They have arrived!? Like a horror scene from an 80’s alien feature, the Japanese Beetle has descended upon my landscape. I hoped it would never happen, but living off a highway with frequent traffic between croplands and the industries of Kansas City has increased my likelihood of seeing pests sooner than I would like. While inspecting my front garden for insects and blooms, I saw the little green and gold beetles munching quietly on my oakleaf hydrangea. I quickly snapped a few photos before crushing them with my fingers.
The Japanese Beetle, a non-native pest of turf and ornamentals, was first introduced to the U.S. in 1916 in New Jersey. Since then, they have conquered much of the United States, save for 9 that are considered “beetle-free”. Here in Kansas, they are mainly a threat in the eastern areas and the south near Wichita. The discovery in my hydrangeas was the first time I have seen them in Brown County.
The adult beetles emerge from the ground after pupating in early July and spend their time feeding, mating, and laying eggs for nearly 2 months. The adults have a metallic green head and thorax with a gold to copper looking abdomen. There are 5 white tufts along each side of the abdomen and 2 white tufts at the end of the body. They start their feeding at the tops of plants and work downward, skeletonizing leaves and eating flowers. The females fly to the ground at night and deposit their eggs-they can lay up to 60 eggs each.
The larval stage, called a grub, lives in the soil, munching on roots after hatching. They can be a major pest of turf and lawns. They overwinter 2 to 6 inches below the soil surface. Grub control should be applied from Mid-July to September for best results. Our crews are currently applying grub control for a variety of white grub species, including Japanese Beetle.
To reduce the number of adults, the best method is hand picking. They can easily be squished between the fingers, but for those who are squeamish, shaking the adults into a bucket of soapy water will do the job nicely. This method also works well for blister beetles and shield bugs.
For more information or confirmation on if you have Japanese Beetles in your landscape, or for treatment for grubs in your lawn, contact us ASAP!