Another Tool in the Weed Management Toolbox

Fall-applied residual herbicides can be a valuable tool for weed management. It allows for weeds to be managed earlier in the season, before they become too large to control. Soil residual herbicides are a tool for managing herbicide resistant weeds because they utilize unique modes of action (Groups 3, 14, 15), and this is especially valuable in crops with limited in-crop options. Fall application can be preferable to spring as there is more opportunity for the herbicides to activate before early germinating weeds can show up.

Granular products are consistently effective, but liquid products can be applied with ground sprayers which may be more convenient and can also be mixed with glyphosate for perennial and winter annual weed control. However, soil residual herbicides come with important considerations such as moisture and rainfall requirements for activation. The rates and efficacy of these residual products are going to be influenced by the residue, soil texture, OM, and pH.