Pest Threatens Wisconsin Fruit Crops

An invasive fruit fly that has been spreading across Wisconsin since it first arrived five years ago has been confirmed in more than half the state.

University of Wisconsin-Madison fruit crop entomologist Christelle Guedot said the bug known as spotted wing drosophila has been confirmed in 40 counties and suspected in nine more.

“My suspicion is that it’s everywhere now in Wisconsin,” she said,

Guedot said the exotic fly has been taxing on fruit growers. But she said they’re learning how to manage its impacts on different types of fruit. Until recently, Guedot said growers had been advised to spray insecticides if they find the fly in traps set around their fruit.

“We are recommending to our grape growers that if they find flies now in their traps, it doesn’t mean that they have larvae in their fruit,” she said. “It doesn’t seem that the fruit is susceptible for the wine grapes that we tested unless it’s already damaged.”

Guedot said their findings might save some time and money.