Ecology and Management of Aspen Rangelands
The Society of Range Management Annual Meeting
February 11-16, 2007
Organized and hosted by
The Nevada Aspen Working Group and The Aspen Delineation Project
SECTION I: ASPEN ON RANGELANDS
1. ASPEN ECOLOGY AND BIODIVERSITY: AN OVERVIEW (20 minutes)
DAVID BURTON, Aspen Delineation Project, 2070 Orange Drive, Penryn, CA 95663, (916) 663-2574,
Abstract: While the significance of quaking aspen (Populus tremuloides) communities is well established—communities rich in biodiversity and a favored habitat and forage area for an assortment of wildlife species and livestock, this significance is becoming in twined in a web of rangeland management issues in western North America. Resource agencies are being asked to take a far more active role in the conservation of an ever-broadening range of wildlife species, some of which are considered to be at risk. At the same time, private landowner and land permittees are trying to maintain the quality and productivity of rangelands used for domestic ungulate production. However, thinking about conserving these species one species at a time, whether wild or domestic, is often impractical and unsustainable. Thus, there is an increasing awareness that management, preservation and restoration of habitat are critical for long-term sustainable management of domestic and wildlife populations. The foundation for managing aspen communities comes through an understanding of the ecology of aspen and its associated species. This foundation provides resource managers the tools for sustaining this unique habitat on the landscape.
DALE BARTOS, Rocky Mountain Research Station, Forestry Sciences Laboratory, 860 North 1200 East, Logan, UT 84321, (435)-755-3567, Email: email@example.com
Abstract: Aspen decline and die-off are two specific issues that are currently of concern in the western U.S. Normal aspen succession or decline has been addressed by land managers for many years. Changes in natural processes such as disrupted fire regimes, utilization of fine fuels by ungulates, and excessive browsing of aspen regeneration has all added to this decline. The more recently reported aspen die-off occurs when mature trees die quickly within a year or two and no new sprouting occurs, indicating that the lateral roots may also be dead. If that is the case, then aspen will not re-occupy the site. There is no physiographic characteristic that is unique to these die-off events. This phenomenon has been reported from Arizona to Alberta. Die-off can affect one clone and leave adjacent clones untouched; only mature overstory trees are impacted. Cytospora cankers, poplar borers, and other damage or stress agents are often associated with die-off epicenters; however the possibility of a yet-unknown invasive disease or insect cause still exists. Is there a relationship between this rapid die-off and animal impacts that occur in the form of browsing or barking of trees? Aspen die-off has been reported for several years in Utah and Arizona, but only recently has become apparent in Colorado, where recent aerial surveys indicate 20,000+ acres are affected. The apparent death of roots is disturbing, as aspen cannot sprout back if the root system is dead. We are unable to predict how long the die-off will persist, or how much area will be affected. In some areas of the west, mature stable aspen stands are experiencing die-off that occurs over a 10-12 year period. In 80-90% of the cases, sufficient aspen regeneration has occurred to reestablish the stands. Approximately 10% of the time excessive utilization of the regeneration by ungulates causes total die-off.
3. RESTORING THE REST: ASPEN IN A LANDSCAPE CONTEXT
TOM RICKMAN, United State Forest Service, Lassen National Forest, 447-050 Eagle Lake Road, Susanville, CA 96130, USA, 530/252-5864, Email: firstname.lastname@example.org.
Bobette E. Jones United State Forest Service, Lassen National Forest
Abstract: Aspen restoration has been widely identified as a priority in western states due to disruption of natural disturbance regimes and a long history of land uses that have negatively affected aspen communities. Disruption of fire regimes has resulted in advancing succession of conifers that has shaded out mature aspen trees, decreased success of aspen suckering, and in some cases has resulted in the complete replacement of aspen by conifers. In addition, excessive herbivory from wild ungulates and domestic livestock has decreased the ability of aspen to successfully regenerate for over 100 years. These influences, as well as other land uses such as timber harvest, have resulted in landscape level changes to vegetative communities that extend beyond the small proportion of landscapes that contain aspen communities. Although aspen restoration treatments are extremely important in managing for biodiversity across landscapes, emphasizing restoration treatments in these communities may ignore larger restoration opportunities. We compare data from a large-scale aspen inventory to other data (including General Land Office surveyor notes, historical documents and photographs) to indicate that an aspen-only restoration program may represent only a 1% approach to landscape restoration.
4. PANEL DISCUSSION: BURTON, BARTOS, AND RICKMAN (20 MINUTES)
SECTION II: STUDYING FACTORS AFFECTING
5. Water Resource Impacts due to Conifer Removal to Restore riparian Aspen stands (20 minutes)
Kenneth W. Tate, University of California, Plant Sciences, Mail Stop 1, One Shields Ave., Davis, CA 95616-8780, USA, 530/754-8988, Fax: 530/752-4361, Email: email@example.com.
Bobette E Jones, United State Forest Service, Lassen National Forest
Trembling aspen (Populus tremuloides michx.) occurs in the montane zone of California’s Sierra Nevada/Cascade range. Aspen is considered a keystone species providing critical habitat to support plant and animal biodiversity in the region. Declines in the health and distribution of aspen stands across the region have been observed over the past century. This presentation reports impacts to water resources and riparian areas observed following conifer removal to restore degraded riparian aspen stands on the Lassen National Forest (LNF) in northeastern California. Concerns about negative secondary effects of near-stream conifer removal impede restoration of aspen stands in riparian areas. We have incorporated rigorous monitoring into several recent restoration projects to provide data to address these concerns, adapt restoration techniques if warranted, and obtain restoration objectives. We will report and discuss impacts to water quality (dissolved oxygen, temperature, nutrients, etc.), hydrology (soil moisture, streamflow), soil quality (bulk density, nutrients, OM, etc.), and in-stream habitat (canopy, macroinvertebrate community dynamics, etc.) observed following mechanical removal of conifers from riparian aspen stands on LNF.
6. ASPEN RESTORATION IN THE NORTHERN GREAT BASIN. (20 minutes)
JON BATES, Rangeland Scientist, USDA Agricultural Research Service,
67826-A Hwy 205, Burns, OR, 97720, (541) 573-8932
Rick Miller, Rangeland Ecology, Oregon State University
Kirk Davies, USDA - Agricultural Research Service, Burns OR
Abstract: Western juniper woodlands are rapidly replacing lower elevation (< 2100 m) quaking aspen stands throughout the northern Great Basin. Aspen restoration is important because these communities provide important seasonal and year-long habitat for wildlife species and contain a high diversity of understory shrubs and herbaceous species. We have studied several juniper removal treatments to restore aspen woodlands. Treatments have included, selective cutting to increase surface fuels followed by fall or early spring burning, and prescribed fire alone. Selective cutting has involved cutting 30 to 75% of mature juniper trees. We tested the effectiveness of treatments at removing juniper from seedlings to mature trees, measured aspen sucker recruitment, and evaluated the recovery of shrub and herbaceous cover and diversity. Prescribed fires applied in the fall are the most successful at eliminating all remaining juniper trees and seedlings and stimulating aspen suckering. However, fall fires result in severe reductions in herbaceous cover and may increase weed species. Spring burning produces less severe fires, which are not as effective at removing remaining mature juniper trees or seedlings. In the spring treatments there are enough junipers remaining to re-dominate aspen stands within 80 years. Aspen suckering was 40% lower in the spring burning compared to fall burning. Spring burning has little impact to the understory which recovers rapidly and is dominated by perennials. If management objectives are to eliminate invasive western juniper with minimal cutting and stimulate greater aspen suckering, fall burning appears to be the most successful. If the objective is to rapidly increase perennial herbaceous cover and moderately increase aspen suckering, spring burning is recommended. With spring burning follow-up management will be necessary to remove juniper that are missed in initial treatments.
7. BROWSE EFFECTS AND THE INFLUENCE OF FORAGE AVAILABILITY AND QUALITY ON LIVESTOCK FORAGE SELECTION IN ASPEN COMMUNITIES. (20 Minutes)
Bobette E. Jones, United State Forest Service, 447-050 Eagle Lake Road, Susanville, CA 96130, USA, 530/252-5816, Email: firstname.lastname@example.org
Kenneth W. Tate, Plant Sciences, University of California, Davis, CA 95616
David F. Lile, University of California Cooperative Extension, Susanville, CA 96130
Shannon R. Cler, Plant Sciences, University of California, Davis, CA 95616
Concern exists regarding the decline of aspen and the lack of successful regeneration in aspen stands throughout the west. Excessive herbivory by wild ungulates and domestic livestock has contributed to the decline of aspen communities in western states by reducing or preventing successful vegetative regeneration. Conflicts may therefore arise between livestock grazing and aspen restoration. A challenge for land managers is to balance conservation and restoration of aspen communities with livestock use. Fencing is the most effective and common management practice to restore degraded aspen stands; however fencing may not be practical on a landscape scale. Improving aspen stand vigor by increasing successful regeneration while sustaining livestock grazing depends on an understanding of, 1) how aspen regeneration responds to timing, intensity, and frequency of livestock browsing, and 2) livestock grazing behavior within meadow and aspen plant communities. Two studies were conducted to address these questions. First we quantified annual growth of aspen regeneration that received a simulated browsing treatment, and predict how timing, intensity, and frequency of browsing affected annual growth. Second, we monitored forage quality and quantity and livestock utilization in meadows and aspen stands throughout the grazing season. We present results and implications for range management on public lands where aspen conservation and restoration are a high priority.
8. PANEL DISCUSSION: TATE, BATES, AND JONES (20 MINUTES)
SECTION III: MANAGEMENT CASE STUDIES
9. MONITORING ASPEN: A KEY TO INFORMED DECISION MAKING IN RANGELAND MANAGEMENT. (20 minutes)
DAVID BURTON, Aspen Delineation Project, 2070 Orange Drive, Penryn, CA 95663, (916) 663-2574, E-mail: email@example.com
Monitoring is a key component of aspen management. It gives managers an opportunity to make more informed decisions and to change practices as needed. On aspen rangelands, monitoring efforts can be used to detect responses to specific management activities, such as stocking intensity, duration, class of animal, and season of use.
This presentation presents an overview of aspen stand assessment and monitoring methodologies that have enabled resource managers to effectively develop, implement, and evaluate aspen management activities. The consistent threads through all of the protocols reviewed are attention to measuring the ecological condition of aspen communities, capture of factors changing that ecological condition, and assessment of the degree of change. These three focuses will be helpful to managers as they design and adjust management activities to benefit aspen.
10. ASPEN MANAGEMENT AND MONITORING ACROSS LANDOWNERSHIP BOUNDARIES IN THE PIONEER MOUNTAINS OF CENTRAL IDAHO (20 Minutes)
TESS O'SULLIVAN, Manager of Conservation Science Programs, Lava Lake Land & Livestock, P.O. Box 2249, Hailey, Idaho 83333, (208) 788-1378,
Michael S. Stevens, Lava Lake Land & Livestock, L.L.C., Hailey Idaho
Alan R. Sands, The Nature Conservancy, Idaho
ABSTRACT: Lava Lake Land and Livestock was organized in 1999 to (1) achieve landscape-scale conservation in the Pioneer and Boulder Mountains and in the Craters of the Moon area and (2) establish an ecologically-sound and financially-viable business that supports our conservation activities. The Company’s business is currently focused on all-natural and organic lamb production. Our grazing and conservation activities take place on 24,000 acres of private lands and 730,000 acres of lands administered by the Bureau of Land Management (BLM), the U.S. Forest Service (USFS), and the Idaho Department of Lands (IDL). One of our priorities is sustaining high quality aspen habitat. Studies conducted by the Conservation Data Center in 2001 when Lava Lake had assumed operational control of its public and private land assessed 99% of the aspen habitat as either fair or poor, with less than 1% in good to excellent condition. Since that time we have prepared a conservation plan, established an aspen habitat monitoring program, developed a multi-year grazing plan, made adjustments in livestock type and numbers, and have created stewardship based incentives for our sheep herders. We initiated aspen monitoring in 2003 and re-read transects in 2006 using quantitative monitoring protocols which evaluate regeneration and utilization. These protocols were based on Forest Service methodology. We are currently in the process of analyzing the results of our monitoring surveys, but anecdotal accounts throughout the Lava Lake operating area indicate signs of aspen recovery. Our partners include the BLM, National Park Service, USFS, U.S. Fish and Wildlife Service, IDL, Idaho Fish and Game, Blaine County, and The Nature Conservancy.
11. THE TROUT CREEK MOUNTAIN WORKING GROUP: A FIFTEEN-YEAR PERSPECTIVE. (20 minutes)
MARY HANSON, Oregon Department of Fish and Wildlife, 3406 Cherry Ave. NE, Salem, OR 97303-4924, 503-947-6253.
Abstract: The Trout Creek Mountain area in southeastern Oregon has a 130 history of livestock grazing from June to October. By the 1980s, that century of grazing had taken its toll on stream channels, riparian vegetation, and overall trout habitat. Stream banks were eroded, riparian vegetation was sparse, the water table had dropped, upland vegetation was encroaching into riparian zones, and aspen communities were nearly lost from the ecosystem. It was at this point that the endemic cutthroat trout had been recognized as unique and in need of protection. The severely degraded trout habitat placed the ranchers permits to graze cattle in the mountains in jeopardy.
In 1988, the Trout Creek Mountain Working Group (TCMWG) was formed to find a long-term solution that would provide for both the ecological health of the land (restoring stream conditions and trout habitat) and the cultural and economic well being of the ranching community. To achieve both, new grazing management strategies were needed. Without eliminating all grazing, the traditional way cattle used the mountain had be changed so that the riparian vegetation needed to preserve trout habitat could be restored. This case history explores the cooperative effort of landowners, governmental resource managers, and conservationists to accomplish these objectives. The case study examines the formation of the working group, the development of allotment management plans, the implementation of the management effort, and the results of the undertaking.
12. PANEL DISCUSSION: BURTON, SULLIVAN, AND HANSON (20 MINUTES)