ARS | Publication request: The importance of maintaining perennial bunchgrass in the sagebrush steppe

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 25, 2012
Publication Date: February 25, 2013
Citation: Svejcar, A.J., Davies, K.W., Boyd, C.S. 2013. The importance of maintaining perennial bunchgrass in the sagebrush steppe [abstract]. 66th Annual Meeting of the Society for Range Management, February 3-7, 2013, Oklahoma City, Oklahoma. Paper No. 46.

Technical Abstract: The sagebrush steppe is generally described as an ecosystem at great risk from encroachment of invasive annual grasses and conifer woodlands, land use changes, climate shifts and fragmentation in general. A great deal of attention has been focused on sage-grouse and need for sagebrush cover and forbs as critical habitat elements. Probably the most pressing concern in the western sagebrush steppe is the conversion to invasive annual grasses and the dramatic shortening of the fire return interval. Cheatgrass (Bromus tectorum L.) in particular does very well with increases in atmospheric CO2 and winter temperatures. There is ample literature demonstrating the importance of large perennial bunchgrasses (PBGs) in halting the spread of annual grasses, especially at lower elevations. However, there is limited information on recruitment, mortality and life spans of PBGs. The existing literature suggests that average and maximum life spans are <10 yr. and around 30 yr. respectively. Recruitment is thought to be episodic, but the life span data suggests that recruitment will be required about once a decade to maintain PBG populations and reduce the threat of annual grass encroachment. Because of the difficulty in restoring annual grass dominated systems, maintenance of relatively intact plant communities should be a primary management focus for low to mid elevation sagebrush plant communities. If we are to reduce the number of acres lost to invasive annual grasses, a focus on PBG recruitment and mortality will be critical.