Some ways to prevent worm infestation in apples include pruning the apple trees and removing the litter and the fallen fruits from around the trees. Using insecticides is an easier method of preventing worm infestation.
Pruning the trees removes the branches that touch the ground acting as pathways that pests use to get to the fruits. It also makes it easier to clean up the litter under the trees. Placing sheets under the trees until all the apples have fallen blocks the pests from burrowing into the soil from where they become a nuisance the following season.
Since the fruits that fall prematurely are usually infested with worms, removing all the fruits that drop prematurely stops them from becoming breeding grounds for the worms.
Applying a registered insecticide to the apple trees and the surrounding field while paying special attention to the underside of the leaves and along the branches helps in controlling the worms. Follow the manufacturer’s instructions about the reapplication of the insecticide.