The life cycle of the crucifer flea beetle is summarized in the graphic to the right. The crucifer and striped flea beetle are the dominant species feeding on these plants. Click to expand The crucifer flea beetle is the most widely distributed and destructive flea beetle attacking canola, mustard, and rapeseed. Adult crucifer flea beetles are uniformly black with a metallic bluish sheen. The striped flea beetle is less abundant except near the northern edge of the agricultural region in Canada.
Adults are black with distinctive yellow stripes on their elytra.
Click to expand Click to expand Each species has a single generation per year, although adults appear twice during the growing season. In the spring, over-wintered adults emerge and feed on canola seedlings. In the fall, it is the offspring of the overwintering adults that are observed feeding on canola leaves, stems and seed pods. Flea beetles over-winter as adults near the surface of the leaf litter, grass, and debris beneath hedges, shelterbelts, poplar groves, and in association with canola stubble and volunteer cruciferous plants. The leaf litter begins thawing in the spring between late April and early May, but it will take another five to 11 days before the first flea beetles become active.