Herbicides can persist and affect future crops. Many factors effect herbicide carry over; amount of moisture, soil PH, previous crop planted, soil texture, soil organic matter level, no-till, tillage, etc. When planning on rotating to another crop always check the product label first to look for rotation restrictions. This is a quick reference guide to common herbicides and their rotation restrictions for selected crops. Refer to label to see if field bioassays should be performed before planting rotation crops, especially for rotation intervals longer than 18 months.
Herbicide Rotation Restrictions
Marestail (also known as horseweed) is considered either a winter annual or biennial species that is often difficult to identify at the rosette stage. In the Dakota’s, marestail will germinate in the fall and bolt in the spring.