USDA United States =/ 

- Department of Agriculture 

Forest Service 

Rocky Mountain 

Research Station 

Research Paper 

RMRS-RP-16 

February 1999 

Competitive Effects of 

Bluebunch Wheatgrass, Crested 

Wheatgrass, and Cheatgrass on 

Antelope Bitterbrush Seedling 

Emergence and Survival 

Derek B. Hall 

Val Jo Anderson 

Stephen B. Monsen 

This file was created by scanning the printed publication.

Errors identified by the software have been corrected;

however, some errors may remain.
Abstract 

Hall, Derek B.; Anderson, Val Jo; Monsen, Stephen B. 1999. Competitive effects of bluebunch wheatgrass, crested 

wheatgrass, and cheatgrass on antelope bitterbrush seedling emergence and survival. Res. Pap. RMRS-RP-16. Ogden, 

UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 7 p. 

The competitive environment into which plant seedlings emerge often determines the survival and performance of these 

individuals. This study was designed to determine the effects of bluebunch wheatgrass (Pseudoroegneria spicata), crested 

wheatgrass (Agropyron cristatum), and cheatgrass (Bromus tectorum) on soil moisture depletion, associated antelope 

bitterbrush (Purshia tridentata) seedling emergence, xylem pressure potential, and subsequent survival. In the fall of 1992, 

antelope bitterbrush seed was sown into the following four established competitive matrices: (1) bluebunch wheatgrass, (2) 

crested wheatgrass, (3) cheatgrass, and (4) bare soil control plots. Soil moisture and bitterbrush seedling xylem pressure 

potential data were collected through the spring and summer of 1993. Antelope bitterbrush seedling survival data were 

collected through the spring and summer of 1993, and again in July 1994. Invasion of bur buttercup (Ranunculus testiculatus) 

in the spring of 1993 increased the competitive environments with densities of 470 plants per m2 in the crested wheatgrass, 

760 in bluebunch wheatgrass, 920 in control and 1,060 in cheatgrass plots. Soil moisture in crested wheatgrass plots tended 

to be lower than soil moisture in the bluebunch wheatgrass plots. The number of emerged bitterbrush seedlings were 

significantly (? = 0.99) negatively correlated with the number of total annuals per m2. Antelope bitterbrush seedling xylem 

pressure potentials were less negative in the bluebunch wheatgrass plots compared with the other plots. Percent antelope 

bitterbrush seedling survival over 2 years was significantly higher (nearly twice) when grown in association with bluebunch 

wheatgrass than seedlings grown in association with crested wheatgrass, cheatgrass, or bur buttercup. 

Keywords: Pseudoroegneria spicata, Agropyron cristatum, Bromus tectorum, Purshia tridentata, Rununculus testiculatus, 

xylem pressure potential, soil moisture, rangeland restoration 

The Authors 

Derek B. Hall is a Scientist with Bechtel Nevada, PO Box 

98521, Las Vegas, NV 891 93-8521. His degrees are from 

Brigham Young University (B.S. in wildlife and range resources, 1992; and M.S. in wildlife and range resources, 1994). 

At the time of the research, he was a Research Assistant in the 

Botany and Range Science Department, Brigham Young University, and concurrently a Biological Technician (1992 to 

1994) for the Shrubland Biology and Restoration Research 

Work Unit at the Intermountain (now Rocky Mountain) Research Station's Shrub Sciences Laboratory in Provo, UT. 

Val Jo Anderson is an Associate Professor in the Botany and 

Range Science Department at Brigham Young University, 

Provo, UT 84602. His degrees are from Snow College (A.S. in 

science, 1980), Utah State University (B.S., 1982 and M.S., 

1985 in range science) and Texas A&M University (Ph.D. in 

rangeland ecology, 1989). He joined the faculty at Brigham 

Young University in 1988 and teaches undergraduate and 

graduate classes including range and pasture plant ecology, 

rangeland inventories and analysis, Natural Resource Planning, and Agrostology. He has completed research in Morocco, 

Australia, and throughout the Western United States, focused 

on the impacts to rangelands of land management practices 

and restoration of degraded rangelands. 

Stephen B. Monsen is a Botanist for the Shrubland Biology 

and Restoration Research Work Unit at the Rocky Mountain 

(formerly, Intermountain) Research Station's Shrub Sciences 

Laboratory in Provo, UT 84606. His degree is from Brigham 

Young University (B.S. in agronomy, 1958). He also has 

graduate training at Brigham Young University (1 958 to 1960) 

in botany and range science. He began his Forest Service 

research career in 1958 and has worked at the Forestry 

Sciences Laboratory in Boise, and since 1983 at the Shrub 

Sciences Laboratory. From 1959 to 1969 he worked as a 

researcher for the Utah Division of Wildlife Resources in 

Ephraim, Utah. His research has emphasized wildland 

restoration in the Western United States and Australia. 

Rocky Mountain Research Station 

324 25th Street 

Ogden, UT 84401 
Competitive Effects of 

Bluebunch Wheatgrass, Crested 

Wheatgrass, and Cheatgrass on 

Antelope Bitterbrush Seedling 

Emergence and Survival 

Derek 9. Hall 

Val Jo Anderson 

Stephen B. Monsen 

Introduction 

Shrubs dominate many plant communities throughout the Western United States, particularly in the 

Great Basin. McGinnies (1972) suggested that the 

northern desert shrub type is among the most important shrub community in North America. Shantz and 

Zon (1924) recognized three main associations in the 

sagebrush or northern desert shrub type. Among 

these is the big sagebrush (Artemisia tridentata Nutt.) 

association including communities dominated by big 

sagebrush, rubber rabbitbrush (Chrysothamnus nauseosus Britt.), and antelope bitterbrush (Purshia tridentata Pursh.), among others. 

These communities, consisting of a variety of small 

to large shrubs that form an open canopy, support a 

grass/forb understory. Shrub-dominated communities 

provide crucial winter and spring habitat for wild 

ungulates, particularly mule deer and elk, as well as 

cattle and sheep (McKell and Goodin 1973; Plummer 

1972). High energy content of dry grass culms coupled 

with high protein levels found in the current year twig 

growth of shrubs provide excellent winter and spring 

forage (Cook 1972). 

Relatively constant and heavy use by wild and 

domestic ungulates has created changes in species 

composition of both woody and herbaceous components of many communities. Cheatgrass (Bromus tectorum Linn.) and other annual weeds have invaded 

and dominate many areas within brush communities 

where native plant species have been weakened 

(Vallentine 1989). Crested wheatgrass (Agropyron 

cristatum Linn.) has been seeded onto millions of acres 

of rangeland throughout the Western United States to 

stabilize herbage production, protect watersheds, and 

control weeds (Holechek 1981). Crested wheatgrass 

persists under heavy grazing pressure relative to 

many native counterparts and has been seeded into 

weakened native plant communities. 

These introduced annual and perennial grass species appear to affect native shrub recruitment and 

subsequent community composition. Several studies 

have shown that competition from introduced grasses 

restricts either shrub seedling emergence or establishment or both. Hormay (1943a,b) reported that 

cheatgrass retarded natural establishment of antelope bitterbrush. Holmgren (1956) concluded that few 

antelope bitterbrush seedlings were able to survive 

the first summer in cheatgrass stands. Monsen and 

Shaw (1983) suggested that established stands of 

desert wheatgrass (Agropyron desertorurn Linn.), a 

close relative of crested wheatgrass, limited the natural regeneration of antelope bitterbrush. Price and 

Brotherson (1987) partially attributed low recruitment rates in stands of Stansbury cliffrose (Cowania 

mexicana stansburiana Torr.) to competition from 

annual grasses. Melgoza and others (1990) determined that cheatgrass competes with needle-andthread grass (Stipa comata Trin. & Rupr.) and Douglas rabbitbrush (Chrysothamnus viscidiflorus Nutt.) 

for soil water and negatively affects their water status 

and productivity. Eissenstat and Caldwell(1988) reported that sagebrush indicator plants had lower 

survival, growth, reproduction, and late-season water 

potential in areas dominated by desert wheatgrass in 

contrast to areas dominated by bluebunch wheatgrass 

(Pseudoroegneria spicata [Pursh.] Love). 

Native grass understories may also negatively impact shrub seedling survival (Eissenstat and Caldwell 

1988; Hubbard 1959). However, introduced annual 

and perennial grasses, namely, desert wheatgrass, 

crested wheatgrass, and cheatgrass utilize soil moisture earlier in the growing season than the native 

bluebunch wheatgrass because of their rooting characteristics (Aguirre and Johnson 1991; Caldwell and 

Richards 1986; Harris 1967; Harris 1977; Harris and 

Wilson 1970). The ability of these introduced grasses 

to utilize soil moisture earlier in the growing season 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
than bluebunch wheatgrass gives them a competitive 

advantage over bluebunch wheatgrass and quite possibly, over other native species as well. Although 

bluebunch wheatgrass competes with shrub seedlings, 

it may not have as detrimental effect on shrub seedling survival as the introduced species (Eissenstat and 

Caldwell 1988). Few studies have focused on the 

influence of competitive herbs on shrub seed germination and emergence, but it seems apparent that 

there is an effect on seedling recruitment. 

This study was designed to determine the effect of 

various understory species, namely, cheatgrass, 

'Hycrest' crested wheatgrass, and 'Goldar' bluebunch 

wheatgrass on (1) soil moisture depletion in the top 

114 cm of the soil profile, (2) the xylem pressure potential of antelope bitterbrush seedlings, and (3) the 

emergence and subsequent survival of antelope bitterbrush seedlings. The hypothesis tested was that shrub 

seedling emergence and subsequent survival are lower 

in areas dominated by the introduced grass species 

(cheatgrass and crested wheatgrass) than bluebunch 

wheatgrass. 

Materials and Methods 

Study Area 

The study area is located 4.5 km south of Nephi, UT, 

at an elevation of 1,385 m. Soil at the site is classified 

as a Nephi silt loam. This soil is a fine-silty, mixed, 

mesic Calcic Argixeroll with a soil pH of approximately 8.3. Average annual precipitation is 356 to 

406 mm, mean annual air temperature is 7 to 11 "C, 

and the average frost-free season is 100 to 140 days. 

The study site originally supported a mixed shrub and 

bunch grass community consisting of basin big sagebrush Arternisia tridentata Nutt. sp. tridentata, antelope bitterbrush, rubber rabbitbrush, and blue bunch 

wheatgrass. The site has been used to conduct dryland cropping and community restoration research for 

over 50 years. 

Competitive Matrices 

Twenty-four competitive matrix plots, consisting of 

eight replicate plots of each of the three grass species 

(Goldar bluebunch wheatgrass, Hycrest crested wheatgrass, and cheatgrass), and four bare ground control 

plots were established. The two wheatgrass species 

were greenhouse propagated and transplanted to the 

study site in the fall of 1991. At the time of transplanting, plants were approximately 6 months old. 

Goldar bluebunch wheatgrass is a cultivar native to 

the Palouse prairie of northern Idaho. Hycrest is a 

cultivar of crested wheatgrass and is commonly seeded 

on western rangelands. Transplants were placed at 

0.5 m spacings in 9 m2 matrices with 49 plants in each 

matrix. The transplants were watered periodically 

through the first growing season to ensure the establishment of a uniform and strong competitive matrix. 

Cheatgrass seed was collected near the study site 

and seeded in rows spaced 20 cm apart in the fall of 

1992. 

During the summer of 1992, a rodent-proof fence 

was erected around the site to keep rodents from eating 

the shrub seeds. The site was also weeded several 

times during the summer in an attempt to reduce the 

confounding effects of weeds in the experiment. 

In the fall of 1992, four 25 seed caches (74 percent 

viability) of antelope bitterbrush were sown into each 

of four 0.25 m interspaces (yielding 400 seeds per 

matrix) in the interior of each competitive matrix and 

each control plot. In addition, aluminum tubes were 

implanted to a depth of about 114 cm in the outer row 

of half of the competitive matrices to provide access 

for a neutron probe for soil moisture measurements. 

Soil moisture, xylem pressure potential, and densities of antelope bitterbrush seedlings were measured 

and recorded at seven dates through the spring and 

summer of 1993: April 29, May 13, May 20, May 27, 

June 4, June 25, and August 2. In addition, bitterbrush seedling densities were recorded again in July 

1994 to determine percent survival. Soil moisture 

was measured gravimetrically in the top 22 cm and 

with aneutron probe (California Pacific Nuclear Model 

503DR) in the lower profile (22 to 114 cm). Soil moisture was reported as percent by volume. 

Predawn xylem pressure potentials were measured 

with a Scholander type pressure bomb (Waring and 

Cleary 1967). At each sampling date, one shrub seedling was harvested and measured from each matrix to 

determine xylem pressure potential. Additionally, the 

youngest fully expanded leaf of three randomly selected tillers of the competing species in each matrix 

were used to determine the xylem pressure potential 

of the competitors. At each sampling date seedlings 

were counted in each interspace (numbers of living 

and dead seedlings were recorded separately and dead 

seedlings were then removed). 

In late May, one-half of all the competitive matrices 

for each species were defoliated by removal of 80 

percent of the foliage to simulate heavy spring use by 

ungulates. A heightlweight relationship procedure 

was used to determine the defoliation height for various utilization levels. Biomass was also measured by 

weighing the clipped material and then determining 

its dry weight. Bur buttercup (Ranunculus testiculatus Crantz), other weedy species, and cheatgrass densities were measured along with height and basal 

circumference of wheatgrass species to quantify the 

competitive matrices. 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
The two-factor factorial design (four levels of competitive matrices by two levels of matrix defoliation) 

was analyzed using the Number Cruncher Statistical 

System (NCSS) general linear models procedure to 

determine the response differences in antelope bitterbrush emergence and survival as well as soil moisture 

and xylem pressure potential differences between 

treatments (NCSS 1989). Mean separations were conducted using a protected Fisher's Least Significant 

Differences procedure at the p-values indicated for 

each parameter (all P < 0.10). 

Results and Discussion 

Competitive Matrices 

When data were collected in the spring of 1993, the 

average bunchgrass was approximately 50 cm in circumference and cheatgrass densities averaged 914 

plants per m2 in the cheatgrass plots. Biomass in the 

grass plots was regressed against percent survival at 

the date of defoliation (May 20). There was no significant relationship between these two variables. 

Although the site was weeded several times the 

previous summer, bur buttercup seed persisted in 

the soil and germinated the following spring. Bur 

buttercup densities averaged 1,060 plants per m2 in 

cheatgrass, 920 in control, 760 in bluebunch wheatgrass, and 470 plants in crested wheatgrass matrices. 

The high bur buttercup densities in the cheatgrass 

plots, combined with the cheatgrass, formed an annual competitive matrix rather than a simple 

cheatgrass competitive matrix. Control plots also had 

high bur buttercup densities which likely influenced 

soil moisture, antelope bitterbrush seedling xylem 

potential, and antelope bitterbrush seedling survival. 

Bur buttercup densities were significantly higher in 

bluebunch wheatgrass matrices than in crested wheatgrass matrices, suggesting that crested wheatgrass is 

a stronger competitor than bluebunch wheatgrass. 

Soil Moisture 

Results from the soil moisture analysis showed 

that defoliation had no significant effect on soil moisture or subsequent xylem pressure potential readings 

of associated antelope bitterbrush seedlings. This 

was unexpected, but may be explained by the unusually high frequency and intensity of rainfall experienced throughout the spring and early summer of 

1993. 

The two-way interaction for soil moisture between 

date and depth was significant (fig. 1). This indicates 

Soil Depth (cm) 

V? MaV 20,93 

May 27,93 

hW,Y June 4, 93 - June 25, 93 

August 2, 93 

Figure 1-Percent soil moisture by volume at five depths through the spring 

and summer of 1993 (interaction, p < 0.01). 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
that soil moisture in the upper portions of the soil 

profile was depleted more rapidly, and fluctuated 

significantly in response to pulses of precipitation. 

Cline and others (1977) also determined that water 

loss was especially rapid in surface soil layers and less 

rapid deep in the soil profile. Soil moisture in the upper 

part of the soil profile is critical to establishing shrub 

seedlings, particularly early in the growing season. 

The soil profile exhibited an expected, yet somewhat 

retarded depletion curve for moisture through the 

summer. The competitive matrix by soil depth interaction for soil moisture was also significant (fig. 2). Soil 

moisture in the crested wheatgrass matrices was consistently lower than in the bluebunch wheatgrass or 

cheatgrass matrices in the top 84 cm. This is consistent with our hypothesis as well as the findings of 

Eissenstat and Caldwell (1988). They reported that 

desert wheatgrass depleted more moisture from the 

soil profile than did bluebunch wheatgrass. Soil moisture in the bluebunch wheatgrass and cheatgrass 

plots did not significantly differ from each other averaged across season, although soil moisture values 

were consistently higher in bluebunch wheatgrass 

matrices in the upper 53 cm of the soil profile. Below 

53 cm, soil moisture was slightly higher in cheatgrass 

matrices than in bluebunch wheatgrass matrices. 

This is consistent with the findings of Cline and 

others (1977) who concluded that soil water stored 

below 50 cm in a cheatgrass community was not fully 

exploited. The more favorable than expected soil moisture profile for cheatgrass may be explained in part by 

higher than normal precipitation in May and June. 

This may have allowed soil moisture in the cheatgrass 

plots to remain relatively high. A repeat of this experiment during a dry spring would be needed to adequately test the relationship of water use patterns 

between cheatgrass, bluebunch wheatgrass and 

crested wheatgrass. 

Antelope Bitterbrush Seedling Emergence 

In the spring of 1993 there was no significant difference between an average of 156 antelope bitterbrush seedlings emerged in the crested wheatgrass 

Soil Depth (cm) 

I-1 Bluebunch Wheatgrass 

Crested Wheatgrass 

Cheatgrass 

hS\1 Control 

Figure 2-Percent soil moisture at five depthsin the four different competitive matrices 

(interaction, p < 0.01). 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
matrices, and the 148 in bluebunch wheatgrass or 134 

in control matrices. There were significantly (p = 0.08) 

fewer emerged seedlings (93) in the cheatgrass matrices than either the crested wheatgrass or bluebunch 

wheatgrass matrices. When seedling numbers were 

regressed against total annual plant density 

(cheatgrass + annual forbs), a significant negative 

relationship (r2 = 0.99) was revealed. As annual plant 

. density increased, the number of bitterbrush seedlings decreased. 

Grass and Bitterbrush Seedling Xylem 

Potentials 

Xylem pressure potentials of bluebunch wheatgrass 

did not significantly differ from crested wheatgrass, 

although an observed trend showed that bluebunch 

wheatgrass had less negative potentials than crested 

wheatgrass. This suggests that perhaps bluebunch 

wheatgrass is more efficient at using or conserving 

water than is crested wheatgrass, since bluebunch 

wheatgrass used less soil moisture yet had lower 

negative xylem pressure potentials than did crested 

wheatgrass. Bluebunch wheatgrass xylem pressure 

potentials tended to be less negative than cheatgrass 

potentials. 

The two-way interaction between competitive matrix and collection date was significant for antelope 

bitterbrush xylem pressure potentials (fig. 3). Shrub 

seedlings in the bluebunch wheatgrass matrices had 

less negative xylem pressure potentials than seedlings in the other plots. Seedlings in crested wheatgrass plots exhibited the most negative pressure potentials late in the season as soil moisture declined. 

Eissenstat and Caldwell (1988), obtained similar results using desert wheatgrass with Wyoming big 

sagebrush transplants as indicator plants. They found 

that "Arternisia indicator plants had lower survival, 

growth, reproduction, and late-season water potential 

in the neighborhoods dominated by Agropyron desertorurn, than in those dominated by Agropyron spicaturn (bluebunch wheatgrass)." 

April 29, 93 

May 13,93 

May 20,93 

May 27,93 

June 4,93 

June 25,93 

August 2,93 

L 5 -3.0' 

Q Pssp Agcr Brte Control 

Competitive Matrix 

Figure 3-Antelope Bitterbrush seedling xylem pressure potentials in the four different 

competitive matrices through the spring and summer of 1993 (interaction, p < 0.01). 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
Antelope Bitterbrush Seedling Survival 

Antelope bitterbrush seedling survival was not 

significantly different between matrix defoliation 

treatments. Again, higher than normal rainfall in 

May and June may not have allowed the soil to dry out 

sufficiently to show effects from the defoliation treatment, or the treatment was carried out too late in the 

season, so as not to affect the survival of bitterbrush 

seedlings. 

Significant differences (p = 0.03) were detected 

among competitive matrices for percent antelope bitterbrush seedling survival at the end of the first 

summer. Percent antelope bitterbrush seedling survival averaged 19.7 in bluebunch wheatgrass, 11.9 in 

crested wheatgrass, 9.1 in control, and 6.6 in cheatgrass matrices. No significant difference between 

percent seedling survival in bluebunch and crested 

matrices was exhibited, although that trend is evident. Percent antelope bitterbrush seedling survival 

was significantly higher in bluebunch matrices than 

in the cheatgrass and control matrices. The analysis 

also showed a trend for higher seedling survival in 

crested matrices than in the cheatgrass and control 

matrices. One reason for lower survival in the 

cheatgrass and control matrices, versus the wheatgrass matrices, may be the tendency for bur buttercup 

densities to be higher in the control and cheatgrass 

matrices. Bur buttercup has been shown to be a strong 

competitor that negatively affects establishing plants 

(Buchanan and others 1978; Davis and Harper 1990). 

In addition, bitterbrush seedlings did not have any 

substantial thermal or protective cover in the relatively open control and cheatgrass matrices compared 

to the two wheatgrass matrices. 

Antelope bitterbrush seedling survival exhibited a 

steady decline over time (fig. 4). At the conclusion of 

the study, July 1994, an overall decline in percent 

antelope bitterbrush seedling survival from the previous year was noted. However, the order and relative 

Pssp Agcr Brte 

Competitive Matrix 

-1 April 29, 93 

[-I May 13, 93 

V7A May 20,93 

May 27,93 

hT\1 June 4,93 

June 25,93 

August 2,93 

1-1 July 12,1994 

Control 

Figure 4-Percent antelope bitterbrush seedling survival in the four different 

competitive matrices from germination in 1993 40 mid-summer 1994 (interaction, 

p = 0.01). 

USDA Forest Service Res. Pap. RMRS-RP-16. 1999 
magnitude was unchanged from the end of the previous year. Second year survival of antelope bitterbrush 

seedlings was significantly higher in the bluebunch 

wheatgrass matrices than any other (p = 0.08). 

Concl usions 

Results from this study support the hypothesis that 

introduced species such as crested wheatgrass and 

cheatgrass, as well as bur buttercup, lower the survival of antelope bitterbrush seedlings relative to the 

native bluebunch wheatgrass. This negative effect can 

be attributed, at least in part, to the ability of these 

introduced species, especially crested wheatgrass, to 

extract more soil moisture than bluebunch wheatgrass. Even in a year where the natural precipitation 

pattern exceeded the normals in both the number of 

events and magnitude, the fact that bitterbrush 

seedlings in bluebunch wheatgrass matrices had less 

negative xylem pressure potentials than seedlings in 

the other competitive matrices further supports the 

hypothesis that crested wheatgrass, cheatgrass, and 

bur buttercup exploit soil moisture to a greater extent 

than the native bluebunch wheatgrass. 

Bluebunch wheatgrass has co-evolved with various 

shrubs, including antelope bitterbrush. Thus, it is 

reasonable to assume that these species are able to 

coexist. When the temporal physiological activity balance within native communities is disrupted with the 

introduction of cheatgrass and crested wheatgrass, 

the seedlings of many native shrub species may be 

unable to successfully compete for the limited moisture and nutrients. If shrub recruitment is inhibited, 

existing shrub stands will eventually become decadent and slowly disappear. 

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USDA Forest Service Res. Pap. RMRS-RP-16. 1999 

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(Not all prohibited bases apply to all programs.) Persons with disabilities who

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print, audiotape, etc.) should contact USDA’s TARGET Center at 202-720-2600

(voice and TDD).

To file a complaint of discrimination, write USDA, Director, Office of Civil Rights,

Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington,

DC 20250-9410 or call 202-720-5964 (voice or TDD). USDA is an equal opportunity provider and employer.

ROCKY MOUNTAIN RESEARCH STATION

RMRS

The Rocky Mountain Research Station develops scientific information and technology to improve management, protection, and use of

the forests and rangelands. Research is designed to meet the needs

of National Forest managers, Federal and State agencies, public and

private organizations, academic institutions, industry, and individuals.

Studies accelerate solutions to problems involving ecosystems,

range, forests, water, recreation, fire, resource inventory, land reclamation, community sustainability, forest engineering technology,

multiple use economics, wildlife and fish habitat, and forest insects

and diseases. Studies are conducted cooperatively, and applications

may be found worldwide.

Research Locations

Flagstaff, Arizona Reno, Nevada

Fort Collins, Colorado* Albuquerque, New Mexico

Boise, Idaho Rapid City, South Dakota

Moscow, Idaho Logan, Utah

Bozeman, Montana Ogden, Utah

Missoula, Montana Provo, Utah

Lincoln, Nebraska Laramie, Wyoming

*Station Headquarters, 240 West Prospect Road, Fort Collins, CO 80526