A 4 year study examined four treatments (spring herbicide only, repeated sheep grazing only, spring herbicide and repeated sheep grazing though out the summer, no herbicide or grazing) to control spotted knapweed (Centaurea maculosa) populations at two sites in Western Montana. The first site was along Bitterroot River near Missoula, MT (46.83° N, 114.05° W) and the second site was on the flood plain of the Clark Fork River near Drummond, MT (46.79° N, 113.20° W). Utilization levels were set at 95% for knapweed and 60% for grass. Density, biomass and percent cover for spotted knapweed and grass were measured before, during and after the study was completed.
Citations and enhanced abstracts for journals articles and documents focused on rangeland ecology and management. RSIS is a collaboration between Montana State University, University of Idaho, and University of Wyoming.