Postemergence Control Selective postemergence herbicides are very effective for shattercane control. They control shattercane up to 18 inches tall. Shattercane should be controlled by 3 to 4 weeks after planting to prevent crop yield loss. If shattercane numbers are moderate to high, this early removal is especially important. Nebraska studies have shown that applications at half of the normal dosages required to control other weeds will control 4 to 6-inch shattercane.
Soybeans are an ideal crop to clean up shattercane.
Roundup applied with a wiper applicator, such as the rope wick, can effectively control shattercane escapes in soybeans and sorghum if the shattercane is 8 to 12 inches taller than the crop. Several applications may be needed. Exercise care to avoid Roundup contact with the crop, especially sorghum. Many postemergence herbicides can be spot applied to shattercane for significant cost savings and effective control of scattered plants. Apply these only in crops for which they are registered.