Effects of fire and restoration seeding on establishment of squarrose knapweed (Centaurea virgata var. squarrosa)

Abstract

Squarrose knapweed (Centaurea virgata var. squarrosa), herein referred to simply as knapweed, is a noxious weed that invades both disturbed and healthy sagebrush communities. Fire, grazing, mining, recreation, and farming have all played a large part in the establishment of knapweed in Tintic Valley, Utah. This study was designed to look at the effect of fire on the establishment of knapweed in four community types, namely cheatgrass, crested wheatgrass, degraded sagebrush, and healthy sagebrush. Plots were either burned or left unburned after which subplots were seeded with knapweed. Results show that fire plays an important role in knapweed invasion especially in sagebrush communities. Knapweed establishment on cheatgrass plots did not vary between burn treatments, and knapweed establishment was lowest on crested wheatgrass sites.

Parent Publication

• Proceedings-Shrublands under fire: disturbance and recovery in a changing world; 2006 June 6-8; Cedar City, UT

Citation

Whittaker, Alison; Jensen, Scott L. 2008. Effects of fire and restoration seeding on establishment of squarrose knapweed (Centaurea virgata var. squarrosa). In: Kitchen, Stanley G.; Pendleton, Rosemary L.; Monaco, Thomas A.; Vernon, Jason, comps. 2008. Proceedings-Shrublands under fire: disturbance and recovery in a changing world; 2006 June 6-8; Cedar City, UT. Proc. RMRS-P-52. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 77-79