Timing treatments for apple maggot (Diptera: Tephritidae) control using sticky sphere traps baited with synthetic apple volatiles

Weak relationships between larval damage and adult catch were observed for apple maggot, Rhagoletis pomonella (Walsh), in untreated dwarf, semidwarf, and standard apple trees, using fed sticky sphere traps baited with synthetic apple volatiles. Traps were sensitive in detecting adults. Fruit among the canopy quadrants were uniformly infested, which indicated that the baited traps were not causing an aggregation of the damage within the canopy. Studies using the baited traps for timing apple maggot control treatments in commercial orchards demonstrated that commercially acceptable levels of control could be obtained using a catch threshold of two adults per trap. Adult catches were not accumulated for the threshold until 12 d after a treatment. With this threshold, 46% fewer treatments (1.9 fewer applications) were applied than in a calendar-based program.