Farmers know that rotating crops is an effective strategy for controlling weeds.
Rotating herbicides also helps fight weeds, says agronomist Denise McWilliams of the University of Minnesota Extension Service. Rotating herbicides is particularly beneficial in hindering the development of herbicide-resistant weeds, she adds. McWilliams cites research from a four-year study of crop rotations and herbicides by Ohio and Virginia researchers. The study looked at population trends for weeds such as common lambsquarters, ragweed, several amaranthus species and jimsonweed at two sites. Cropping systems included continuous corn, continuous soybeans and corn-soybean rotations.