Japanese Beetles

margin: 8px 6px 0px 0px;">Picture of Adult Japanese Beetle, Courtesy of Clemson University USDA Cooperative Extension

Japanese beetles, Popilia japonica, are native to Japan, but have migrated to the U.S. They are common in every state east of the Mississippi, and have now spread as far west as California. Japanese beetle infestations can defoliate an entire tree in days. In Wisconsin, Illinois, Minnesota and Ohio, they have been an especially pervasive nuisance just before the 4th of July.

Japanese Beetle Adults vs. Grubs

Adult Japanese beetles are what most people think of. In most parts of the U.S., they emerge from the soil very early in summer (end of June) and feed for a few weeks, leaving destruction in their path.

margin: 4px 0px 0px 6px;">Picture of Japanese Beetle Grub, Courtesy of Whitney Crenshaw, Colorado State University, Bugwood.org

However, like the chicken and the egg, adults had to start life somewhere, right? That’s right, they start as larvae in the ground (grubs). While the adults are out feeding in early summer, the females are laying 40-60 of these buggers per season. Grubs chew grass roots and hang out through the winter until early the next summer – when they emerge as adults and start the cycle all over again.

How to Get Rid of Japanese Beetles

If you’re seeing Japanese beetles around, insecticide treatments can help you get rid of them. For adult Japanese beetles, the most popular products to help you get rid of them are:

margin: 4px 6px 0px 0px;">Xytect for Japanese Beetles Contains Imidacloprid Insecticide

Xytect – is a systemic insecticide that will help you get rid of Japanese beetles – along with a bunch of other nuisances, like emerald ash borer, aphids and more. Xytect 2F is applied as a foliar spray or as a soil drench. And the cool part is that a treatment of Xytect 2F can last an entire year!  See our video on How to Apply a Liquid Soil Drench – it’s not hard and it only takes 10 minutes.

margin: 4px 6px 0px 0px;">UpStar Gold Insecticide for Japanese Beetles

UpStar Gold – a spray applied insecticide designed to control a large group of shade tree pests, including Japanese beetles, caterpillars, gypsy moth, tent caterpillars and more, provides both contact AND residual control of these buggers. Spray it on and reapply as needed (but not more than once a week). See our video on How to Apply a Foliar Spray to Broadleaf Plants – it’s not hard to do it right all by yourself. The very economical quart size will yield 148-296 gallons of spray solution. Nice!

How NOT to Get Rid of Japanese Beetles

Whatever you do, no matter where you live, DON’T use Japanese beetle traps! All they do is attract more hungry adult beetles – more than the traps can keep up with. You’re just making things worse!

More Information on Japanese Beetles

The Tree Geek is the premier source for information on Japanese beetles. Not only for homeowners in Minnesota, Illinois, Wisconsin and Ohio, but all across the U.S.A. Here’s some more stuff to check out:

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