Fighting codling moth

The codling moth Cydia pomonella is the main enemy of the apple tree. This 16 to 18mm moth (lepidotera) also attacks pear, walnut, peach, quince, and apricot trees. What is the codling moth's lifestyle? The adult is a discreet, well-camouflaged, gray-brown moth with striped wings adorned with a characteristic reddish-brown spot, flying at dusk. It appears between April and June depending on the region. If the weather conditions are favorable, the female can lay between 50 and 100 eggs on the leaves or fruit the day after mating. About two weeks later, the larvae (caterpillars) are born and penetrate inside the fruit. The larva, measuring 1.5 mm long, is initially white in color and then becomes pinkish with a dark head. For 1 to 2 days, they wander around the tree looking for fruit (wandering stage). They dig a spiral tunnel towards the heart of the fruit and devour everything, even the seeds! The damage is often significant and the wormy fruit falls prematurely. The larva goes through 5 successive stages to reach a length of about 20 millimeters. At the end of summer, the larva leaves the fruit and takes refuge in the bark or in the soil or in the apple storage area to spend the winter in larval form after having spun a whitish cocoon (hibernating stage). Some enter diapause until the following spring, the others then transform into chrysalides and then into butterflies. The development cycle lasts 3 to 4 weeks. A second generation lays eggs around mid-July and causes even more damage! In the south of France, there is even a 3rd generation! How to fight codling moths? In the fall: Encourage the enemies of codling moths by installing nesting boxes for tits near fruit trees. In the spring: In May, bag each fruit in a light kraft paper bag, also called a fruit sleeve or cover, and tie it with an elastic band or a piece of string. Remove the bags about a month before harvesting to allow the fruit to color. Spray a maceration of wormwood or rhubarb every 10 days, before the butterflies emerge. From April to June, place a pheromone trap on each fruit tree or on a tree in the center of an infested area. Pheromones are volatile substances secreted by female codling moths to attract male butterflies. The goal is to trap males to limit mating and egg laying. Starting in June, place a corrugated cardboard trap strip on the tree trunk to encourage the larvae to form a cotton ball. Check for them every 15 days. Remove and burn it to eliminate future codling moths. Repeat this process in September to eliminate the second generation of larvae. Only remove the trap strip after the late October harvest. In summer, collect any wormy fruit that has fallen or remained in the tree and destroy it before the worm emerges from the fruit. This will interrupt the development cycle. In autumn, control the codling moth with nematodes from September to November to eliminate overwintering larvae. Nematodes are small, microscopic worms. They kill the larvae by penetrating inside and multiplying. They dissolve in water and are applied by spraying on the trunk and the ground under the shade of the tree to be protected.