Invasive Fruit Fly Poses Problem For Wisconsin Berry Growers

An invasive fruit fly that’s been spreading across the state since it first arrived five years ago is causing some growers to abandon their berry crops or seek other options.

Christelle Guedot, a University of Wisconsin-Madison fruit crop entomologist, said that spotted wing drosophila has been confirmed in 40 counties and suspected in seven more. She said the exotic fruit fly is especially taxing on organic growers.

“They’re struggling even more than conventional growers because there’s few insecticides that organic growers can use,” said Guedot.

Guedot added that the insecticides the producers are able to use are often expensive.

She said some growers are abandoning plans to plant raspberries, which are more susceptible to the bug, but that others are looking at ways to keep the fly out.

“A lot of people are doing research for high tunnels, for example,” said Guedot. “Not so much on just covering your raspberries, because of the picking in the middle of all that. You have to remove it to pick.”

Guedot recommends planting raspberries that bear fruit in the summer rather than the fall.

Correction: The original version of this story said that spotted wing drosophila had been confirmed in 16 counties. It has actually been confirmed in 40 counties.