Kennewick included in Washington State Department of Agriculture's Japanese Beetle treatment area

KENNEWICK, Wash. – For the first time ever, Kennewick has been added to the area where the Washington State Department of Agriculture sprays for Japanese Beetles.

This year, the treatment area has increased to eight square miles in Pasco, including a small strip of land near the Columbia River in Kennewick.

Camilo Acosta, the Japanese Beetle Eradication Counselor for WSDA, says 15 to 20 properties will be treated.

“It’s just barely across the river where that expansion to the treatment area has gone.” Acosta said.

Japanese Beetles are highly invasive pests that were first found in Grandview in 2020. By 2024, the number of beetles trapped exceeded 26,700, with them being caught all around south-central Washington.

The beetles feed on over 300 different plants with both adults and larvae posing threats to farmers and community gardens. While adults skeletonize plants and leaves, larvae feed off the roots of plants.

“This passes an issue for Washington because in that list of threatened species of host plants are hops, grapes and corn, which just happened to be some of our major crops that we grow in the infested areas,” said Acosta.

The Washington State Department of Agriculture uses a variety of ways to capture and kill the beetles, including bag traps and spraying. The WSDA uses an insecticide called Acelepryn, who’s active ingredient, chlorantraniliprole, binds to the muscles of the beetle, resulting in paralysis and death. According to the WSDA, the insecticide is safe when used correctly, but you should still avoid contact with it.

In January, the WSDA said they mailed out over 17,000 letters seeking permissions to spray for Japanese Beetles on properties. Acosta says their complete eradication lies with getting consent from residents.

“This is a long-term process,” said Acosta. “We want to get as close to 100% of those treatment permissions as possible.”

Spraying for Japanese Beetles begins April, stretching into the months of May and June as well. To sign up for Japanese Beetle treatments, visit WSDA’s website here.