Season’s First Stink Bug Wave In Valley Reported

HARRISONBURG — A pest that’s crept into the Shenandoah Valley in droves in recent years doesn’t appear to have any intention of going away on its own.

This year’s first “big wave” of the brown marmorated stink bug, an insect native to East Asia accidentally introduced into the United States in 1998, showed up in Winchester on Sept. 21.

The pest is of particular concern to orchard operations as the bug sucks out the juices of fruit on trees, causing it to rot and making it unsalable. The bug also may damage other produce, such as sweet corn and tomatoes.

Entomologists at Virginia Tech’s Alson H. Smith Jr. Agricultural Research and Extension Center take a daily survey of the number of stink bugs and the numbers aren’t looking promising.

On one day late last month, the team counted about 1,300 of the pests at one site in Winchester at 3 p.m., which isn’t even their peak hour, according to entomologist Chris Bergh.

“At 4 or 5, it probably would’ve been at least double that,” he said.

This first wave was right on time relative to last year, but with a greater number of bugs.

“We’re not quite sure why we’re seeing more bugs … this year than last year,” Bergh said, but he noted that the high count in Winchester doesn’t necessarily correlate to stink bug populations in the Harrisonburg area.

Local Take

But local residents are reporting problems similar to those experienced since the pest first surfaced in alarming amounts in 2010.

Patrick Spinosa, manager of the Harrisonburg PermaTreat branch, said his office has been getting up to 10 calls every week about stink bug overload.

“Last year was a little bit worse, but this year is still pretty bad,” he said. “[The calls] really started pouring in probably” in late August.

But the bugs will start dying quickly after the first frost.

“I don’t see it lasting longer than October,” Spinosa said.

The pests have ravaged through some local crops, including the orchards at Turkey Knob Apples
in Timberville.

The bugs have ruined about 1 to 2 percent of Turkey Knob’s product the last two seasons, according to President Jaime Williams.

That doesn’t amount to a major problem, but Turkey Knob might be more on top of insecticide spraying than other, smaller growers, he noted.

“Hopefully, we can get these things off the trees before they do do something,” Williams said.

Researchers across the country are working on just that. They’ve found a number of other bugs that prey on the pest, including wheel bugs, the praying mantis and certain spiders.

“But I don’t think at this point those predators are impacting the [stink bug] population in any substantial way,” Bergh said.

The best long-term prospect for getting rid of the stink bug problem locally is by systematically releasing parasitic wasps native to the Asian countries where the stink bug originated, he said.

But that likely won’t happen for several more years, he added.

“There are very specific rules and regulations regarding the release of nonnative species,” Bergh said. “We don’t want to introduce [species that are] going to cause other problems.”

Contact Candace Sipos at 574-6275 or csipos@dnronline.com