Don't plant into a weed problem unless you have a solution for killing the weeds. Spray as soon after harvest as possible with appropriate herbicides for the row crops to be planted the following spring. Then select the herbicides for the row crops to be planted the following spring. Then select the herbicides that can be used preplant or preemergence for the selected crop. Apply appropriate postemergence herbicides if weeds are present.
More effective herbicides are available for corn than for sorghum or soybeans.
See EC90-130, A Guide for Herbicide Use in Nebraska , for latest recommendations. If weeds are too large to kill with herbicides at planting, use shallow tillage to kill the existing weeds. Sweep plows, tandem disks or power driven rototillers have been used successfully. If used early, a no-till cultivator or power driven cultivator can save a field from weeds after crop emergence. In the undisturbed fields treated with herbicides prior to planting, weeds often emerge in the disturbed areas of the row and the marker.