Skip to main content Skip to navigation
Washington State University

Composting Rotten or Homegrown Apples

Apple Maggot

We’re trying hard to stop the spread of the apple maggot, but we need your help. Natural spread of the maggot is quite slow—but people moving fruit spread the pests faster. The problem is usually homegrown, backyard fruit and not commercial fruit. Commercial fruit already has many restrictions on its production and movement to make sure it is pest-free.

Something we can do to help is to NOT compost infected fruit. This way, we can ensure that the bugs do not live. You can tell if your fruit has maggots, if it turns brown and mushy. Fruit damaged by the apple maggot will show feeding and bacterial damage throughout the fruit. This is differed than from a more common apple pest, the codling moth, which burrows straight to the core, feeds, then exits the fruit. The codling moth leaves most of the fruit undamaged.

The adult flies of the apple maggot are ¼ inch long, with a very distinctive wing pattern and three to four white stripes on their lower body. The flies first come out of their resting stage in the ground early in July, most are out by early August, but then continue emerging into September.

Adults are usually found near their host plants (apple, crabapple and hawthorn), feeding on honeydew or searching for mates and for egg-laying sites on the fruit.

The female lays the eggs just under the skin of the fruit, leaving a small dimpled mark. Eggs are laid one at a time in smaller fruit such as hawthorn berries, but several eggs can be laid in something as large as an apple. The eggs hatch in two to ten days, depending on temperature.

Apple Maggot Damage

Once they hatch from the eggs, the small white, legless maggots begin burrowing throughout the fruit in a random pattern. Depending on temperature, a maggot spends from 20 to 30 days inside the fruit, feeding and growing. The nearly mature maggot, which is about ¼ inch long, leaves the fruit, drops to the ground, burrows into the soil and inch or two, and develops into the resting or pupae stage.

If you find fruit that appears to have damage from the apple maggot, bag it securely in plastic bags and send to a landfill. DO NOT COMPOST!