Keyword Site Search

Cold Temperatures Don't Hinder Japanese Beetle
Infestations Can Cause Damage to Lawns and Plants


Japanese Beetles are a quarter-inch in size, with a green head and five white spots of hair on each side of their abdomen. They target over 400 plant and tree species, including turfgrass, and cause serious damage. Symptoms of a Japanese Beetle infestation are similar to what drought conditions can cause.

Japanese beetle infestations are not likely to be hindered during the cold weather temperatures, according to Donald Lewis, professor of entomology at Iowa State University. The beetles have adapted to winters and are likely to thrive once spring and summer arrive.

The Japanese beetle infestation began in 1926, when they were first discovered in New Jersey. Since their discovery they have been found in every state east of Mississippi. In Japan they are not considered a pest, because their natural predators control the population.

Grubs feed on roots of grass, which can produce symptoms much like drought does, and adults feed on foliage of more than 400 species. Well-irrigated lawns are likely hiding places for the grubs because the soil is soft and easy to move through.

In some areas, raccoon damage may signal the presence of the beetle, because they feed on the grubs living in the soil.

Efforts to battle the pest are being made throughout the country.

In Washington County, Ore., attempts have been made at full eradication prompted by an expected five-year infestation.

The infestation is the largest ever recorded in Oregon, with more than 23,000 beetles trapped in the treatment area, but leaving an unspecified amount outside of it. Because of this, the size of the treatment area is being increased.

Plans are being finalized to expand the treatment area and the number of beetles targeted. Some residents may be forced to get more treatments on their property, even if they had already participated in one of the treatment programs.

For now the best thing residents can do is cooperate with officials and eradication efforts and prevent the spread of the pest to neighbors.

Comment Box is loading comments...

August 24, 2019, 10:36 pm PDT

Website problems, report a bug.
Copyright © 2019 Landscape Communications Inc.
Privacy Policy