Progress 12/01/03 to 11/30/08
Outputs
OUTPUTS: Out puts of the project include experiments to document and understand the impacts of exotic invasive plant species on the Snake River Plain Idaho and on great Basin areas of Idaho, Utah and western Wyoming. The research is critical to understanding impacts of exotics on the sagebrush ecosystem and thus indirect impacts on potential listings of sagebrush obligate wildlife species (pygmy rabbit, greater sage grouse etc.). Initial examination of a native shrub plant species winterfat ( Kraschenninikovia lanata) recruitment associated with the invasion of the exotic annual grass Cheatgrass (Bromus tectorum). THis research revealed the presence of a secondary invasion of a more problematic exotic perennial species rush skeletonweed (Chondrilla juncea). As a result of this project, we have expanded our research to this secondary invasive species which appears to be more problematic because it is long-lived and rapidly reproduces from roots or seed following wildire. Outputs include the experiments, mentoring of 2 postdoctoral researchers, peer-reviewed publications, presentation at national and international meetings and a USFS General Tech Report, an online technical report available through the Forest Service websites. PARTICIPANTS: Ann L. Hild, lead investigator, University of Wyoming. Direction of post-doctoral assistants, and graduate students. Design and implementation of both winterfat and skeletonweed research. Authorship of publications and presentations. Nancy L. Shaw, Research Botanist, US Forest Service, Boise Idaho. lead investigator, University of Wyoming. Direction of post-doctoral assistants, and graduate students. Design and implementation ofboth winterfat and skeletonweed research. Authorship of publications and presentations. Direction of research activiities on Snake River Plain and research technicians. C,Lynn Kinter, post-doctoral research asosciate, implementation of post-fire skeletonweed research. B. A. Mealor, post-doctoral research assosciate, authorship of post-fire skeletonweed research. J. Muscha. graduate research assistant on greenhouse winterfat project in Wyoming. J. Gurr, D. Scholten and M Scholten. Undergraduate research technicians. TARGET AUDIENCES: Target audiences include residential and agricultural communities influenced by wildfire in the intermountain west and economic impacts of wildfire in the area. Audiences are management professionals including land managers, agency, local and private. All population groups and ethnic minorities are socially and economically influenced by the potential listing of sage grouse or other sagebrush obligate species. Efforts include presentations and publications to deliver science-based knowledge to managers via laboratory instruction of students and technicians experiential learning opportunities via the research effort and extension and outreach via poster, paper and web-based information dissemination. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The research has revealed two outcomes that have altered knowledge available on both a native shrub species and two exotic invasive species. First, local sources of the native shrub winterfat were compared to regionally available commercial seed to understand their success in competing with cheatgrass. We found the local Snake River Plain seed source less competitive, thus altering our knowledge of seed selection for revegetation on the Snake River Plain. Second, we documented for the first time, the seed recruitment and vegetative reproduction of the secondary perennial invader Rush skeletonweed inside and outside Wildfires and documented the potential of disturbance, fire and management practices for speeding the invasion of this species. As a result, we are increasing the knowledge of the impacts of prescribed fire and soil disturbance via agricultural treatments on this exotic invasion. Both outcomes have impact for our understanding of the influence of exotic species on former Sagebrush habitat. Because of the importance of the sagebrush ecosystem to obligate wildlife species, post-fire rehabilitation, and control of erosional forces on the Snake River Plain and the sagebrush ecosystem overall, the impact of this research will greatly influence quality of life for the agricultural community and the nation by enhancing our ability to return sagebrush communities to this important region. Improved revegetation efforts and limit of exotic invasions will move the systems nearer to supporting sagebrush obligate wildlife species once common there.
Publications
- Shaw, N.L., A.L. Hild, J.E. Gurr, D.L. Scholten, and M.D. Scholten. 2006. Population structure and recruitment of winterfat as influenced by the presence of cheatgrass. Proc: Shrublands Under Fire: Disturbance and Recovery in a Changing World. Fourteenth Wildland Shrub Symposium 6-8 June 2006. Cedar City, Utah. Poster.
- Shaw, N.L., A.L. Hild, and L. Kinter. 2008. Chondrilla juncea L.: Post-fire Invasiveness in the Shrub Steppe of Western North America. Proceedings: Joint Meeting, International Grassland Congress and International Rangeland Congress. 29 June - 5 July, 2008. Hohhot, China.
- Kinter, C.L., B.A. Mealor, N. L. Shaw and A.L Hild. 2007. Post-fire invasion potential of Rush Skeletonweed (Chondrilla juncea). Rangeland Ecology and Management 60 (4):386-394.
- Shaw, N. L. and A. L. Hild. 2007. Grassland, shrubland and desert ecosystems program, Boise, ID. Rush skeletonweed (Chondrilla juncea L.) on Idahos Snake River Plain. USDA Forest Service, Rocky Mountain Research Station. Technology Transfer Fact Sheet, http://www.fs.fed.us/rm/boise/research/shrub/projects/shaw_rust_tech_ transfer110107.pdf
- Hild, A.L., J.M. Muscha, and N.L. Shaw. 2008. Emergence and growth of four winterfat accessions in the presence of the exotic annual cheatgrass. pp. 147-152 In: Sosebee, R.E.; Wester, D.B.; Britton, C.M.; McArthur, E. Durant; S. Kitchens, comp. 2007. Shrubland Dynamics-Fire and Water: proceedings. 2004 August 10-12; Lubbock, TX. Proceedings RMRS-P-47. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. avail. online: http://www.fs.fed.us/rm/pubs/rmrs_p047.html.
- Shaw, N.L. and A.L. Hild. 2008. Chondrilla juncea demography following wildfire on the Snake River Plain. Joint meeting; American Forage and Grassland Council and the Society for Range Management Annual Meeting Jan 26-31, 2008. Lexington, KY. Poster.
|
Progress 01/01/05 to 12/31/05
Outputs
We examined the germination ecology of local winterfat populations to determine the effect of seedbed microenvironments on germination of naturally dispersed or planted seeds. In mid November 2000, seeds from 3 NCA locations were placed in mesh bags and planted on the soil surface or covered lightly with soil. Bags were recovered monthly through mid March 2001, and germination was compared among treatments and control seeds stored dry or given a 14 day prechill prior to incubation. Germination response was generally similar for the 3 locations. Over the 4-month period, germination of dry controls averaged 28% of live seeds. Five percent of dry seeds germinated following a 14-day prechill with an additional 56% germinating during incubation. Field germination of surface planted seeds was 4% in December and 100% by March. Covering seeds with soil accelerated the process with all live seeds germinating by February. Field planted seeds not germinating prior to recovery did
so rapidly in incubation. Late fall planting with light soil covering exposes seeds to cool, moist seedbeds that enhance germination, permitting rapid emergence when favorable combinations of moisture and temperature conditions are encountered in early spring.
Impacts
Because of the 1979 wildfires and cheatgrass invasions, the shrublands of the USDI-BLM Snake River Birds of Prey National Conservations Area have been reduced by more than 50%. Shrubs such as winterfat that dominated this area form shrub mosaics that provide essential habitat for small mammalian prey base of nesting raptor species. The recruitment of new shrub seedlings is critical to maintaining shrubland demography to support this trophic pyramid.
Publications
- Hild, A.L., Muscha, J. and Shaw, N.L. 2005. Emergence and growth of four winterfat accession in the presence of cheatgrass. In: Sosebee, R. E., comp. 2005. Shrubland dynamics: fire & water: proceedings; 2004 August 10-12; Lubbock, TX. Proc. RMRS-P-xx. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station.
- Shaw, N.L. and Hild, A.L. 2006. Germination of winterfat in response to seedbed environment in southern Idaho. In: Wildland Shrub Symposium Proceedings; 6-9 June, 2006. Shrublands Under Fire. St. George, UT.
|