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Carrot Rust Fly

Order: Diptera
Family: Psilidae
Species: Psila rosae

Pests as larva (maggot in soil)


  • Adult: slender metallic-green fly
  • Larvae: 1/3-inch long wiry, legless straw-colored "worm"

Host plants

  • Carrots
  • Parsnips, celery, parsley, dill, caraway, coriander, fennel


  • Rust-colored root rots
  • Wilting and stunting above ground


  • Overwinter as pupae in soil, larvae in roots
  • 2-3 generations per year

Control Options


  • Floating row covers over seed beds


  • Late-planting (after mid-June) to avoid oviposition
  • Harvest by late September
  • Destroy culls
  • Eliminate alternate host plants
  • Rotate beds


  • Natural larval and pupal parasite


Contact Us

Integrated Pest Management

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

Phone: 208-364-4046