If you’ve set foot in Pittsburgh lately, you’ve almost certainly been introduced to the spotted lanternfly — an invasive species from Asia first seen in Pennsylvania in 2014. Allegheny County is under quarantine along with 50 other counties in the Commonwealth. While reports indicate a decrease in lanternflies in central Pennsylvania, they’re everywhere in Pittsburgh.
Narcisi Winery and Restaurant’s director of operations Roberto Smiraglio lives in Fox Chapel.
“It's been a week that I've been everywhere, outside of my backyard in the front yard. There's hundreds.”
He’s talking about the spotted lanternflies, of course. It’s concerning to him because he manages a vineyard 10 miles north of the city. Grape vines are one of the plants lanternflies have been known to kill. He says it’s concerning, but his vineyard is still fly-free and safe, for now.
“I just checked in our vineyard,” he reported. “There's nothing, fortunately. Maybe it's just for now, but I know they can be very damaging.”
Spotted lanternflies don’t bite or sting people — they suck the sap of plants and trees like roses and other perennials, grapes, tree of heaven, maples, walnuts, birch, willows, sumac, and dozens of other species. They’re considered a plant stressor and, in combination with other stresses, can cause a lot of damage.
“They stick to the trunk of the vines,” Smiraglio said, “and they suck all the nutrients.”
It’s hard to say just how many lanternflies have descended upon Pittsburgh.
“We have no discreet scientific way to measure the size [of the population] other than treating it like a math problem,” said Penn State Extension horticulture educator Amy Korman in a recent email. “The population grows every year just based on the fact that a single female lays at least 35 eggs/egg mass.”
“There are a lot of females out there depositing egg masses,” she added.
Economists in Pennsylvania have estimated an unchecked infestation could cost the state $324 million annually. This particular infestation likely started in the city and is spreading outwards because the lanternflies — like so many invasive species — often hitch rides with people.
Sue Myers is the horticulture and conservation director at Pittsburgh Botanic Garden. She says they’ve been watching for years, but this is the first year they’ve spotted the lanternflies in the botanic garden. Apparently, they have a preference for young red maple trees, but Myers says they’re still only seeing very low numbers so far.
“We're looking every day, we're scouting every single day on other species in addition to the red maple,” she said. “But right now the numbers are so low, we're not even super worried about treatment. We will treat with a natural insecticide like neem oil if the numbers go up a little bit. But right now we can hand pick.”
Myers says she and others have also begun scouting for lanternfly egg masses and will continue through September. Destroying eggs is one way to combat the infestation, according to PennState Extension’s Spotted Lanternfly Management Guide.
Unfortunately, less than 2% of egg masses laid on trees are at a reachable height. But Myers is undeterred and stresses that it's important to stay vigilant and observant. She and other experts say another very important thing people can do is check their cars (doors, wheels, wipers, etc.) to make sure they aren’t taking lanternflies or their eggs on the road with them.
Health and science reporter Sarah Boden contributed to this story.
