Pear psylla problems are greatly lessened in unsprayed orchards, where they are heavily attacked by parasites. Infested fruits also are prone to spoilage. There are naturally occurring populations of apple maggot on the Western Slope. However, these strains restrict their feeding to wild hosts such as hawthorn and have never been observed to infest apples. Apple maggot injury to apple.
Apple maggots spend the winter in the pupal stage around the base of apple trees.
The adult flies emerge in midsummer, typically between mid-July and early August, and lay eggs on the fruit. There is only one generation per year. These traps are useful for timing sprays to control the insect, with sprays timed to coincide with periods when the flies are being captured. Furthermore, the use of several red sticky spheres per tree also can provide substantial control of this insect by killing adult females before they lay all their eggs. Spider Mites Spider mites can be serious pests of orchard plantings.