Since that time, this insect has spread throughout the U.S. and southern Canada.
Damage is greater in cold, wet weather and when the seed is deeply planted.
Sprouting seeds of several vegetable crops are attacked by this seed infesting maggot. It injures sprouting corn, but is much more likely to damage beans and peas. Cabbage, turnip, radish, onion, beet, spinach, and potatoes may also be attacked. Attack is most severe when cool, moist, spring conditions contribute to slow germination and emergence. Occasionally, they also winter as maggots in manure or about the roots of clovers.