- Eggs: Tiny, elongate, oval, slightly curved, pearly white eggs, usually laid at soil surface singly or in small clusters, near seeds, sprouts, or decaying organic material.
- Larvae: Yellowish-white maggot with a sharply pointed head and tough skin, about ¼" long at maturity (after completing 3 instars).
- Pupae: Oval, light reddish-brown to dark brown puparium, in the soil.
- Adults: Grayish-brown fly, about 1/5" long.
- Pupae overwinter in the soil. Adult flies emerge in March and April and are attracted to the odor of decay.
- Flies feed on flowers of many plants, and are most active feeding and laying eggs around mid-day.
- Flies are attracted to and lay their eggs in sprouting or decaying seeds and plants, organic fertilizers such as fish meal or cottonseed meal, and freshly tilled soil.
- Hatched larvae burrow about 2-3” into the soil, where 1st instars feed on decaying organic matter, and later instars additionally feed on seeds and seedlings. Larvae pupate in the soil.
- There are 2 to 4 generations annually in Maryland.
- Corn primarily. Also asparagus, beans, beet, cabbage, cucumbers, melons, onion, potatoes, radish, squash, spinach, turnip.
- Seeds never germinate, or when you dig up seeds they are damaged or have a white maggot is inside.
- Most common on warm–season crops with large seeds such as corn, bean, pea, and melon.