They’re everywhere. On trees, buildings and sidewalks, climbing walls and even cruising the waves of Peconic Bay.
Recognizable by their gray, black-spotted wings, which open to reveal a flash of red, spotted lanternflies are being seen across the North Fork. Sightings are often met first with disgust, then with a swat or stomp, as awareness has grown about the threat posed by the invasive pest.
Neither a fly nor a moth, although it resembles both, the spotted lanternfly, or Lycorma delicatula, threatens grapevines with its destructive habit of piercing plants and sucking out their sap. Strictly a sap feeder on trees and shrubs, it does not feed on leaves or fruit.
But there is hope.
The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) is studying the possible release, perhaps as soon as next year, of a tiny parasitic wasp known as Dryinus sinicus. Harmless to people and domestic animals, the wasp is a natural enemy of the spotted lanternfly and has the potential to put a significant dent in its population.
“From our testing to date, we have found Dryinus sinicus to be highly host-specific to the Spotted Lanternfly, showing strong preference for the fly,” said Hannah Broadley, an entomology biological scientist at APHIS who has been developing biological controls since 2018. “Additionally, field studies in its native range indicate that D. sinicus can parasitize (infest) 23–60% of SLF nymphs, demonstrating substantial natural control. Together, these findings indicate that D. sinicus has strong potential as an effective and targeted classical biological control agent for the fly in North America. The aim is to use this as a tool for long-term suppression and lessen reliance on repeated pesticide applications.”
Dan Gilrein, an extension entomologist at Cornell Cooperative Extension of Suffolk County in Riverhead, said scientists have investigated other potential biological controls.
“There have been some other biological controls investigated for managing spotted lanternfly. Some insect-killing fungi, for example, have been tested (and some even found killing lanternflies ‘in the wild’ on their own). So far, these have not been as reliably, consistently or highly effective as hoped but there may be ways of making them work better.”
Gilrein acknowledged that the SLF, as he referred to it, is here to stay. Populations, he said, tend to drop significantly over time, usually after two to three years.
“I hope the same happens around Long Island as well. Reports I have had from NY City seem to bear this out. The insect doesn’t totally disappear and there may still be some areas with high numbers, but overall, the levels in the region have dropped over time after the initial surge, which we are in now in Riverhead. It may be that other natural enemies, like birds, are now recognizing spotted lanternflies as prey and a food source. I expect the biocontrol if and when it is released will also help keep lanternfly populations at a low level.”
Local orchards and vineyards are coping well, he added, and have not yet seen high numbers of spotted lanternflies. But it’s a different story for homeowners and landscape professionals.
“Many people have reported large numbers in and around their properties especially in Riverhead and west,” Gilrein said.
Rather than using pesticides, Cornell has been encouraging Long Islanders to vacuum up lanternflies with a shop or backpack vacuum when they find them congregating on trees and buildings, as they tend to do this time of year. Egg-laying begins in mid- to late September.
“We also reassure people that lanternflies aren’t dangerous, don’t bite people or pets, don’t invade homes or structures (except accidentally) and can’t live for long indoors,” he said. “They also don’t damage structures. And there is no need to report sightings of them any longer. We and the NY Dept of Agriculture and Markets know they’re well-established in the region since 2017.”
Long Island Farm Bureau president Laurie McBride said the invasive species can weaken plants to the point that they do not have enough reserves to survive the winter. And, like ticks, she said, lanternflies were not wiped out by last winter’s record snowfall.
“The snow cover actually insulates them in the first 6 to 8 inches of soil so there was no good die off. They’re here to stay.”
McBride said she does not believe there was much crop loss this season.
“You would need a lot of them to be on one plant to cause damage.” But with the population increasing over the past two years and working its way east from Riverhead, she said next season’s crops could face a greater threat.
Many lanternflies flock to the tree of heaven, itself a nonnative species on the North Fork. McBride described it as a fast-growing deciduous tree native to China and Taiwan. Lanternflies gather and reproduce on its trunk and branches.
“This tree is the primary food source and it uses it for reproduction with inconspicuous eggs that look like mud slime. Their next targets are grape vines and then hops plants.”Among the roughly 70 types of plants that attract spotted lanternflies are orchard crops and maple, birch and willow trees.
McBride described as almost “sci-fi” the way the parasitic wasp, which is smaller than a housefly, could attack and kill lanternflies.
“The wasps would lay its eggs on the lantern fly and kill it from the inside.”
She said the larvae feed on the lanternfly’s fluids and tissues, consuming the host from the inside out.
A black-and-white sign outside the True Value hardware store on Main Road in Jamesport may best capture how frustrated North Forkers have become with the insect invasion.
“Lantern fly season, because mosquitos weren’t enough.”
The line was penned by cashier Katie Sorady, who said she came up with it after comparing the insects she encounters at home in Westhampton with those she sees at work.
“It’s all mosquitos and then I come up here and it’s all lanternflies! I was trying to think of a way to incorporate the two into the sign.”
Most of her customers have encountered spotted lanternflies, she said.
“They ask what products I have but right now I don’t have anything.”
Sorady said Dawn dish soap mixed with water and sprayed on the insects “weighs them down and kills them.” Neem oil also seems to work and is safe for trees and plants, she added.
Janet Mastropolo, who regularly swims in Peconic Bay near her Laurel home, said she once encountered hundreds of lanternflies floating alongside her.
“It doesn’t impede my swimming whatsoever, but it’s just gross that there are so many on top of the water.”
Gilrein theorized that because spotted lanternflies are not strong long-distance fliers, they can be carried offshore by winds and find themselves unable to return to land.
“Two years ago there were reports of numerous dead ones being found along some of the NYC area ocean beaches and last year I heard complaints around late August of many annoying beachgoers along the Sound in the Jamesport area.”
Despite the striking numbers being reported in parts of Riverhead and farther west, Broadley said the infestation has not yet reached the same level farther east.
“Although SLF presence on the North Fork is still limited, current indicators show expansion, and vigilance remains essential to protect one of New York’s most valuable agricultural regions. USDA and partners continue collaborating with Cornell Cooperative Extension and local industry to ensure early detection, rapid reporting, and science-based intervention.”
