Clover seed-Sweetclover weevil

Sitona cylindricollis

Pest description and crop damage Adults are gray or brownish gray and about 0.25 inch long. Weevils feed on and notch foliage. Most severe damage is to seedling plants. Sweet clover is the primary host, but weevils also attack alfalfa and have been found on Ladino clover.

Management-chemical control

  • bifenthrin (Bifenture EC, Brigade 2EC, Capture 2EC, Discipline 2EC, Fanfare 2EC, Fanfare ES, Tundra EC) at 0.06 to 0.1 lb ai/a. Do not apply while bees are present. Do not make more than 3 applications per crop year. Allow at least 21 days between treatments. REI 12 hr. Do not graze clover after application. Do not cut treated clover for hay or forage. Do not use harvested seed for sprouting. No part of the treated field, including seed, seed screenings, hay, forage, or stubble, may be used for human or animal feed. Processed seed must be labeled. 24c SLN: OR-960021, OR-040039, OR-070013, OR-170012, ID-900006, ID-080011, ID-040009, ID-070009, ID-060023, ID-130004, WA-040027, WA-070015.
  • chlorpyrifos (Lorsban Advanced) at 1.0 lb ai/a. This product is highly toxic to bees. Do not apply when any clover bloom is present. Do not make more than one application per crop year. REI 24 hr. Do not graze clover after application. Do not cut treated clover for hay or forage. Do not use harvested seed for sprouting. No part of the treated field, including seed, seed screenings, hay, forage, or stubble, may be used for human or animal feed. Processed seed must be labeled. 24c SLN: OR-090010. Oregon only.