Pest description and damage Peach twig borer is a European insect first found in California in the 1880s. It is a major pest of apricots, peaches, plums, and prunes. There are no native hosts outside the orchard. The adult is a steel-gray moth with white and dark scales, about 0.33 to 0.5 inch long. The mature larva is approximately 0.5 inch long, with a dark brown head and distinctive, alternating light and dark bands on the body. The pupa is smooth and brown. The larva of the borer causes injury to both fruit and twigs. Feeding on the buds and twigs occurs early in the season; later the larva bores into the shoots, causing a characteristic "flagging" or wilting of the new growth. Later generations of larvae feed on shoots or fruit causing blemishes.
For biology, life history, monitoring and management
See Table 4 in: