They pupate in late May to June and adults start emerging in late June to mid-July. Adults which live from 30 to 45 days, feed through late summer or early fall. Grubs first feed on decaying matter but soon feed on roots as they move deeper to an overwintering site. Adults are the principal injurious stage to peaches, although grubs may injure nursery stock. Adults may occasionally skeletonize leaves, but fruit feeding is the most common injury to stone fruits.
Adults are gregarious and often feed in groups chewing large chunks from the fruit.
In the mid-Atlantic area most injury occurs during the last two weeks of July through the first week in August. Fruit is usually injured during the last two weeks before picking. Adults may be monitored by quietly moving into the tree, jarring several branches, and observing how many fly off. Direct fruit counts are the most effective way of assessing damage. Fruit should be examined by the method outlined for other insects.