ABSTRACT

Cotton injury has been a concern in Arkansas with the herbicide Envoke™ (trifloxysulfuron or CGA-362622). An experiment was conducted in 2003 at Marianna, AR, to evaluate cotton response to trifloxysulfuron, including visual injury, cotton growth and development using COTMAN, and yield. Trifloxysulfuron caused up to 30% cotton injury, primarily in the form of stunting, after 8-leaf postemergence applications. Internode growth was impacted, but growth and fruiting patterns were not. Trifloxysulfuron caused a 2- to 4-day delay in maturity, but seed-cotton yields were not affected. COTMAN is a valuable tool for measuring the effects of herbicides on cotton fruiting patterns and for comparing effects among herbicide treatments. However, it cannot substitute for visual injury assessments, which are of realistic concern to producers.