AILSA CHANG, HOST:
Stomp, squash, smash or otherwise destroy spotted lanternfly. That was the advice from agricultural officials in many states where the flies were detected over the summer, and for a few months now, people have answered the call. But the insects are still here. They have spread to 14 states so far, and fall is egg-laying season. It's also the grape harvest in Virginia, where winemakers are trying to guard their vines from the invasive pests. From member station Radio IQ, Roxy Todd reports from one vineyard in central Virginia.
(SOUNDBITE OF GRAPE JUICE BUBBLING)
ROXY TODD, BYLINE: Inside the wine cellar at Loving Cup Vineyard, grapes ferment inside wooden barrels.
(SOUNDBITE OF GRAPE JUICE BUBBLING)
TODD: Within 20 miles of this winery, there have been three recent sightings of spotted lanternflies. out in the grapevines, owner and winemaker Karl Hambsch says he thinks it's just a matter of time before the bugs make it to his property.
KARL HAMBSCH: Because it is comfortable on so many different host plants, I think it's going to be in everyone's backyard.
TODD: Spotted lanternflies originated in China and were discovered for the first time in the U.S. in Pennsylvania in 2014. In the last few years, they've spread to states, including Virginia, where one of their favorite host plants, tree of heaven, grows abundantly. Hambsch even finds the trees popping up in his vineyard.
HAMBSCH: I can try to pull this out, but I probably won't get it all, so I have to come and dig it out.
TODD: Spotted lanternflies are about an inch long. They're mostly gray with black spots and have distinctive red wings. They burrow into grape vines and eat the sap. Since agricultural officials put out the call to kill the bugs, people have come up with creative ways to do that and posted them online. In this TikTok post, a woman smashes a handful of lanternflies with a plastic chicken.
(SOUNDBITE OF TIKTOK VIDEO)
UNIDENTIFIED PERSON: I caught 20.
TODD: In another video, a man burns lanternflies with a propane torch.
(SOUNDBITE OF PROPANE TORCH BLASTING)
TODD: But researchers say squishing them is just as effective and safer. It's not clear how much trying to control spotted lanternflies has cost wineries. When the bugs first arrived in the U.S., vineyards in Pennsylvania were hit hard. Doug Pfeiffer, a professor at Virginia Tech who studies the bugs' impact on growers, says the pest took everybody by surprise.
DOUG PFEIFFER: So it reached very high numbers and caused severe impacts in vineyards, including cases of vine death.
TODD: Estimates for economic losses due to uncontrolled spotted lanternfly in Pennsylvania alone have been as high as $324 million a year, but that hasn't come to pass. Once researchers studied the bugs for a few years, Pfeiffer says they figured out how to prevent the worst of the damage, especially to grapes.
PFEIFFER: But it's at the expense of greatly increased insecticide use.
TODD: Spraying insecticide is costly, and Pfeiffer is concerned that several years of heavy pesticides could kill bugs that actually protect grapes from disease. Back at Loving Cup in Virginia, Karl Hambsch says insecticide isn't an option for his vineyard because they're organic. So Hambsch is asking people to check their cars to make sure spotted lanternflies aren't hitchhiking on them.
HAMBSCH: They'll fly to land on your car, and they will just sit there behind your bumper. And then when you're at the rest stop or at your location, they'll hop off and do their thing.
TODD: He's also passing out cards to everyone who visits his winery to show what lanternflies look like. Meanwhile, researchers with the USDA are studying another way to control the insects. In a few years, they may introduce parasitic wasps that eat them. These wasps occur naturally in China and help control lanternflies there. For NPR News, I'm Roxy Todd in Albemarle County, Va. Transcript provided by NPR, Copyright NPR.