Some researches state that willows (Salix spp.) on Yellowstone National Park's northern range have declined because of climatic change, fire suppression, reduced chemical defenses, or other natural factors. However, these claims are not supported by available data. Instead, the evidence suggests that willows have declined due to repeated browsing by an unnaturally large elk (Cervus elaphus) population. Prior to park establishment, predation by Native Americans kept ungulates from impacting Yellowstone's plant communities. By established standards, Yellowstone contains some of the worst overgrazed willow communities in the entire West. YNP willow condition is also a critical test of Yellowstone's "natural regulation" program. Elk browsing has also had a serious impact on aspen, cottonwood, and other plants in the park. In addition, Kay finds Singer et al.'s (1994) call for more research disingenuous. A committee of riparian experts developed a riparian research plan for the northern range at the request of Park Service, but their recommendations were not followed. On the other hand, if the decline in Yellowstone's willow communities is considered to be "natural" (caused by climatic change or the other factors), Singer et al. (1994) and the Park Service imply that ranchers throughout the West should be afforded the same consideration.
Citations and enhanced abstracts for journals articles and documents focused on rangeland ecology and management. RSIS is a collaboration between Montana State University, University of Idaho, and University of Wyoming.