1a.Objectives (from AD-416):
1) Determine what factors (management, site/environmental characteristic, etc) promote native plant recruitment in crested wheatgrass plant communities.
2) Determine if crested wheatgrass displaces native vegetation from plant communities.
1b.Approach (from AD-416):
To accomplish the first objective, we propose to sample 100 crested wheatgrass plant communities across the northern Great Basin to determine what factors promote native plant recruitment in crested wheatgrass plant communities. Private and public land managers will be contacted to locate near-monoculture of crested wheatgrass and crested wheatgrass with native vegetation recruitment. Site, environmental, and management characteristics will be collected to determine their relationships with native plant recruitment into crested wheatgrass communities.
To determine if crested wheatgrass displaces native vegetation we will measure the densities and cover of perennial bunchgrasses in plots established in 1989 with specific densities of crested wheatgrass and seven native perennial bunchgrasses. Eight plots will be used to determine if crested wheatgrass density has increased and native perennial bunchgrass densities have decreased since the plots were established.
Progress was made on Objective 3 from parent Project 5360-11630-006-00D: Understand mechanisms of weed invasion and develop management strategies that can be used to restore rangelands that have been degraded by weeds or other disturbances. We sampled vegetation, site, and management characteristics at 50 crested wheatgrass stands to determine the effects of site and management factors on the recruitment of native vegetation into crested wheatgrass stands. We also identified over 50 more crested wheatgrass stands to sample in the future. Information gleamed from this study will help land managers restore and manage sagebrush steppe plant communities converted to crested wheatgrass stands.