Canola-Cabbage seedpod weevil

Ceutorhynchus asimilis

Pest description and crop damage A seed weevil, small and gray with a snout. They congregate as adults on flowers. They eat three seeds per larvae in the pod, reducing yield to as low as 30% of potential yield. They also vector Alternaria leaf spot on the pods, which is common in Canada and moving into the Palouse region of the PNW.

Management-chemical control

  • cyhalothrin gamma (Declare, Declare II) at 0.015 lb ai/a. PHI 7 days. Do not apply more than 0.045 lb ai/a per acre per year.
  • deltamethrin (Battalion 0.2 EC, several others) at 0.009 lb ai/a. PHI 7 days. Retreatment interval 7 days. Do not apply more than 0.018 lb ai/a per season.
  • imidacloprid (Gaucho 600F, Gaucho 480) seed treatment at10.24 to 25.6 fl oz/hundredweight of seed. PHI 45 days when applied as seed treatment.
  • lambda-cyhalothrin (Warrior II, several others) at 0.015 to 0.03 lb ai/a. Do not apply more than 0.09 lb ai/a per season. Do not apply within 7 days of harvest.
  • methyl parathion (Cheminova Methyl 4 EC) at 0.5 lb ai/a per application or 1.0 lb ai/a per year. Do not make more than 2 applications per year. PHI 28 day. REI 4 days. Do not graze treated fields or feed treated for age or threshings to livestock. Make first application when two or more insects can be found per plant on young pods. In Washington: This product cannot be applied to blossoming canola except under the following conditions: 1). The field to be treated is at the end of the blossom period with no more than 10% bloom remaining. 2). The application may only be made in the evening from three hours before sunset to midnight, and only if bees are not for aging In the field to be treated at the time of application and are not expected to be for aging on the treated field for the remainder of that day.
  • zeta-cypermethrin (Mustang Maxx, several others) at 0.025 lb ai/a. PHI 7 days. REI 12 hr. Do not apply more than 24 oz. or 0.15 lbs ai per acre per season. Do not make applications less than 7 days apart.