they are relatively limited

in Northern Region wilderness. Livestock grazing

would be a more significant threat in the southwestern United States, while exotic species introductions

would be more significant in the southeastern United

States. Threats from atmospheric pollutants and practices on adjacent lands would be more significant in

the eastern United States, where wildernesses are typically small and close to urban areas. Water projects

are likely to be a more significant threat in proposed

Bureau of Land Management wildernesses, which

typically do not contain headwaters.

Differences in significance among threats to attributes are greater than differences among the threats

themselves. Seven of the nine wilderness attributes

were considered the attribute most significantly impacted by at least one potential threat. Geological

and cultural features were not the most significantly

impacted attribute for any threat. Aquatic systems

was considered the attribute most threatened by six

different threats, and vegetation was considered the

attribute most threatened by five different threats.

Potential Threats

Recreation

Adjacent

Other

lands

Atmospheric

pollutants

Water

projects

Exotic

species

Mining

Fire

Livestock

Air

Aquatic

systems

Rock/

landforms

Soils

Vegetation

Animals

Ecosystems/

landscapes

Cultural

resources

Wilderness

Attributes of Wilderness Character

experiences

1 11 2 11 43

4 33 4 43 43

1 22 1 12 11

3 32 5 22 42

3 32 5 43 42

4 22 4 32 24

2 32 5 32 45

3 22 2 11 11

4 32 3 22 23

Figure 12—Significance ratings for the impacts of each potential threat on each wilderness attribute, for wildernesses in the Forest Service’s Northern Region. Ratings range

from 1 (low) to 5 (high).
12

The mean significance rating for wilderness attributes, considering all threats (table 2), was greatest

for aquatic systems (3.5). If aquatic systems are the

most threatened of wilderness attributes, an immediate shift in priorities is needed. Most attention is being given to management of terrestrial systems in wilderness. Vegetation and ecosystems/landscapes also

had high significance ratings of 3.3.

Research Gaps Concerning Threats

to Northern Region Wilderness

By comparing significance and knowledge ratings,

relative priorities can be assigned to each impact concerning the need for further research (fig. 13). I assigned a low priority to impacts with significance ratings of 2 or less, regardless of knowledge levels. I

assigned moderate priority to those impacts with

Table 1—Significance of and knowledge about eight potential threats to wilderness in the Northern

Region1

Significance Knowledge Research gap

Threat rating rating index

Fire 3.4 3.5 3.0

Atmospheric pollutants 2.9 3.1 2.8

Recreation 2.8 3.1 2.8

Practices on adjacent lands 2.7 2.9 2.8

Livestock Grazing 2.4 3.5 2.1

Exotic species 2.3 2.5 2.6

Mineral activities 2.1 2.9 1.4

Water projects 2.0 3.1 1.4

1

Ratings are between 1 (low) and 5 (high) and are mean ratings for the nine individual wilderness attributes. Impacts

given a significance rating of 1 were excluded from the mean knowledge ratings. The research gap index is the mean

research priority rating, between 1 (low) and 5 (high) for the nine attributes.

significance ratings of at least 3 and knowledge ratings

at least as high as their significance ratings. Finally,

I assigned high priority to impacts with significance

ratings of at least 3 and knowledge ratings lower than

their significance ratings. Of the 72 impacts (cells in

the matrix), 37 (51 percent) are low priority, 21 (29 percent) are moderate priority, and 14 (19 percent) are

high priority. While the high-priority impacts are in

most immediate need of further research, all of the

moderate-priority impacts and many of the low-priority

impacts also need further study.

To extend this analysis to general conclusions about

the relative priority of individual threats and attributes,

I calculated a research gap index. I assigned values of

1 (low priority), 3 (moderate priority), or 5 (high priority) to each cell in the matrix. The research gap index

is simply the mean of these rankings across all threats

or across all attributes. This analysis suggests that

Table 2—Significance of and knowledge about threats to nine attributes of wilderness in the Northern

Region1

Significance Knowledge Research gap

Threat rating rating index

Aquatic systems 3.5 3.5 3.5

Ecosystems/landscapes 3.3 2.4 3.3

Vegetation 3.3 3.8 2.8

Soils 2.9 3.5 2.5

Animals 2.9 2.6 2.8

Wilderness experiences 2.8 2.9 2.8

Air 1.8 3.7 1.5

Cultural resources 1.6 2.8 1.3

Rock/landforms 1.4 3.0 1.0

1

Ratings are between 1 (low) and 5 (high) and are mean ratings for eight potential threats. Impacts given a significance rating of 1 were excluded from the mean knowledge ratings. The research gap index is the mean research priority rating, between 1 (low) and 5 (high) for the eight threats.
13

L L L LL LMM

H M M MH MM M

L L L LL LL L

M M L HL L H L

M M L MM MH L

H L L MH L L H

L M L HH L H H

ML L LL LL L

M M M HL L L H

Potential Threats

Recreation

Adjacent

Other

lands

Atmospheric

pollutants

Water

projects

Exotic

species

Mining

Fire

Livestock

Air

Aquatic

systems

Rock/

landforms

Soils

Vegetation

Animals

Ecosystems/

landscapes

Cultural

resources

Wilderness

Attributes of Wilderness Character

experiences

Figure 13—Research priorities for the impacts of each threat on each wilderness attribute, for wilderness in the Forest Service’s Northern Region. Low-priority impacts had a significance rating of

2 or less, regardless of knowledge. Medium-priority impacts had a significance rating of at least 3

and a knowledge rating at least as high as its significance rating. High-priority impacts had a significance rating of at least 3 and a knowledge rating lower than the significance rating.

fire and its management is the potential threat most

in need of further research in the Northern Region

(table 1). Threats with moderately large research gaps

are exotic species introductions, practices on adjacent

lands, atmospheric pollutants, and recreation. Threats

that are the lowest priorities for further research in

the Northern Region are mineral activities, livestock

grazing, and water projects.

The attributes most in need of further study are

aquatic systems and ecosystems/landscapes (table 2).

Attributes with moderately large research gaps are

wilderness experience opportunities, animals, vegetation, and soils. The attributes that are the lowest priorities for further research in the Northern Region are

cultural resources, rock/landforms, and air. Again,

even these lowest priorities are so poorly understood

that more research is warranted.

CONCLUSIONS

This matrix of potential threats to attributes of wilderness character can be a useful tool to wilderness

managers. It can be used to evaluate the significance

of threats to wilderness and to set management priorities. It can be used to identify critical research gaps.

It also can be used to identify the types of impacts

that need to be monitored. These priorities can be assessed either for individual wildernesses or for larger

regions.

In Northern Region wilderness, the most significant

threat to wilderness character is the suppression of

natural fire. The most threatened wilderness attribute is aquatic systems. The most critical research

needs would appear to be research on fire, aquatic systems, and ecosystems and landscape patterns and processes. In other parts of the country and in wilderness

managed by other agencies, other threats and attributes will be more important and in more need of study.

Each region would profit from assessing threats to wilderness in the manner reported here.

The conclusions reported here are the collective informed judgments of a group of regional experts. The

uncertainty of these conclusions reflects the inadequate

attention given to wilderness threats and the lack of

extensive data. The threats matrix is a conceptual

framework that forces us to take a more comprehensive perspective than we have typically taken. This

is merely the first step toward a more comprehensive

view of wilderness management. That view will be

necessary if we are to approach the lofty goals established by the Wilderness Act.
14

REFERENCES

Cole, David N. 1987. Research on soil and vegetation

in wilderness: a state-of-knowledge review. In: Lucas,

Robert C., comp. Proceedings—national wilderness

research conference: issues, state-of-knowledge, future directions; 1985 July 23-26; Fort Collins, CO.

Gen. Tech. Rep. INT-220. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain

Research Station: 135-177.

Cole, David; Landres, Peter; Watson, Alan. 1993. A

strategy for improving wilderness monitoring. Unpublished paper on file at: U.S. Department of Agriculture, Forest Service, Aldo Leopold Wilderness

Research Institute, Missoula, MT. 14 p.

Glenn, Susan M.; Nudds, Tom D. 1989. Insular biogeography of mammals in Canadian parks. Journal of

Biogeography. 16: 261-268.

Grigal, D. F. 1988. Long-range impacts of air pollution

on terrestrial resources. In: Agee, James K.; Johnson,

Darryll R., eds. Ecosystem management for parks and

wilderness. Seattle, WA: University of Washington

Press: 118-134.

Hammitt, William E.; Cole, David N. 1987. Wildland

recreation: ecology and management. New York:

John Wiley and Sons. 341 p.

Harris, Larry D. 1984. The fragmented forest: island

biogeographic theory and the preservation of biotic

diversity. Chicago, IL: University of Chicago Press.

211 p.

Hoff, Ray; Hagle, Susan. 1990. Diseases of whitebark

pine with special emphasis on white pine blister rust.

In: Schmidt, Wyman C.; McDonald, Kathy J., comps.

Proceedings—symposium on whitebark pine ecosystems: ecology and management of a high-mountain

resource; 1989 March 29-31; Bozeman, MT. Gen.

Tech. Rep. INT-270. Ogden, UT: U.S. Department

of Agriculture, Forest Service, Intermountain Research Station: 179-190.

Kilgore, Bruce M.; Heinselman, Miron L. 1990. Fire in

wilderness ecosystems. In: Hendee, John C.; Stankey,

George H.; Lucas, Robert C. Wilderness management.

2d ed. Golden, CO: Fulcrum Publishing: 297-335.

Kuss, Fred R.; Graefe, Alan R.; Vaske, Jerry J. 1990.

Visitor impact management: a review of research.

Washington, DC: National Parks and Conservation

Association.

Luecke, Chris. 1990. Changes in abundance and distribution of benthic macroinvertebrates after introduction of cutthroat trout into a previously fishless

lake. Transactions of the American Fisheries Society.

119: 1010-1021.

Machlis, G. E.; Tichnell, D. L. 1985. The state of the

world’s parks. Boulder, CO: Westview Press. 131 p.

Manning, Robert E. 1985. Studies in outdoor recreation: search and research for satisfaction. Corvallis,

OR: Oregon State University Press. 166 p.

Nehlsen, W.; Williams, J. E.; Lichatowich, J. A. 1991.

Pacific salmon at the crossroads: stocks at risk from

California, Oregon, Idaho, and Washington. Fisheries. 16(2): 4-21.

Platts, William S. 1981. Effects of sheep grazing on a

riparian-stream environment. Res. Note INT-307.

Ogden, UT: U.S. Department of Agriculture, Forest

Service, Intermountain Forest and Range Experiment Station. 5 p.

Schonewald-Cox, Christine; Buechner, Marybeth.

1992. Park protection and public roads. In: Fiedler,

Peggy L.; Jain, Subodh K., eds. Conservation biology:

the theory and practice of nature conservation, preservation, and management. New York: Chapman

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37 p.

Tyser, Robin W.; Worley, Christopher A. 1992. Alien

flora in grasslands adjacent to road and trail corridors in Glacier National Park, Montana (U.S.A.).

Conservation Biology. 6: 253-262.

Vallentine, John F. 1990. Grazing management.

San Diego, CA: Academic Press. 533 p.

Ward, J. V.; Sanford, J. A. 1987. The ecology of regulated streams: past accomplishments and directions

for future research. In: Craig, J. F.; Kemper, J. B.,

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John Wiley and Sons. 501 p.
Cole, David N. 1994. The wilderness threats matrix: a framework for assessing impacts.

Res. Pap. INT-475. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 14 p.

A comprehensive framework for assessing threats to wilderness is described. The framework is represented as a matrix of potential threats and attributes of wilderness character.

Cells in the matrix represent the impacts of threats on each attribute. Potential applications

of the matrix are described. An application of the matrix to the wildernesses in the Forest

Service’s Northern Region (northern Idaho and Montana) suggests that fire management

is the most significant threat to those wildernesses and that aquatic systems are the most

threatened wilderness attribute.

KEYWORDS: impacts, monitoring, assessment, Idaho, Montana

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The Intermountain Research Station provides scientific knowledge and technology to improve management, protection, and use of the forests and rangelands of the Intermountain

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State agencies, industry, academic institutions, public and private organizations, and individuals. Results of research are made available through publications, symposia, workshops,

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The Intermountain Research Station territory includes Montana, Idaho, Utah, Nevada, and

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Several Station units conduct research in additional western States, or have missions that

are national or international in scope.

Station laboratories are located in:

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Logan, Utah (in cooperation with Utah State University)

Missoula, Montana (in cooperation with the University of Montana)

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