Western Cherry Fruitfly - Rhagoletis pomonella Walsh                                       Jerry A. Payne, USDA ARS, www.ipmimages.org HOSTS: Cherries and plums. DESCRIPTION: Cherry fruitfly maggot larvae are legless, 1/4 to 3/8 inch long larvae, creamy white in color except for 2 dark mouth hooks. Adults are housefly sized with darker patterned “W” or “Z” markings on clear wings. LIFE CYCLE: Adults emerge and move to cherry trees in late May through June depending on weather. They begin to lay eggs in developing fruit immediately. Eggs hatch and maggots feed near the cherry pit. CONTROLS: Biological: Birds prey on adult flies. Don’t put netting on trees (to keep fruit-eating birds out) until cherries start to ripen. Traps: Trap adult flies with yellow sticky card or red ball sticky traps. Put traps out in late May. Botanical: If you catch 2 or more flies per week on traps, spray pyrethrin or Spinosad. Cultural: Avoid water extremes and heavy nitrogen fertilization.
Missoula County Extension Office; Missoula, Montana 59808 - Updated for 2006