Photo by Josh McGinty.) Resistance issues He said producers need to be ready to go early in the season. Identifying key problem weeds is essential. He cited pigweed, common waterhemp and careless weed as resistance challenges. “Pigweed and waterhemp are prolific seed producers,” McGinty said. “One female plant can producer 200,000 or more seed and may exceed one million under favorable conditions.” He said these weeds have shown resistance to atrazine, glyphosate, and ALS herbicides in South Texas. He said pre-plant incorporated/preemergence herbicides are critical in managing these weeds. In cotton, he recommends a preplant/pre-plant incorporated application with yellow herbicides. He would add a preemergence application of Cotoran/Caparol plus a group 15 product. In sorghum, he recommends atrazine plus a group 15 herbicide. “We may have mesotrione as an option in the near future.”