On Crops: Apples, pears, walnut, quince
Worldwide in temperate climates
The codling moth is a small mottled brown moth about 1 cm in length. Adult moths are seen from late May to mid July. They lay their eggs on developing fruits, mainly apple and pear but sometimes walnut and quince. The eggs hatch into small white larvae with brown heads that burrow into the fruits and feed on the core. In late summer the larvae tunnel out of the fruit and fall to the ground where they overwinter in leaf litter. The following spring, they pupate and then emerge as adult moths in late May.
Where the larva has fed inside the fruits, they cause brown tunnels that contain the larva’s excrement. The larva’s exit hole is usually visible on the opposite side to the stalk on affected fruit when they are ready for harvesting.
Pheromone traps are commercially available and can be used to attract and contain adult male codling moths when they emerge during late May. Sticky paper rings can also be placed around the base of trees to trap newly emerged moths as they climb up the trees.
Codling moth larvae cannot be controlled once they have burrowed into a developing fruit. Apples that show obvious wounds or oozing holes should be picked, chopped and composted to interrupt the life cycle of this pest. Enclosing perfect green apples in clear plastic sandwich bags will protect them from codling moths and other pests.
Collecting and disposing of fallen leaves from around affected trees in the autumn will expose codling moth larvae to insectivorous birds and other predators.