Cherry Fruit Fly 1 : Effects of Environmental Factors on Densities of Pupae

Abstract

Soil samples from a cherry orchard heavily infested with pupae of the western cherry fruit fly, Rhagoletis indifferens Curran, showed significantly fewer (40%) pupae on the west side of the tree than the other 3 sides. Yields of fruit fly pupae/929 cm 2 sample (0–3.04 m radii) ranged from an average low of 0.7 at 305 cm (10 ft) to a high of 8.4 at 152 cm from the trunk. Fruit fly populations in soil beyond the canopy of the tree (avg 1.3) were only 25% those under the canopy (avg 5.1). Tree size (large or medium) made only slight differences in the density patterns of cherry fruit fly pupae.