What is an Apple Maggot

Apple maggot is a pest that is a threat to commercial and homegrown fruit, especially apples. Apple maggot is native to the northeastern states where their primary host was hawthorn fruit until European settlers introduced apples to the region. Now apple maggot has spread throughout much of North America, threatening fruit crops from coast to coast. 

While several counties in Washington (primarily in Western Washington) have been quarantined, not all counties in Washington have apple maggot. Most noteably, most of central Washington's prime fruit growing region remains pest free. 

Photo: Joseph Berger, Bugwood.org

Adults
Apple maggot adults look like small house flies with striped wings, though they are really fruit flies. They primarily fly and lay their eggs in July and August in Washington. Apple maggot females make a tiny puncture in the apple skin and lay their eggs just under the surface. While the initial damage is easily overlooked, the damage eventually leads to dimpling of the fruit surface.

Larvae
In only 3-7 days, apple maggot larvae eggs hatch and tiny apple maggots emerge. The leggless maggots are about 1/16 of an inch long and a creamy white color but grow to about 1/4 of an inch long at maturity. The maggots eat and tunnel their way through the fruit, leaving brown trails behind. 

When apple maggots are mature, they exit the fruit and drop to the ground. They overwinter as pupae in the soil, emerging the next summer as adults, starting the cycle over again.