Why Japanese beetles are particularly bad this year

Japanese beetles decimate a leaf of a linden tree in Omaha.
Japanese beetles decimate a leaf of a linden tree in Omaha, Neb., July 20, 2017.
Nati Harnik | AP

If you think that you are seeing more Japanese beetles eating the plants in your garden this year, you're not mistaken. Entomologists at the University of Minnesota confirm that the destructive pests are thriving in Minnesota right now and the problem is only going to get worse.

University of Minnesota Professor Vera Krischik, one of the state's leading authorities on Japanese beetles, says climate change is partly to blame.

"These cold wet springs we usually have kill them, and if you think about it it's been getting warmer in the spring," Krischik said. "As long as it's above 50 (degrees), they can be active and feed on roots."

The bugs are about a half inch long with a dark metallic green head and tan wings. They particularly like roses, but they eat 300 kinds of plants and are not easily controlled with chemicals.

MPR News is Member Supported

What does that mean? The news, analysis and community conversation found here is funded by donations from individuals. Make a gift of any amount during the Winter Member Drive to support this resource for everyone.

"The problem with managing Japanese beetles as adults or as grubs is that they're in places where honeybees and native bees would forage," Krischik said. But she said, a new pesticide called Acelepryn (or GrubEx) is less harmful to bees.

Click the audio player above to hear the interview.

Video of a Japanese beetle trap