Root Maggots
Order: Diptera
Family: Anthomyiidae
Species:
Cabbage root maggot (Delia radicum)
Onion root maggot (Delia antique)
Seedcorn root maggot (Delia platura)
Root maggot
Pests as immatures
Appearance
Adults
- Gray, bristly flies, smaller than a common house fly
Larvae
- Whitish, fleshy, legless, wedge-shaped grubs
Symptoms
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
Biology
- Overwinter as eggs, nymphs and adults
- Many offspring, short-generation time, asexual reproduction
Control Options
Physical
- Protect with polyester-fiber row covers
- Aluminum foil collars
- Spray forcefully with a garden hose
- Yellow sticky traps
Cultural
- Proper nitrogen fertility
- Compost culls
Biocontrol
- Conserve natural enemies
- Mass-releases from commercial insectaries
Pesticides
- Check the Database of Pesticides Registered in Idaho (Kelly Database) for pesticides registered in Idaho
Caution: Read Pesticide Labels
Pesticide labels override other recommendations.