Do perennial bunchgrasses exclude cheatgrass in post-fire rehabilitation?

View report.

Data on plant cover and density was collected on 67 sites in a 209,000 ha study area that varied in fire and post-fire rehabilitation history along gradients in elevation, soil texture, and precipitation. Multiple linear regression indicated significant inverse relationships between B. tectorum and both P. secunda and A. cristatum, but P. secunda had suppressed B. tectorum cover and density better than A. cristatum. A nonparametric multiple regression analyzing the effect of 86 abiotic and biotic independent variables indicated that elevation, mid to late season native perennial bunchgrasses, and the number of post-fire rehabilitation treatments (for B. tectorum cover) or time since most recent rehabilitation (for B. tectorum density) explained the most variation in Bromus tectorum suppression across the landscape.