Name: Rhagoletis indifferens

Alias: The Western cherry fruit fly looks similar to adult house flies, with a few distinctions. They are a little smaller and their bodies have thin white stripes across the abdomen. Their clear wings have thick, black bands running across them. The females lay their eggs exclusively in cherries. The larvae burrow deep into the pit of the cherry where it gets food and protection. Once the cherries are just about ripe so is the larva, and it finds his way back out again and falls to the ground where it will overwinter in the soil in the pupa form. Adults emerge from the ground around sometime in May, depending on weather conditions.

Crimes: Larvae feed inside of the fruit, giving it a definite “ew” factor. Their exit holes also cause the fruit to be unmarketable. In commercial orchards, there is absolutely no tolerance of cherry fruit flies. Populations can be sustained from uncontrolled home orchards.

Redeeming Qualities: They add additional protein to your shakes and pies.

Sentence: Once the larvae has been laid, there is nothing that can be done. Control methods must be entirely preventative. Sticky traps can be used to monitor when the adults emerge and how many are in your orchards. Mulches and fabrics underneath cherry trees can prevent larvae from entering the soil and completing their life cycle. For homeowners, pesticide options are limited to four categories: Spinosad, carbaryl, malathion and pyrethroids. They all come in different labels and bottles, so be sure to read and follow the label. Repeat applications may be necessary.

For more information on dangerous and beneficial bugs, call UI Extension educator Joseph Sagers at 208-745-6685 or email