A REVIEW OF CHERRY FRUIT FLY: THE EASTERN USA PERSPECTIVE

A review of the literature indicates that the eastern cherry fruit fly and the black cherry fruit fly are the two most significant direct pests of cultivated cherries in eastern North America. Both species were classified as a single species until the middle of the 20^th century. Today, distinct differences between the two species have been demonstrated. Both cherry fruit flies have a similar seasonal biology: one generation per year throughout their geographic ranges. Damage to the fruit occurs in two ways, feeding by the adults and feeding by the larvae. Oviposition injury by the adult may occur, but the primary fruit damage results from the feeding of the larvae within the fruit. Fresh market and processed cherries have a zero tolerance for cherry fruit fly damage, and most growers apply preventative sprays of organophosphate insecticides to control them. The most effective method for monitoring both species is the use of baited, fluorescent yellow sticky board traps. These are not considered reliable enough at low densities to make pest control decisions. Traps are good indicators of first fly emergence, but they are not good indicators of the level of infestation. Therefore, chemical controls are applied to cover the activity period of the flies. Alternatives to chemical control of cherry fruit fly species have been attempted but with limited success. Degree-day models have proved reliable at predicting adult cherry fruit fly emergence. Insecticide treatments should begin within 5 to 6 days after the first fly emerges. A long-residual insecticide should be applied every 10 to 21 days until harvest is complete to kill adults before they lay eggs.