Metolachlor herbicides are typically used as a preemergence, residual herbicide in corn (Zea mays L.), cotton (Gossypium hirsutum L.), soybean [Glycine max (L.) Merr], and a variety of other crops for the control of grasses and small-seeded broadleaves such as pigweeds (Amaranthus spp.). However, due to chemical principles of the metolachlor active ingredient and recent herbicide resistance evolution in Palmer amaranth (Amaranthus palmeri S. Wats.), losses in weed control have been observed in Arkansas.
Check out our latest publication which provides information regarding the metolachlor chemistry, how to effectively use the herbicide, and recent discoveries of herbicide resistance in the state of Arkansas: http://bit.ly/UAEXMetolachlor.