The bug often called “cherry fruit fly” is a tiny fly that lays eggs on ripening cherries. It’s also called the “cherry maggot“.
Generally, this happens end of May or beginning of June, and can last until July.
Refer to our guidance on how to effectively fight against cherry flies, and you’ll spare yourself the disappointment of seeing your cherry harvest ruined.
Symptoms of a cherry fruit fly invasion
From under the tree, it’s quite difficult to know whether the cherry fly is active or not. You’ll have to check on the cherries up close as soon as they start forming. Picking an infected one makes it easier to identify the pest.
- A small part of the cherry starts to turn brown and shrivels up.
- Tiny pinholes can be seen along the cherry’s skin and when pressed, juice squirts out through them.
- The fruit rots from the inside, and the cherry maggot hatched from laid eggs appears.
Sometimes, you only discover this little white maggot when you already took a bite from the cherry! Eww!
Which cherry tree cultivars are most hit?
Late-bearing cultivars are often harder hit than cultivars with early fruit fruit formation.
What does the cherry fly look like?
- Rhagoletis cingulata, the eastern cherry fruit fly, is found in central and eastern United States and Canada.
- Rhagoletis cerasi, the European cherry fruit fly, strikes only in Europe, including the United Kingdom.
- Rhagoletis fausta, the black cherry fruit fly, can be found in the entire United States and Southern Canada.
- Rhagoletis indifferens, the western cherry fruit fly, appears in the Western United States.
These all are about a quarter-inch (4 mm) in size and are hard to see on the trees. They hover in flight as they inspect cherries to lay their eggs in. The maggots start off tiny and nibble around the pit until they’re about 1/4th inch (4 mm) long.
Here’s a video that shows the cherry fruit fly
Best way to treat against the fly
- First of all, the most effective solution is to plant early varieties such as the ‘Bigarreau‘ variety, since the fruits mature before the fly has yet spread to become seriously invasive.
- Set up sulfate ammonium traps to attract the flies, also called pheromone traps.
- Spray a 100% organic selective insecticide.
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Smart tip about the cherry fly
Start harvesting your cherries as soon as the first ones are ripening. Since the cherry fly usually lays eggs in soft, ripe cherries, you’ll be depriving it of potential nesting spots, while ensuring you at least get some fruits for yourself!
While picking, immediately eliminate cherries that show signs of fruit rot, and spray your hands with alcohol or disinfectant to keep the disease from spreading.