Author
Bates, Jonathan - Jon | |
SHARP, ROBERT - Bureau Of Land Management | |
Davies, Kirk |
Submitted to: International Journal of Wildland Fire
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/18/2013 Publication Date: 9/10/2013 Citation: Bates, J.D., Sharp, R.N., Davies, K.W. 2013. Sagebrush steppe recovery after fire varies by development phase of Juniperus occidentalis woodland. International Journal of Wildland Fire. 23:117-130. Interpretive Summary: Pinus-Juniperus L. (Piñon-juniper) woodlands have expanded into Artemisia tridentata Beetle (big sagebrush) steppe of the western United States primarily as a result of reduced fire disturbances. Prescribed fire has been increasingly employed to restore sagebrush steppe plant communities and to control expanding piñon-juniper woodlands. We compared vegetation recovery following cutting-prescribed fire treatments on Phase II (mid expansion) and Phase III (late expansion) western juniper woodlands located on Steens Mountain, Oregon. The herbaceous layer on Phase II woodland sites was comprised of native perennial and annual vegetation before and after fire while on Phase III sites the herbaceous layer shifted from native species to dominance by non-native weeds. The results suggest that woodland phase influences post-fire vegetation recovery and that Phase II woodland sites have a greater likelihood of recovery to native vegetation than Phase III woodlands. Technical Abstract: Pinus-Juniperus L. (Piñon- juniper) woodlands have expanded into Artemisia tridentata Beetle (big sagebrush) steppe of the western United States primarily as a result of reduced fire disturbances. Woodland control measures, including prescribed fire, have been increasingly employed to restore sagebrush steppe plant communities. We compared vegetation recovery following cutting-prescribed fire treatments on Phase II (mid expansion) and Phase III (late expansion) Juniperus occidentalis Hook. (western juniper) woodlands located on Steens Mountain, Oregon. The herbaceous layer on Phase II woodland sites was comprised of native perennial and annual vegetation before and after fire. On Phase III sites the herbaceous layer shifted from native species to dominance by non-native plants after fire. Artemisia tridentata. spp. vaseyana (Rydb.) Beetle (mountain big sagebrush) was the most abundant shrub in both woodland phases prior to fire. After fire, shrubs on Phase II sites were comprised of sprouting species and Ceanothus velutinus Dougl. (snowbrush). On Phase III woodland sites the shrub layer was dominated by C. velutinous. The results suggest that woodland phase influences post-fire vegetation recovery and that Phase II woodland sites have a greater likelihood of recovery to native vegetation. Results also indicate that sites transitioning from Phase II to Phase III woodland cross a recovery threshold where there is a greater potential for invasive weeds to dominate rather than native vegetation after fire. |