Biology ofBracon cephi(Gahan) (Hymenoptera: Braconidae), An Important Native Parasite of the Wheat Stem Sawfly,Cephus cinctusNort. (Hymenoptera: Cephidae), in Western Canada

During the past 25 years the wheat stem sawfly,Cephus cinctusNort., has become one of the most destructive pests of wheat in the Prairie Provinces. Annual losses in the wheat-growing area of Saskatchewan have been estimated as high as 17 million bushels (King and McDonald, 1944). There are, however, several native parasites of this pest, and of theseBracon cephi(Gahan) [Microbracon cephiGahan] is the most important. In some areas this parasite has been very effective in reducing severe sawfly infestations.