Weed control is best achieved with a combination of cultural, mechanical and chemical methods. Rotate crops and herbicides to limit the buildup of difficult weeds such as atrazine-resistant redroot pigweed, lamb’s-quarters and groundsel.

Light cultivation with a rotary hoe or tineweeder, prior to crop emergence and through to the 3 – 4 leaf stage, can effectively kill emerging weeds and improve activity of some pre-emergence herbicides. When the crop is well established, use a rolling cultivator to throw soil into the row to smother escaped weeds.

Effective chemical weed control begins with knowledge of the major weed species in the field. Often a combination of preplant, pre-emergence and post-emergence treatments is necessary. See Table 1, Corn Weed Control.