Integrating Herbicides and Re-seeding to Restore Rangeland Infested by an Invasive Forb-Annual Grass Complex

摘要

Millions of hectares of range and wild lands in the western U.S. have been invaded by non-indigenous forbs, including spotted knapweed (Centaurea stoebe), resulting in negative impacts like decreases in native plant abundance (May and Baldwin 2011) and forage production (Watson and Renney 1974). Because of these negative impacts, invasive forbs are often listed as noxious weeds and routinely controlled through integrated management methods like herbicide applications and release of biological control agents. While these tools can be quite effective, they often do not result in a plant community that meets management objectives because remnant desired vegetation is too scarce to fill voids previously occupied by weeds. Subsequently, the weedy forb may be replaced by an equally invasive secondary invader like the annual grass cheatgrass (Bromus tectorum) (Story et al. 2006, Stephen et al. 2009).