Managing Aspen in Western Landscapes
September 21-23, 2004, Hunter Conference Center, Cedar City, Utah
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Wednesday, September 22, 2004 | Morning Session
Aspen Delineation ProjectDavid Burton, Principal Investigator, Aspen Delineation ProjectPacific Southwest Region, USDA Forest Service and California State Office: Bureau of Land Management, Penryn, California
(Description not available)
Robert B. Campbell, Jr., Ecologist, Fishlake National Forest, Richfield, Utah; Coauthors Dale L. Bartos, Linda M. Chappell, and Kevin P. Greenhalgh
The Tushar Mountains, Fishlake National Forest in south-central Utah, have more than 100,000 acres of mixed-conifer/aspen ecosystems. A variety of treatments occurred in this area including: the Grindstone Flat clearcut and exclosure study in 1934; the Betenson Mill wildfire in 1958; and the Betenson Flat spruce harvest in 1972. These treatments gave rise to vigorous young stands of quaking aspen.
All of these treatments were in the path of the Pole Creek wildfire that burned through the area in 1996 and scorched nearly 8,000 acres. The Pole Creek fire burned around these aspen stands that were about 20, 40, and 60 years old. All were effective firebreaks during the 1996 wildfire. This landscape example shows that young aspen stands can be effective firebreaks for at least 60 years.
Guidelines are provided for the types and strategic placement of treatments. Managers are encouraged to plan treatments in mixed-confer/aspen forests to compartmentalize the expanse of flammable landscapes. Such actions will reduce the risk of widespread unwanted wildland fires.
Phil Dittberner, Plant Ecologist, Bureau of Land Management, Denver, Colorado; Coauthors Mark Simmons and Mary Barkworth
A collaborative Project with Colorado State University Herbarium, Utah State University Herbarium, Canyons of the Ancients National Monument, Colorado Canyons National
Conservation Area, Gunnison Gorge National Conservation Area, and Grand Staircase-Escalante National Monument, the Plant Information Network II (PIN II) is a database that includes information about plant species found in Colorado and Utah. Particular emphasis and effort has been expended to include the information about species found in the following areas: 1) Canyons of the Ancients National Monument, 2) Colorado Canyons National Conservation Area, 3) Gunnison Gorge National Conservation Area, and 4) Grand Staircase-Escalante National Monument. The database includes a broad spectrum of information about those species including taxonomic, biologic, geographical, ecological, and economic. The database is in an Access database and can be easily queried to obtain many combinations of information about plant species. Some of this information is available from other places but not in queryable form that can be easily obtained in short time frames. Other databases often are in large table or narrative formats. Examples of some of the descriptors are as follows:
1. Taxonomic – family, genus, species, infraspecific, common name
2. Biologic – anthesis, CO2 fixation, habit, life cycle, reproduction,
3. Geographic – distribution by counties, elevation ranges, endemic, origin,
4. Ecological – trophic status, habitat, mycorrhizal relationships, nodule forming, nitrogen fixing, cover value, disturbance indicator, erosion control potential, establishment requirements, growth on soils, growth on slopes, soil depths, potential biomass production, vegetation associations,
5. Economic – hayfever causing, edible, energy value, food value for wildlife and livestock, short and long term revegetation potential, palatability, poisonous for livestock, protein value, weediness
Aspen Dynamics in the Warner Mountains of California(Page 2)Mary Flores, Wildlife Biologist, Warner Mountain Ranger District, Modoc National Forest, Cedarville, California; Coauthor Dr. James Laacke
Over the last century aspen has suffered a significant reduction in area in the Western United States. Comparison of vegetation data from 1930 and 1993 indicate that the Warner Mountains of Northeastern California are no exception with an 85% reduction in area covered. Often these changes may take place over a matter of decades. Changes overall and within individual stands are described, including vegetation replacing aspen within 1930's boundaries.
Bobette, E. Jones, Wildlife Biologist, Eagle Lake Ranger District, Lassen National Forest, Susanville, California; Coauthor Tom H. Rickman
An aspen inventory and risk assessment project is being conducted on the Eagle Lake Ranger District (ELRD), Lassen National Forest. This project was initiated due to observed declines in health and distribution of aspen stands on ELRD. Objectives of this project are to 1) produce a complete inventory of aspen on ELRD by 2004, and 2) provide stand-specific management recommendations and include these recommendations in NEPA documents that will allow the required restoration activities to take place. Each aspen stand is delineated using Global Positioning Systems (GPS), and assessed based on risk factors identified by Bartos and Campbell (1998). Management recommendations are based on observed stand conditions. To date, 557 stands totaling 1,278 hectares with a mean stand size of 2.1 hectares have been inventoried. Eighty-three percent of the stands have received a High or Highest priority rating, indicating that aspen are at risk. Aspen is considered a keystone species, and aspen communities are critical for maintaining biodiversity in western landscapes. Loss of aspen can be attributed primarily to successional processes that occur in the absence of natural fire regimes and with excessive browsing. Continuation of these processes that have existed for the past 100-140 years on the ELRD will result in the eventual loss of most aspen stands. ELRD’s extensive inventory and restoration efforts are an attempt to avoid this loss.
Valerie D. Hipkins, Forester, National Forest Genetics Laboratory, Placerville, California; Coauthor Jay Kitzmiller
Resource managers have become increasingly concerned over the apparent decline of Quaking Aspen in the western United States. Factors leading to these changes include fire suppression, livestock grazing, wild ungulate browsing, conifer succession, and perhaps climate change. To aid in the development of conservation and restoration strategies for aspen, we investigated genetic variability, clonal diversity, levels of differentiation, and patterns of geographic variation among 663 aspen individuals located in 82 stands from 8 watersheds throughout the western slope of the central Sierra Nevada, California. Genetic data show that, as a group, the aspens are genetically variable, as determined by starch gel electrophoresis. Individual stands, however, consist of only one to eleven genetic individuals and are much less variable. Forty of the 82 stands are monoclonal. Watersheds are not monoclonal but instead contain between three to 41 clones (average = 25.5). The geographic patterning of genetic variation detected by the allozyme data can be used to delineate genetic restoration units and to prioritize conservation efforts. Results from the study can be used to identify priority stands for in situ and ex situ protection, including those that contain large amounts of genetic variation, are highly differentiated, or contain rare alleles.
Eric J. Larsen, Assistant Professor of Geography/Geology, University of Wisconsin – Stevens Point, Stevens Point, Wisconsin; Coauthor William J. Ripple
Age-structure analysis of aspen was conducted on Rocky Mountain elk winter range in the northern Yellowstone area by collecting increment cores from aspen trees in Yellowstone National Park, the Gallatin National Forest, and the Sunlight/Crandall area of the Shoshone National Forest. Our goal was to compare aspen age structure for elk winter range in the park with age structures developed for elk winter range in the national forests. We collected increment cores from aspen in three diameter size classes and three aspen habitat types (xeric, mesic, and scree). A special effort was made to collect increment cores from the relatively rare scree habitat type, since scree forms a "natural exclosure" where browsing pressure on aspen is reduced. The age structure of aspen in Yellowstone was significantly different from the age structures of aspen in either of the national forest areas. The Gallatin and Sunlight/Crandall age structures were not significantly different. Only 6% of aspen stands in Yellowstone contained stems that originated from 1920–1989, while 87% and 84% of the stands in the Gallatin and Sunlight/Crandall areas, respectively, contained stems from that period. Within Yellowstone, the age structure of aspen in the scree habitat type differed significantly from the mesic and xeric sites that were available for browsing. Aspen stems originating after 1920 dominated the scree stands, while trees originating between 1870 and 1920 dominated the non-scree stands. Aspen stands have successfully recruited new stems into their overstories in all habitat types from 1880–1989 in elk winter range on national forest areas surrounding the park. Within the park, aspen stands recruited new overstory stems between 1860 and 1929 in all habitat types. Since 1930, Yellowstone aspen have recruited overstory stems mostly in scree habitat type stands and other areas of reduced browsing pressure.
John D. Shaw, Rocky Mountain Research Station, Forest Inventory and Analysis, Ogden
(Description not available)
Michael D. Smith, Soil Scientist, Fishlake National Forest, Richfield, Utah; Coauthors Wanda Bennett, Jenneka Jewkes, and Robert B. Campbell
Soils for the entire Fishlake National Forest were mapped at a scale of 1:24,000 to complete a 3rd order soil survey on 1.4 million acres of public lands. Nearly 400 soil map symbols were used to represent more than 17,000 soil polygons. Polygon sizes typically ranged from 25 to 200 acres on the uplands while others measured less than 10 acres in riparian zones and wetlands. Each soil map symbol was assigned an aspen regeneration code; then a forest-wide map was produced. The potential for aspen regeneration is displayed in one of four ratings. The potential aspen regeneration ratings are good, fair, poor, and unsuited. Rating descriptions include the following information. Good indicates that the soil properties and site characteristics are generally well suited for sustaining aspen communities. Fair is used to identify areas of aspen that are currently at risk to stand replacement by conifers. Poor means that the area is considered to be quite marginal for successful aspen regeneration following all types of ground disturbance. Unsuited is used to display the areas that will not support aspen forests. Management recommendations for each rating category are also included. This display has proven useful for assessments and project planning, implementation, and monitoring.
Tour 1: Fishlake National Forest, Beaver Ranger District Tour 2: Cedar Breaks
Additional Documents and Information
Aspen Packet: A list of additional aspen related reading