Cabbage Root Maggot

insect

Delia radicum

Fly larvae that bore into roots of brassica crops, causing wilting and death.

Identification

Adult: small gray fly resembling housefly. Larvae: 1/3 inch white legless maggot in roots. Wilting seedlings.

Wilting seedlings. Tunnels in roots. Secondary rot. Stunted growth. Plants pull up easily with damaged roots.

Cardboard collars around stems at soil level. Beneficial nematodes. Row covers. Diatomaceous earth around stems.

Chlorpyrifos granules at planting (restricted). Spinosad drench.

Row covers at planting. Crop rotation. Fall cleanup. Delay planting until after first generation fly activity.

Data confidence: medium | Source: curated_ipm