Preplant Control of Common Groundsel in Oklahoma

As more producers adopt no-till cotton production practices in Oklahoma the vulnerabilities of glyphosate based weed control programs continue to become exposed.  The number of producers experiencing difficulty controlling certain weed species in these systems continues to rise.  Common groundsel is one of these weed species.  Similar to horseweed this weed can germinate in the fall, early winter or spring.  However, in contrast to horseweed in Oklahoma, its growth habit can be much more aggressive earlier in the season.  Over the last few years many producers have experienced difficulty or in many instances complete failure when trying to control this weed with with postemergence applications of glyphosate.  This project focuses on the evaluation of traditional horseweed treatment programs and how effective those programs can be for the control of common groundsel.  Much like horseweed programs the use of hormone type herbicides (2,4-D and Dicamba) are the basis for these treatment programs but we also wanted to evaluate some additional options including paraquat and Sharpen.  Two locations were established one which included various combinations with glyphosate and another without the glyphosate component.