Dingy Cutworm on Sunflowers (09/01/16)
Dingy Cutworm on Sunflowers
Dingy cutworms moths are being observed laying eggs on sunflower heads (and other Asteraceae species), especially along weedy field margins. They are active from now through September, even into October. The eggs will hatch into larvae (cutworms) that feed on the bracts of the head for two or three instars before dropping to the ground to overwinter in the soil. The feeding injury on sunflower heads is not economic and no control is recommended. Dingy cutworm larvae resume feeding in the spring, and that’s when economic losses can occur as spring crops are planted into these fields. So, please make a note of these fields because they usually have cutworm problems next year. Be sure to scout for cutworm feeding injury early next spring! See the 2016 North Dakota Field Crop Insect Management Guide for economic thresholds and insecticides registered for cutworm control in field crops.