Monday, January 30, 2023
Jan. 30, 2023

Linkedin Pinterest

Traps, quarantine among efforts to slow Japanese beetles in Yakima Valley


YAKIMA — State officials made one thing clear about the Yakima Valley’s growing Japanese beetle problem during meetings this week: Battling the invasive pest will be a marathon, not a sprint.

Washington State Department of Agriculture officials hosted a virtual open house Thursday evening and reviewed the escalation of the Japanese beetles infestation in the Grandview area and elsewhere, including additional adult insects found in the Wapato area.

This followed a Tuesday in-person public hearing in Grandview, also viewable online, which discussed the rules and reasons for a potential 49-square-mile quarantine area in the southeast corner of Yakima County and a portion of western Benton County.

At both events, WSDA officials stressed the importance of containing and, hopefully, eradicating the problem.

“If the Japanese beetle becomes permanently established in Washington state, it could pose a significant economic threat to the state’s agricultural industries,” said Greg Haubrich, pest program manager for WSDA, at the quarantine public hearing.

First found in New Jersey in 1916, Japanese beetles will eat more than 300 types of plants, including roses, grapes and hops. The adult beetles damage plants by skeletonizing the leaves. Adults also feed on buds, flowers and fruit on the plants.

Quarantine could start soon

The quarantine was first proposed last year after 900 traps caught more than 24,000 Japanese beetles in and around Grandview. It would regulate certain items and impose restrictions on their movement out of the quarantine area.

Quarantined items could include soil, humus, compost, manure, grass sod, yard debris, potted plants, bulbs and plant crowns.

Attendees of Tuesday’s meeting had several questions about the proposed quarantine, which could be adopted next week and take effect on Sept. 9. Several people asked how long the quarantine might last.

“As long as we’re catching beetles, we’ll still be spraying (to kill larvae) and still be observing these quarantine rules,” said Camilo Acosta, the WSDA Japanese beetle eradication coordinator.

Acosta added that the quarantine would continue until there are two consecutive years with zero adult beetles found in the area. Surveys of Japanese beetle infestation will determine if the quarantine area needs to be expanded or changed.

“Every single year we’re going to use our surveys, our traps data, to re-evaluate our extermination and our quarantine strategies,” he added.

Melodie Smith, the Grandview resident who first found the pest eating her roses in the summer of 2020, said anything that would help prevent the spread of Japanese beetles needs to be enacted.

“I am in support of the quarantine. I think we need to do some heavy control here,” Smith said. “I don’t think we can wait another year. This is the third year I’ve seen them, and they just keep growing exponentially.”

In May, the Senske lawn care service company began spraying an insecticide to kill the beetles’ larvae in a 3,100-acre area centered around Grandview, Acosta said. He estimated there were 4,200 properties within the treatment area.

WSDA mapping specialists created a real-time detection map that growers will be able to use to determine if they are within a mile of a known WSDA Japanese beetle detection.

More pests found in Wapato

The WSDA detection map was updated this week as traps set up around Wapato were checked, said the WSDA’s Cassie Cichorz, who hosted Thursday evening’s virtual open house.

Through Thursday, 54 adult beetles were found in 15 traps near Wapato, all near the intersection of U.S. Highway 97, West Wapato Road/West First Street and the railroad tracks. A handful of Japanese beetles were first reported in Wapato last week, almost 30 miles from the infested area in Grandview.

On the other hand, no additional insects were found in traps set up in Richland, where exactly one adult Japanese beetle was found last week, Cichorz reported.

She urged residents in Grandview to follow the quarantine rules once they take effect because “the beetle is a really good hitchhiker,” transported by everything from airplanes, trucks and trains to soil, sod, potted plants and yard debris.

Each adult can lay 40 to 60 eggs annually, which produces extremely rapid growth in an area already reporting thousands of beetles, Cichorz said.

Besides the spring insecticide application (targeting larvae) and the proposed quarantine, the WSDA recently opened a Japanese beetle yard waste dropoff site at 875 Bridgeview Road in Grandview. Residents living in the infestation area in and around Grandview are asked to bring their yard waste there. The site is open from 7:30 a.m. to 3 p.m. weekdays, and there is no charge for disposal, the WSDA announced.

Cichorz said the WSDA has set about 2,300 traps for the beetles this year, and they will be checked every 7-10 days through mid-October, when the adult flight season ends.

Residents can help by setting their own traps, or simply picking off beetles by hand (they do not bite or sting), dumping them into a bag, and killing them with soapy water. Throwing a securely sealed bag of captured beetles into the freezer also does the job, she said.

“You can trap them yourself. Trapping adult beetles prevents them from going back into the soil and laying eggs,” Cichorz said. “And we’re really trying to count every single beetle, so if you see it, snap a picture and send it to us. If you can catch it, even better.”

She referred residents to the WSDA’s Japanese beetle website and the WA State Japanese Beetle Watch Facebook group for more information.