Apple Maggot—Rhagoletis pomonella
Apple maggots cause two types of injury: "dimpling," and tunneling. Dimpling occurs around the site where eggs are laid, causing the flesh to stop growing, resulting in a sunken, misshapen, dimpled area. Tunneling, done by the larvae (maggots) eating in the fruit, causes the pulp to break down, discolor, and start to rot. The tunnels are often enlarged by bacterial decay. Damaged fruit eventually becomes soft and rotten and cannot be used.
The apple maggot fly is about l/4-3/8 inches long. It has a black abdomen. Females have four white bands on the abdomen. The smaller males have three bands. The wings are clear but are marked with black bands.
Female apple maggot flies deposit eggs singly just below the skin of an apple or other host fruit, leaving a small but visible puncture in the fruit which can lead to "dimpling."
The tiny cream-colored larvae (maggots) feed in the fruit. Maggots are about 3/8 inches long. The damage they cause resembles a series of brownish, irregular tunnels called railroading.
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Identification and Control Information
- Fact Sheet: Apple Maggot (PDF)—Cornell University Insect Diagnostic Laboratory
- Apple Maggot: Scourge of Home Apple Production (PDF)—University of Wisconsin
[Photos, left to right: Joseph Berger, Bugwood.org; H.J. Larsen, Bugwood.org; E.H. Glass, New York State Agricultural Experiment Station, Bugwood.org]