Learn more about the Japanese beetle

Posted: Tuesday, July 5, 2011

Have you noticed something devouring your plant leaves? It could be the Japanese beetle, a serious pest of turf and 400 species of ornamental plants and trees including serviceberry, grapes, roses and basswood.

 

A brown and block beetle on a leaf.
Japanese beetle consuming a leaf.

Have you noticed something devouring your plant leaves? It could be the Japanese beetle, a serious pest of turf and 400 species of ornamental plants and trees including serviceberry, grapes, roses and basswood.

This non-native invasive insect was accidentally introduced from Japan and has no native predators. It feeds on leaves, flowers and fruits, causing aesthetic damage and possibly weakening a plant over time. Adult beetles are present from late July through September.

To help deter the Japanese beetle, consider these measures:

  • Reduce the size of your lawn to limit the population since the baby beetles, or grubs, live under the turf. To be effective, the hand picking of beetles or use of pheromone traps and chemical treatments must be carefully timed.
  • Consider planting species that are not susceptible to the Japanese beetle, like red and white oaks, red maple, balsam fir, Canadian hemlock, yew and others.

For more information, visit the U of MN Extension bug identification website at www.extension.umn.edu/gardeninfo/insectgallery/index.html.