Cabbage root fly

Larvae are small, legless, white maggots usually less than 0.33 inch (8 mm) when full grown; their head end is pointed and the rear is blunt with a dozen short, pointed fleshy processes arranged in a circle around two brown, button-like spiracles. They are found feeding on feeder roots or boring into the taproot. Adults are dark gray flies about half the size of the common housefly; they lay their eggs in cracks in the soil near plant stems, and hatching larvae burrow beneath the soil surface to invade the roots. After feeding 3 to 5 weeks, larvae pupate in roots or surrounding soil. Adults may emerge from pupae within 2 to 3 weeks, or the pest may overwinter as pupae when conditions are unfavorable for development. There are at least two to three generations in cool, moist climates along the coast.