Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 1/17/2004
Publication Date: 1/24/2004
Citation: Hendrickson, J.R., Walker, J.W., Kay, C.E. 2004. Long-term vegetation change in the centennial mountains. Society for Range Management Meeting Abstracts. Interpretive Summary:
Technical Abstract: There is considerable controversy over the past and current role of livestock grazing in changing the vegetative communities of the western United States. The use of repeat photographs can provide some insight into long-term changes within broad community types. An extensive search was made to locate historical photographs of the Centennial Mountains along the Idaho-Montana border. These photographs were taken to the field and modern photographs were taken to reproduce the historical scenes as close as possible. Over 100 photosets were complied throughout the area. These photosets represented a diverse group of communities including montane grasslands, sagebrush, coniferous forests, aspen, subalpine meadows and willow communities. While it is difficult to determine species shifts within communities, an evaluation of these photosets suggest that conifers have increased markedly while many of the other communities have decreased in extent. Several factors probably contributed to the shift, however, a change in the historic fire regime may be the leading cause of the increase in conifers. Long-term livestock grazing appeared to have little impact on the willow communities or soil erosion. These photosets suggest that grasslands, sagebrush, meadow and aspen communities will continue to have conifer encroachment unless the historic fire regime is reimplemented.