Efficacy and Safety of Combinations of Preemergence and Postemergence Herbicides in Cantaloupes

Sandea at 0.03 lb AI/A combined with rimsulfuron at 0.02 lb AI/A gave exceptionally good control of prostrate pigweed and lambsquarters at 98% and 96%, respectively, when applied postemergence (POST) in cantaloupes. Sandea applied POST in a tank-mix with increasing rates of rimsulfuron showed marginally acceptable to unacceptable crop injury. All POST applications of Sandea following preemergence (PREE) herbicides or applied alone provided 90% or better control of lambsquarters. Sandea and Strategy gave unacceptable control of pigweed and lambsquarters at 60-70% relative to the standard, Prefar. Sandea applied alone POST was less effective against pigweed than lambsquarters. A treatment of a PREE herbicide followed by Sandea was not as efficacious as the Sandea plus rimsulfuron tank-mix applied POST to control both pigweed and lambsquarters