Adult beetles are 6 mm long with a rough-surfaced brown body and a distinctive snout. There is typically one genera-tion per year. Adult beetles overwinter in leaf litter and become active during late bloom, laying eggs in berries as the fruit starts to expand. The most distinctive sign of plum curculio infestation is the crescent-shaped slit and scar created when a female lays an egg into the side of a young berry. Scouting for this scar immediately after fruit set can indicate the level of infestation. Injured fruits color prematurely and may drop off the bush before harvest, avoiding contamination of harvested fruit. In early varieties, larvae may be harvested with berries.

Half-moon scar from curculio injury.

The egg develops into a white maggot with a brown head, which grows for two weeks inside the berry before leaving the fruit and burrowing into soil to pupate. In northern areas, adult weevils emerge in one month and seek overwintering sites; in southern areas, some will seek fruit to lay eggs for a second generation. Infestation is typically greatest near woods and at field borders.