Japanese Beetles

Japanese Beetles, what are these pesky insects?


Japanese beetles are a dynamite in a small package. They are small pests that are a big nuisance and threat to your landscape. They eat just about everything. They are classified as a pest to hundreds of different species. They are one of the biggest insect pests in the Eastern and Midwestern US. These pests rack up a steep bill for the gigantic damage they do to landscapes and crops each year. They are native to Japan and were first documented in the US in 1919. Upon their arrival to the US they have since spread across the country wreaking havoc on just about everything.

Identifying Japanese Beetles


Japanese Beetles are ½ inch in length and metallic blue-green with tan wings, with small white hairs lining each side of the abdomen. They lay eggs in the soil during June, which develop into tiny white grubs. These grubs will remain under wraps for about 10 months and overwinter and grow in the soil. They emerge from the soil as adult beetles and begin feeding in June. They usually attack plants in groups, which is why damage is so severe. Although the life-cycle of the adult Japanese beetle is barely 40 days, it can cover a lot of ground. They leave leaves looking like they are “skeletonized”, meaning only the veins remain on the plants. This is these easiest tell-tale sign you have a Japanese Beetle problem.


How to treat the problem of Japanese Beetles?

  • Call Roanoke Landscapes and let our experts help you diagnose and treat your problems.
  • Try to select plants that Japanese Beetles will not be attracted to. See our list of best and worse plants (posted below) for Japanese Beetles.
  • In the grub stage of late spring and fall (beetles have two life cycles per season), spray the lawn with 2 tablespoons of liquid dishwashing soap diluted in 1 gallon of water per 1,000 square feet. The grubs will surface and the birds will love you. Spray once each week until no more grubs surface.
  • Unfortunately, the most effective way of getting rid of Japanese beetles is to hand pick them. It’s time consuming, but it works, especially if you are diligent.
  • You can also purchase parasitic nematodes (most garden centers have them) and drench the soil around the area where you have the problem.
  • Neem oil and sprays containing potassium bicarbonate are somewhat effective.
  • Put down a drop cloth and, in the early morning when they’re most active, shake them off and dump them into a bucket of soapy water. They will not survive.


(lists taken from the http://www.almanac.com)


-Least favored by adult Japanese beetles and less susceptible to destruction.

  • Ash
  • Boxwood
  • Burning bush
  • Dogwood
  • Hemlock
  • Holly
  • Magnolia
  • Northern red oak
  • Redbud
  • Red maple


-Most favored by adult Japanese beetles and more susceptible to destruction.

  • American linden
  • Apple
  • Apricot, cherry, peach, and plum
  • Birch
  • Crab apple
  • Crape myrtle
  • Japanese maple
  • Norway maple
  • Pin oak
  • Rose

If you are plagued with a beetle infestation please do not hesitate to call us here at Roanoke Landscapes.



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s