Native forb response to sulfometuron methyl on medusahead-invaded rangeland in Eastern Oregon

摘要: Medusahead (Taeniatherum caput-medusae (L.) Nevski), a non-native, winter-annual grass (Poaceae), has invaded rangelands throughout the western USA. is an aggressive competitor that crowds out native plants andreducesforageforwildlifeandlivestock.Sulfometuronmethylisasulfonylurea herbicideusedtocontrolmedusahead, but its effect on non-target forbs largely unknown. We assessed impact of autumn application sulfometuron methyl sagebrush/bunchgrass steppe eastern Oregon over 3 years. applied 70ga.i./ha (1.0oz. a.i./acre) to randomly selected locations three sites in split-plot-in-time (repeated-measures) experimental design. Three years after treatment, 6 11 forb species studied had significant reduction density (P <0.05), with densities ranging from 60% pre-treatment levels. The results this study suggest benefit medusahead control by should be weighed against damage species.