Pest description and crop damage The adult is small, shiny black, and wasp-like. Larvae feed within the seed and destroy it.
Remove chaff piles and screenings and destroy or bury before the first of April. Cutting and removing hay the first week in June greatly reduces seed chalcid populations. Remove volunteer and waste-area red clover plants, which act as a reservoir for the pest.
East of the Cascades post-harvest harrowing followed by irrigation has been used to control infested seeds left in field at harvest. Fall disking that buries seed at least 1 inch reduces adult emergence. Rotation with a non-host crop (anything that is not a legume seed crop) helps control this pest.
No labeled insecticides are effective.