Spotted lanternfly: New York’s newest insect invasion

Spotted lanternfly with wings open (photos by Lawrence Barringer |

If you live in or frequently visit a rural area of New York, chances are that you’re already on the alert for signs of our state’s better-known invasive insect pests: the hemlock wooly adelgid, the emerald ash borer, the venerable gypsy moth. Well, the Department of Environmental Conservation has recently announced a new six-legged peril to look out for: the spotted lanternfly (Lycorma delicatula), a most unwelcome immigrant from East Asia.

First discovered in the US in 2014, the spotted lanternfly (SLF) has already established a destructive presence in eastern Pennsylvania and spread into New Jersey, Delaware and Virginia. This critter is a brilliant hitchhiker, laying its inconspicuous egg masses on nearly anything from tree trunks and rocks to firewood – a known hazard to transport on account of the ash borer – and even vehicles. So it’s only a matter of time before SLF becomes a problem in our state, DEC proclaims. The first specimen found in New York, in the fall of 2017, was a dead insect in Delaware County. In 2018, SLFs were reported in Albany, Monroe, Yates and Suffolk Counties.


Here’s the deceptively good news about the SLF: Its favorite food is tree of heaven (Ailanthus altissima), itself an invasive species whose Chinese name, chouchun, literally means “foul-smelling tree.” The ailanthus spreads determinedly from suckers, thrives in harsh urban environments and has been variously nicknamed tree of hell, ghetto palm and stink tree. So, introducing an insect that can control it could be a good thing, right? Probably not, in fact. If you’ve ever seen Mark Lewis’ hilarious 1988 documentary Cane Toads: An Unnatural History, you’ll know that these amphibians were imported to Australia in an effort to control beetles that were devastating sugar cane crops. Not only did the toads fail in their mission, but they soon overran Queensland, where they have no natural predators, and became a bigger environmental scourge than the beetles.

Spotted lanternfly with wings closed

The problem here is that, while SLFs like ailanthus best, they also like to eat almost everything else. They are known to feed on the sap of more than 70 plant species. Fruit trees and grapevines are being especially hard-hit in Pennsylvania. Hops are also a favored host, as are nut trees. So this creature’s imminent arrival in the Hudson Valley, with its agricultural economy, is cause for serious concern. Residents are being asked to keep a sharp eye out for signs of its presence.

A live adult lanternfly is an eye-catching sight. Approximately an inch long and half an inch wide at rest, its forewings have black spots against a grayish background that may appear opalescent in their closed position. But it’s the hindwings that are truly striking: The lower portions are red with black spots, the upper portions dark with a white stripe. When the insect spreads them out to take flight, the bright flash of red is hard to miss. The adults begin to appear in July.

Much tougher to spot are the egg cases, laid in the fall. They’re about an inch long, smooth and brownish-gray with a shiny, waxy coating when first laid, brown and scaly as they dry out over time. Other telltale signs of an infestation are sap oozing or weeping from tiny open wounds on tree trunks, which appears wet and may give off fermented odors, and the accumulation of honeydew secreted by the insects, which can build up into sticky masses and become covered with a sooty-looking mold, harmful to photosynthesis and causing significant damage to the host plant. If you see something suspicious, take photos of the insect, egg masses and/or infestation signs, including something for scale such as a coin, and e-mail them to or fill out a reporting form. Be sure to include the location (address, intersecting roads, landmarks or GPS coordinates).

Efforts to stem the SLF tide into New York State are already underway. DEC is working with the Department of Agriculture and Markets and the US Department of Agriculture to conduct extensive trapping surveys in high-risk areas throughout the state, as well as inspections of nursery stock, stone shipments and commercial transports from Pennsylvania. A Department of Agriculture and Markets quarantine has been issued that restricts the movement of goods into New York from specific areas in Delaware, New Jersey, Pennsylvania and Virginia. DEC has established a Protective Zone encompassing 20 counties located near the Pennsylvania and New Jersey borders; in the Hudson Valley and Catskills, these include Broome, Delaware, Dutchess, Greene, Orange, Putnam, Rockland, Sullivan, Ulster and Westchester.

Research into potential biological controls is underway as well. The June 5 issue of Popular Science reported on some promising tests of a couple of fungi species by scientists at Cornell University: “The Batkoa fungus [Batkoa major] makes a particularly spectacular show of killing off the insect pest by acting as a sort of mind-controlling parasite. The researchers believe once Batkoa infects a spotted lanternfly, the fungus compels its victim to ascend up a tree or vine; then, fungal fibers sew it to its final resting place and spores burst out of the insect’s body to shower down onto any remaining lanternflies below.”

Sounds like a scene from Alien, but presumably these researchers already know to avoid the cane toad model. While we wait hopefully for their success, it’s up to us to keep our eyes peeled. To learn more, visit and