A variety of traps with attractive odors have been used to capture adult apple maggots,Rhagoletis pomonella(Walsh), (Howitt and Conner 1965, Neilson 1960, and Still 1960). However, the beneficial Tachinidae that are parasitic on some orchard pest insects and others are often attracted to these traps (Moore 1969). Therefore, when traps were hung in apple trees at 10 locations (1 trap/tree) on Washington Island, Wis., and used to monitor adult populations of the apple maggot, the collections were also checked for captures of other Diptera. The trap was a modified double-wing trap developed by Howell (1972) for use against the codling moth,Laspeyresia pomonella(L.) that is commercially available (Pherotrap IC®). The bait, (ca. 15 ml) Maggottract™ I Bait, was exposed on cotton wicks placed inside a plastic vial.