What is eating my apples?
Colin Collins, by email
Stefan says: You say there was powder on the surface and when you wiped this away, you found a hole and wonder what caused it. These are the classic symptoms of attack by codling moth and what you found is the exit hole where the caterpillars have left the fruit to pupate. If you look carefully, you will probably find another hole, by the eye of the apple, where the pest entered after hatching from eggs laid by the tiny female moths.
This is almost certainly the most common garden pest of apples but, sadly, there is little that can be done about it. Chemical sprays are not worthwhile and although pheromone traps are sometimes recommended, they’re used mostly by commercial growers. Encouraging garden birds which will feed on the caterpillars is far more valuable.