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The codling moth is the most common insect to attack apples, but it will also attack other fruit trees such as pears and nut trees, including walnuts. When a tree is attacked by codling moths, the fruit is blemished by small holes surrounded by dead tissue. A small sawdust-like material is often found around the holes made by codling moth larvae. Small brown-headed, pinkish-white worms about an inch long are often found in fruit that has been infested by codling moths.
In the spring, close to when the tree is in blossom, the mature codling moths can be seen flying around the tree, most active late in the day, at twilight. In the spring, the mature moths lay their eggs on leaves, twigs, and developing fruit. When the eggs hatch, the larvae emerge and begin to tunnel into the fruit. After feeding for a few weeks, they emerge and will quickly lay a second generation of eggs, in mid-summer. Due to the multiple generations over the season, the fruit can be damaged throughout the season.
Once the worms have penetrated the fruit or nuts, it is impossible to kill them. To protect uninfected fruit and nuts, at the first sign of the moths in the spring, spray with Borer-Miner Killer every seven to ten days, throughout the growing season. Remove any fallen fruit from the ground.
Use BioCare Codling Moth Traps to determine the presence of Codling moths and the need to spray, as well as to reduce the moth population. Normally, two traps per tree are recommended.