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Root Maggots

Order: Diptera
Family: Anthomyiidae
Cabbage root maggot (Delia radicum)
Onion root maggot (Delia antique)
Seedcorn root maggot (Delia platura)

root maggot
Root maggot

Pests as immatures



  • Gray, bristly flies, smaller than a common house fly


  • Whitish, fleshy, legless, wedge-shaped grubs


Above ground

  • Wilting (especially during dry weather), yellowing and stunting

Below ground

  • Root feeding, tunnels, secondary root rot

Increased susceptibility

  • Seedlings
  • Cool wet springs
  • High organic matter in soil


  • Overwinter as eggs, nymphs and adults
  • Many offspring, short-generation time, asexual reproduction

Control Options


  • Protect with polyester-fiber row covers
  • Aluminum foil collars
  • Spray forcefully with a garden hose
  • Yellow sticky traps


  • Proper nitrogen fertility
  • Compost culls


  • Conserve natural enemies
  • Mass-releases from commercial insectaries


Contact Us

Integrated Pest Management

Mailing Address:
University of Idaho Boise
322 E Front St, Suite 180
Boise, ID 83702

Phone: 208-364-4046

Fax: 208-364-4035