Spotted lanternfly spreads, threatens Pa. fruit and timber crops

Darvin Levengood walks the grounds of his Berks County winery. The spotted lanternfly arrived in Berks in 2014 and has spread to five other counties.

Darvin Levengood can only wait.

On a bright Wednesday morning, at the Manatawny Creek Winery, which he co-owns in Amityville, there was an 8-foot metal fence around one of his vineyards to keep peckish deer from snacking on his grapes and nets draped over some of his rows to keep the birds’ aerial assaults at bay.

For now, however, he has no recourse for an invasive species known as the spotted lanternfly, or Lycorma delicatula, an insect native to Asia that first arrived in the United States in Berks County in 2014 and has spread to neighboring counties. The pest is a potential threat to the state’s $13.1 billion annual production of apples, grapes, peaches, and other crops, as well as $16 billion in timber and wood products, according to the Pennsylvania Department of Agriculture.

But Rich Blair, owner of Blair Vineyards in Kutztown, says the spotted lanternflies he first discovered on his property two years ago have multiplied exponentially.

“There’re thousands of them,”  Blair said. “They’ve hatched maybe two or three months ago into nymphs; now they’re transitioning from nymphs into mature adults, which fly.” He said the hoppers are plentiful on their favored Tree of Heaven.

Camera icon Holly Raguza, Pennsylvania Department of Agriculture
An adult spotted lanternfly, with wings spread, showing its colorful hind wing. Photo by Holly Raguza, Pennsylvania Department of Agriculture

“You can see maybe a thousand insects on each Tree of Heaven,” Blair said. “And each one of those will be a mature adult in a week or two.” The Tree of Heaven is the bugs’ preferred host for feeding and reproduction.

Camera icon Lawrence Barringer, Pennsylvania Department of Agriculture
Lateral view of an adult spotted lanternfly. Photo by Lawrence Barringer, Pennsylvania Department of Agriculture

Blair said his vineyard is about two miles from where the bugs first arrived in the states. He said he has done what he can to control them, but containing the insects is tricky, delicate work because some insecticides can kill unintended targets.

And spraying can feel futile, considering the pest’s prodigious reproduction.

“And so, you know, you just wait for the next episode,” Blair said.

So far, damage from the inch-long, spotted black, red, and white lanternflies — now in Berks, Chester, Montgomery, Bucks, Lehigh, and Northampton Counties — has been small-scale, giving farmers and state agricultural officials time to plan their fight. A quarantine of the affected areas has extended every year since the pest was first sighted. On Friday, the state Agriculture Department added an additional 21 towns in those counties to the quarantine list.

“Spotted Lanternfly has proven to be a tremendously destructive pest that spreads rapidly and can be devastating to our valuable grapes, hardwoods and hops,” said Agriculture Secretary Russell Redding in a statement. He urged anyone seeing the insects to report sightings to badbug@pa.gov.

“Last year, we saw a couple but nothing to really worry about,” Levengood said. “This year, we have seen more […] but nothing here at our vineyard that I would term ‘critical.’ ”

Camera icon Jessica Griffin 
Steuben grapes, in Amityville, Berks County, Pa., Wednesday, Aug. 9, 2017. Pennsylvania agriculture officials added another 21 towns on Friday, Aug. 11, 2017 to the quarantine area for the invasive Asian insect known as the spotted lanternfly, an area including parts of Berks, Bucks, Montgomery, Chester, Lehigh and Northampton counties. These pests threaten destruction of grapes, apples, peaches, hops, nursery stock and timber stands. 

The insects feed on crops and release a viscous ooze known as honeydew, which coats leaves with a sheen and eventually provokes the growth of sooty ash, which blackens the leaves, preventing photosynthesis, according to Sven-Erik Spichiger, the entomology program manager at the state Agriculture Department.

“It’s a very serious pest,” Spichiger said. “We’re not sure just how [bad] the impact is going to be, but the damage is certainly visible to the naked eye when you’re in the area.”

Camera icon Jessica Griffin
Darvin Levengood walks the grounds of his winery, keeping an eye out for the spotted lanternfly, but does not see any, in Amityville, Berks County, Pa., Wednesday, Aug. 9, 2017. The nets on the trees are to keep birds away from the grapes; they would not prevent a lanternfly infestation.  

Though the Levengood family’s 87-acre property near Douglassville in Berks County is not yet overrun with the pests, Levengood views infestations at growers to his north as harbingers of what may lie ahead for his winery.

No spotted lanternflies were visible Wednesday morning on a Tree of Heaven — which Levengood calls “their favorite haunt” — or on the neighboring wild grapevines that crawl along the base of the trees, another favorite of the pest.

“They’re hiding really well,” Levengood said. “I’m assured we have a few, but we are not inundated with these critters like some of the people to the north and east of us.”

Levengood doesn’t expect his luck to last.

“I absolutely anticipate it getting worse,” he said. “It’s gradually spreading more and more.”

Those who live and work in the quarantined areas are directed to avoid moving outdoor objects like firewood, vegetation and yard waste, lawnmowers, and grills — anything that the insects could potentially hitch a ride upon. Vehicles, trailers, and other mobile equipment should be inspected before they are moved outside the quarantine areas.

Federal and state agencies have joined in the fight to contain the lanternfly’s spread since December 2014, three months after the Berks sighting. The USDA has granted a total of $5.5 million for the state’s containment efforts. Joining the state Agriculture Department are the state Department of Conservation and Natural Resources and Penn State Extension.

Amy Korman, an educator with Extension’s Montgomery County office, says public information is a key focus, along with working as “the interface between science and industry.” As she explained, “We take science-based research and make it understandable to growers.”

Before they can eradicate the pests, Korman said, researchers are having to get more familiar with the species.

“There’s a lot about the biology of this insect that we don’t really have a full grasp of,” Korman said. “The big picture of what the total impact will be — they’re still kind of sorting out those things.

“We’re kind of peeling this back, layer by layer,” he added.

Spichiger said initial U.S. research focused on South Korea’s experience and research from 2006, two years after the insects landed on the peninsula from China, Vietnam, and India, where they are native. Officials said the lanternflies in South Korea have attacked 25 plant species that also grow in Pennsylvania.

Previous experience with other invasive insect species — including the brown marmorated stink bug and gypsy moths — is helpful to state agriculture officials dealing with the spotted lanternfly.

“We also weren’t completely caught with our pants down, frankly, because we had something called gypsy moth blow through starting quite some time ago,” Spichiger said. “In fact, this insect acts very similar.”

Stink bugs in 2010 caused “severe losses” for some of Pennsylvania’s peach and apple orchards. The pest — native to China, the Korean peninsula, Japan, and Taiwan — arrived in Allentown in 1998 and eventually spread to 49 Pennsylvania counties. They’re still as much an issue as ever, Spichiger said.

For the lanternfly, current research is focused on the insect’s anatomy in the hopes that a weakness in the pest can be found and manipulated. Scientists are working with various pesticides, predators, and parasitoids, Spichiger said, including a parasitic wasp that “might infest a spotted lanternfly and cause it not to reproduce.”

In the meantime, control efforts are aimed at mechanical removal, including uprooting Tree of Heavens — itself an invasive species — scraping away lanternfly egg masses over the winter and wrapping trees with sticky bands to trap nymphs.

State agriculture officials in Maryland, Delaware, and New Jersey have expressed concerns about the insect’s possible spread, a potential threat to their multimillion-dollar fruit crops. Maryland’s peach and apple orchards were valued at $12.2 million in 2015, and in New Jersey, the two fruit crops were valued at more than $60 million in 2016, according to the New Jersey Department of Agriculture.

In Boyertown, Steven Frecon, the owner and orchard manager of Frecons Farm, was not in the quarantine area until this year. His farm grows apples, peaches, cherries, and berries. He saw his first spotted lanternfly this spring in nymph form.

Since then, “they have gotten to a level that I’m now concerned about the size of the population,” Frecon said.

And he has doubts about the efficacy of a quarantine, especially because the bug can fly, albeit poorly, and hop from treetop to treetop.

“It’s not going to stop the bug from continuing the spread in temperate climates, like Pennsylvania, Maryland, New Jersey, Ohio, New York,” Frecon said, “That’s where it’s headed, and it’s going to keep moving in that direction.”