Darrell Blackwelder: Japanese beetles are pillaging our plants

Published 12:00 am Sunday, June 30, 2019

It’s the time of the season and Japanese beetles are pillaging our plants. Gardeners have complained that the pests are damaging roses, crape myrtles and other flowering plants including vegetables.

These beetles have a wide host range, feeding on more than 275 different types of trees, shrubs and vegetable plants.

One of the most recognizable insects, the Japanese beetle is oval, just under 1/2 inch long with a metallic green body and copper colored wings. The insect plays dead when disturbed for a few seconds and then resumes its normal activity.

Insecticides such as Sevin can be applied as a dust or a liquid for immediate control; however Sevin is highly discouraged due to toxicity to pollinators, especially honey bees.

Japanese beetle traps can be implemented as an alternative control method, implementing a pheromone (sex attractant) that attracts the insect to the trap.

Research has shown that Japanese beetles are attracted to bright colors, especially “John Deere” yellow. Unfortunately, the traps attract more beetles to the very plants you are trying to protect.

Hand picking the beetles is another method of control if the beetle population is not too large. Fortunately, most damaged plants recover soon after the initial invasion.

Go to https://content.ces.ncsu.edu/japanese-beetle-1 for more detailed information.

Darrell Blackwelder deblackw@ncsu.edu is the retired horticulture agent with the North Carolina Cooperative Extension Service in Rowan County.