Flazasulfuron is a selective herbicide registered for use in warm-season turfgrass. Concerns have been raised over its mobility surface water runoff. Studies were conducted Blacksburg, VA and Charlottesville, to evaluate injury Lolium perenne L. (perennial ryegrass) downslope of plots treated with transition-assisting herbicides, including flazasulfuron, pronamide, trifloxysulfuron sodium. (52 ...