An Assessment of Cotton Tolerance To Pyroxasulfone, Acetochlor, and S Metolachlor

Residual herbicides applied preplant, PRE, or POST are necessary to maintain adequate weed control in cotton.  Commonly used postemergence residuals labeled for use in cotton include s-metolachlor and acetochlor.   A similar residual herbicide, pyroxasulfone is being developed for use in corn, wheat, and soybeans.  A series of studies were conducted to compare cotton tolerance to the current standards (s-metolachlor and acetochlor) and pyroxasulfone.  These studies determined that pyroxasulfone applied PRE or POST caused undesirable crop injury and yield loss.  Further details will be given concerning the comparison between s-metolachlor and acetochlor.