April 1993 Integrated Crop Management is published by the Department of Entomology , Iowa State University , Ames, Iowa. Because insect damage sometimes occurs below the soil surface, it may be difficult to determine the need for an insecticide. Seedcorn maggots are minor soil pests that sometimes cause stand loss by feeding on the germinating seed. There are no rescue treatments for this insect, so you must apply insecticides at planting time if economic damage is anticipated. Seeds are at greatest risk for injury when animal manure is spread on the soil or when live, green plants are killed in the spring and incorporated into the soil prior to planting.
Damage is more likely to occur during a cool, wet spring when germination is delayed.
Fields that only have last years crop residue on the soil surface or are no-till fields should not have problems from seedcorn maggots. Germinating seeds alone are not sufficient to attract seedcorn maggots to the field. A seed treatment is not necessary if a soil insecticide is being used for corn rootworms. Read and follow all label directions before using any insecticide. This information subject to a usage policy .