The signs of cherry fruit worms are often, malformed, shrunken, or shriveled fruit. Often, the cherries are rotten and pulpy and holes appear in the fruit. The worms are tapered, yellowy white, legless, and about ¼ inch long, or smaller.
These are the worms of the adult flies. The adult flies are about half the size of common houseflies, are black with dark bands on their clear wings. The adult flies appear in the late spring for about a month and they lay eggs in the cherries through holes they puncture in the skin of the fruit. The eggs then hatch into maggots that tunnel through the fruit. The mature maggots then drop to the ground and burrow into the soil to pupate. In the spring, they emerge from the soil as mature flies.
It is impossible to control the worms during the current season’s fruit, but they can be prevented or reduced over the year. In the spring, place Apple Maggot Traps out to capture the mature flies. The apple maggot trap and lure will work to attract and control the flies. The traps should be placed out early in the spring, around mid-April, as the flies lay their eggs during the late spring and early summer period in the new fruit.
Also as soon as the flies appear, spray the area with Bug Buster Pyrethrin Insect Spray. Repeat the process every seven days, or so. You can also reduce the spread of cherry fruit worm larvae by collecting and removing any fruit that falls to the ground.