Performance of Sharpen in Oklahoma

Sharpen (saflufenacil) is a PPO (protoporphyrinogen) inhibitor recently introduced by BASF which has the potential to provide effective burn-down (post-emergence) activity on many troublesome weeds including horseweed. The lack of pre-season tillage (in no-till) and ineffectiveness of glyphosate has led producers to primarily depend on hormone-type herbicides (2,4-D or dicamba) for effective pre-plant control of horseweed. Currently there are very few effective chemical options for controlling horseweed pre-plant in cotton. In addition even the most effective hormone-based programs begin to lose effectiveness as weed size at application increases. Sharpen has proven effective in Oklahoma when attempting to control horseweed with preplant herbicide applications. In addition to the weed control benefits Sharpen may be useful as a defoliant or desiccant when trying to condition cotton prior to harvest. Applications to irrigated cotton were made this past year to evaluate the harvest aid performance of Sharpen in comparison to treatments considered to be standards for Oklahoma.