Rhagoletis pomonella (Walsh)
Adults are black flies with three (males) or four (females) white cross bands on the abdomen, a prominent white spot at the posterior end of the thorax, and the wings are marked with black bands in the shape of an "F" (A). The cream-colored eggs are laid singly under the skin of the fruit. The larva is a milky white, legless maggot without a distinct head but with a pointed front tip (B).
Widespread and a major pest in most fruit-growing states and provinces in eastern North America, but more of a problem north of the mid-Atlantic states.
Attacks apple mainly; may be found in European plum, pear, and cherry. On the surface of the fruit, oviposition causes punctures that appear as small reddish spots (C), which are sometimes accompanied by a white deposit. The larva digs brownish trails (D) in the flesh of the fruit.
The apple maggot can be confused with the cherry fruit fly (Rhagoletis cingulate) and the black cherry fruit fly (Rhagoletis fausta). These insects do not attack apples and can be distinguished by the patterns of their wing bands.
Sticky red sphere or yellow board traps can be used for monitoring of adults to detect potentially damaging numbers; intensive trapping to reduce numbers to acceptable levels may be practical in small plantings. Remove unsprayed apple trees within 100 m. Apply protective insecticides, if necessary, in mid- and late summer.
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