How to Get Rid of Japanese Beetles on a Birch Tree


The invasive Japanese beetle damages a range of plants, including the birch tree, where it likes to feed on the upper leaves exposed to full sun. Adult Japanese beetles, just under 1/2 inch long with a metallic green body and coppery brown wing covers, leave behind their signature skeletonized leaves where they have fed. Since these pests spends ten months of the year in the turf, it is most effective to treat Japanese beetles grubs in the ground. Reserve pesticide use for when damage from beetles has been documented over two or more years and when beetle numbers become excessive. To best get rid of Japanese beetles on a birch tree, start underground.

Step 1

Cut four evenly spaced samples in the turf in early spring from where you suspect adult beetles have emerged. Use a hand trowel to cut a 6-by-6-inch square on three sides. Pull back the turf and examine the top 2 inches of soil. Count the number of eggs present in each 6-inch square area. If you find two to three per square, plus obvious damage to the turf, proceed with chemical treatment.

Step 2

Apply imidacloprid, a long-lasting reduced-risk insecticide, in mid to late June, before eggs hatch into grubs.

Step 3

Follow up with a treatment of trichlorfon in July if the area is highly infested. Forty-eight hours before applying the chemical, water the area with 1/2 inch of water to bring feeding grubs closer to the soil surface.

Step 4

Water the area with a 1/2 inch of water immediately after the chemical application to encourage the chemical to flow down to the root zone.

Step 5

Continue to water the treated area every four to five days so the trichlorfon can work properly.

Tips and Warnings

  • Japanese beetle traps may do more harm than good, according to the University of Illinois, because the traps attract more beetles to the area than they capture.

Things You'll Need

  • Trowel
  • Imidacloprid
  • Water hose
  • Trichlorfon


  • Utah State University Extension: Utah Pest Fact Sheet: Japanese Beetle
  • University of Wisconsin Extension: Japanese Beetle
  • University of Illinois Extension: Japanese Beetles
Keywords: eradicate Japanese beetles, control Japanese beetles, beetles on birch

About this Author

Ann Wolters, who has been a freelance writer, consultant, and writing coach for the past year and a half, has had her writing published in "The Saint Paul Almanac," and in magazines such as "Inventing Tomorrow" and "Frontiers." She earned a master’s degree in English as a second language from the University of Minnesota and taught English as a foreign language for nearly seven years.