Declines in Gunnison sage grouse populations are thought to be related to habitat loss, fragmentation, and human induced habitat changes. In an attempt to improve the quality of early brood rearing habitat the Bureau of Land Management, Gunnison Field Office in Gunnison Colorado implemented a series of mechanical treatments designed to reduce sagebrush canopy cover and increase cover of graminoids and forbs. Brush mowing and Dixie harrow were utilized in 2005 to treat 30 percent of six 14 ac sites. In 2006 and 2007 shrub canopy cover, graminoid cover, forb cover, heights, and species richness were assessed to determine the vegetative response to each treatment. Sagebrush canopy cover was reduced to approximately 15 percent by both treatments. Mowing appeared to have no effect on forb or non-sagebrush shrub canopy cover, however, graminoid cover increased slightly post-treatment. Sites treated with the Dixie harrow had increased non-sagebrush shrub canopy cover, graminoid cover, and forb cover in post treatment years as compared to pretreatment. Heights for graminoids and forbs did not differ pre and post treatment ( p > 0.05) nor did species richness (p > 0.05) for either treatment.
Payton, Adam C.; Hayes, Sandra J.; Borthwick, Sandra M.; and Japuntich, Russell D.
"Short-Term Response of Shrubs, Graminoids, and Forbs to Mechanical Treatment in a Sagebrush Ecosystem in Colorado,"
Natural Resources and Environmental Issues:
Vol. 16, Article 24.
Available at: http://digitalcommons.usu.edu/nrei/vol16/iss1/24