Mark VanGessel, Extension Weed Specialist; mjv@udel.edu
Many corn fields need postemergence treatment for weeds, but it maybe a week or two before the corn starts to shade the row middles. In this case, select an herbicide that will provide some residual weed control. Liberty, glyphosate, dicamba, or Aim/Cadet will not provide residual control. Consider atrazine if the corn is less than 12 inches, or a product with mesotrione (Callisto), Capreno, or Impact/Armezon for broadleaves. If you expect grasses to be a problem, then products such as Halex GT, Armezon PRO, or Capreno will help with residual control. Other products are labeled for corn less than 12 inches tall; refer to the Mid-Atlantic Field Crop Weed Management Guide for a complete list.