Corn Earworm – Vegetable Crops Hotline

Corn Earworm

Corn earworms are flying. I had 10 in my pheromone trap this morning (June 20). With the surrounding dent corn in most areas far from producing silks, the threshold for spraying silking sweet corn is 1 moth per night, well below what we are catching. So growers who have sweet corn with fresh silks are in danger of suffering serious losses if they don’t control the earworms. Because of problems with resistance to the pyrethroid insecticides, the best products available are Coragen® and Radiant®. Note the limitations on the number of applications or amount of product allowed. You may need both products to complete management on a particular planting. Begin spraying when 30-50% of the plants in your field are silking. Continue to spray every 3-5 days until the silks turn brown.

To see corn earworm trap catches around the state, go to

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