Codling Moth Larvae
Adults: graybrown moths; forewings with fine, white lines and brown tips, hindwings brown with pale fringes (3/4-inch wingspan). Larvae: pink or creamy white, 7/8-inch caterpillars with brown heads. Eggs: flattened, white. Found throughout North America.
Larvae tunnel through apple, apricot, cherry, peach, pear, and plum fruit to center, ruining the fruit.
Overwintering larvae pupate in spring; adults emerge when apple trees bloom. Females lay eggs on fruit, leaves, or twigs; larvae burrow into fruit core, usually from blossom end, for 3 to 5 weeks, then leave fruit to pupate under tree bark or in ground litter. Two to three generations per year, 5 to 8 weeks apart.
In early spring, scrape off areas of loose bark to remove overwintering cocoons and spray horticultural oil at a dormant-season dilution; grow cover crops to attract native parasites and predators, especially ground beetles that eat pupae; hang one codling moth trap per dwarf tree (up to four traps per large tree) and maintain it according to manufacturer's instructions; apply kaolin clay to deter egg-laying and prevent larvae from entering young fruits; cover fruits with nylon barriers before they reach 1 inch diameter; check trees weekly and remove and destroy any infested fruit; trap larvae in tree bands and destroy daily. If you've had past severe problems with codling moth, apply spinosad two or three times, 10 to 14 days apart beginning when the first codling moth eggs hatch. For subsequent generations, apply a single spray at the beginning of each new egg hatch. In large orchards, use monitoring traps to determine main flight period for moths, then release parasitic Trichogramma wasps to attack eggs.
Codling moth adult photo: Clemson University - USDA Cooperative Extension Slide Series, Bugwood.org
Codling moth larvae photo: Gyorgy Csoka, Hungary Forest Research Institute, Bugwood.org