Japanese beetles typically arrive in the Ozarks area around mid-June or July. Experts say these beetles can defoliate more than 300 different types of ornamental landscape plants, but there are ways to protect yours.
Horticultural specialist Kelly McGowan with the MU Extension in Greene County? says Japanese beetles are non-native species that likely arrived on ornamental plants from elsewhere in the world.
They’re bright green—and even if you don’t see them right off the bat, McGowan said they feed in a particular way that makes them easier to notice.
“The Japanese beetle feeding kind of skeletonizes the leaves. So, even if you don’t see the beetles, you may notice some leaves of your landscape plants skeletonized. And that is a pretty classic sign that that is Japanese beetle feeding damage,” McGowan said.
Although McGowan said the beetles are unlikely to kill a plant, they can leave it looking pretty sad.
She says you can hand-pick the beetles off of the plants when the first adult beetles arrive, and drop them into a bucket with a few inches of soapy water. This helps the problem early, as the first beetles usually communicate withothers and tell them where to feed.
But it may be too late for that.
Traps can be effective if multiple neighbors are using them, or if they’re placed about 50 feet away from the plant you wish to protect.
Ultimately, McGowan said the best defense to Japanese beetles is choosing ornamental plants they’re not attracted to.
Some of their favorites to attack are roses, willows, elm and cherry trees, Japanese and Norway maples, and plum trees.