Canola-Cabbage maggot

Delia brassicae

Pest description and crop damage
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. Cabbage maggots damage and destroy root systems, riddling roots with tunnels when infestations are heavy. Tunnels provide entryways for pathogens that can cause blackleg and bacterial soft rot.

Management-chemical control

  • bifenthrin (Tailgunner, others) at 0.033 to 0.04 lb ai/a or 2.1-2.6 fl oz/a. May be applied at bloom. Do not exceed 0.08 lb ai/a or 5.12 fl oz per season. Do not apply less than 14 days apart.
  • thiamethoxam (Cruiser 70WS)-Do not use a Cruiser 70WS rate that will result in more than 0.266 lb thiamethoxam per acre (120.66 grams ai/a) per season.
  • zeta-cypermethrin (Mustang Maxx) at 4.0 fl oz/a (0.025 lb ai/a). PHI 7 days. Do not apply more than 24 fl oz of product (0.15 lb ai) per acre per season. Do not make applications less than seven days apart.