Apple Maggot

The Apple Maggot (*Rhagoletis pomonella*), a highly destructive fruit-infesting fly larva belonging to the fruit fly family *Tephritidae* under the order *Diptera*, is a major economic pest of apples and various pome fruits across North America. Often referred to as the 'railroad worm,' this pest is native to eastern North America, where it originally fed on wild hawthorns before adapting to cultivated apples. The adult fly is easily recognized by its distinctive banded wing patterns, but the damage is caused by the legless larvae (maggots) that feed silently inside the fruit, tunneling brown, winding trails through the flesh.

Identifying an apple maggot infestation involves checking ripening fruit for skin punctures and internal decay. The female fly leaves a tiny, pinprick puncture wound on the fruit skin when laying eggs, which turns into a small, dark, dimpled or sunken spot as the fruit grows. Slicing open an infected apple reveals the diagnostic 'railroad' damage: winding, brown, decaying tunnels running through the white flesh, caused by the feeding of the small (8 mm), translucent white, legless maggots. Heavily infested fruits turn soft, decay completely, and drop prematurely.

Apple maggots primarily attack cultivated apples and wild hawthorns, but they can also infest pears, plums, and other pome and stone fruits.

Apple maggots overwinter as pupae inside hard puparia buried 1 to 3 inches deep in the soil beneath host trees. In midsummer (June to July), adult flies emerge and feed on leaf secretions for 7 to 10 days before mating. Females puncture fruit skins to insert eggs singly, which hatch in 3 to 7 days, and the maggots feed for 3 to 4 weeks before emerging from fallen fruit to pupate in the soil, with one generation per year. Organic control focuses on hanging red sticky sphere traps baited with apple volatile lures to capture adult flies, collecting and destroying fallen fruit daily to prevent larvae from entering the soil, and using clay barriers (kaolin clay). Chemical control uses foliar spinosad or organophosphates. For complete fruit pest guides, browse our Plant Disease Identifier Hub, or explore similar fruit-boring profiles like Codling Moth, Plum Curculio, and Oriental Fruit Moth. For specialized diagnosis of related crop threats, see our guide on Cedar-Apple Rust.

To prevent extensive crop loss, orchardists must separate Apple Maggot infestations from other key fruit-boring insects. Apple maggots (often called railroad worms) chew winding brown decay lines directly through the flesh of apples and plums. Unlike the clean entry holes plugged with brown frass left by the codling moth, or the crescent scars characteristic of the plum curculio, apple maggots leave only microscopic skin punctures. Their larvae are headless, legless white maggots that pupate in the soil. The comparison table below provides a diagnostic reference to identify the pest: