The spotted lanternfly is an invasive insect from Asia that feeds on plant sap. On Long Island, Cornell Cooperative Extension of Nassau County reported infestations as of November 17, 2021. In December 2024 the New York State Department of Agriculture and Markets said it had spread east in Suffolk, and News 12 reported in August 2025 that sightings were still moving east across both counties.
It feeds on more than 100 kinds of plants. Cornell names tree of heaven, grapes, black walnut, hops and maples as favorites, and says late-season adults also gather on willows and silver maples.
Each stage, and when you will see it
| Stage | When | What it looks like |
|---|---|---|
| Egg mass | Laid September to November, on surfaces until June | Rows of up to about 50 eggs under a putty-like coating, creamy white, then pinkish gray, then cracked tan like dried mud, about an inch long |
| Young nymph | May to July | About a quarter inch, black with white spots |
| Older nymph | July to September | Up to three quarters of an inch, red with white spots |
| Adult | July to December | About an inch long, pinkish tan wings with black spots, red hind wings with black spots, yellow belly with black bands |
The dates come from Cornell’s life cycle page and the NYS DEC life stages poster. DEC notes that lanternflies are often confused with other insects, so compare before you report.
Egg masses are the fall and winter job
Adults start laying eggs in September and keep going until the first hard freeze. The state says egg masses turn up on tree bark, stone, rusty metal, outdoor furniture, firewood and cars, often in tucked-away spots that are hard to see.
To destroy them, the Department of Agriculture and Markets says:
- Scrape the mass off with a scraper card, an old credit card, or anything hard, flat and tapered.
- Scrape it straight into a resealable bag with rubbing alcohol or hand sanitizer in it.
- Seal the bag and throw it away, so the eggs cannot hatch.
Cornell is honest about the limits: scraping the masses you can reach will not get them all, but it does cut down how many hatch in the spring. Check the undersides of patio furniture, the grill, the shed and the trailer before they get covered for the winter.
Will it hurt the trees in my yard?
Probably not in a lasting way. Cornell’s IPM program says spotted lanternflies “rarely cause damage to landscape trees” and that treatment is not necessary for the tree’s health. The feeding can stress plants, and the sticky honeydew they leave behind grows a black sooty mold on leaves, decks and cars below. News 12 points to that black mold as a sign they are around.
The ones who lose real money are grape growers. Cornell says unmanaged populations can drain grapevines, and the state estimates lanternfly could cost New York at least $300 million a year if it is not contained, mostly in grapes and wine.
If a tree in your yard is actually declining, lanternfly is unlikely to be the whole story. That is a question for an ISA Certified Arborist.
Traps, sprays and who should apply them
Traps. Cornell says traps work best set out by early May, when nymphs hatch and climb. Sticky bands catch birds, bats and helpful insects unless they have a barrier over them, and Cornell says to check them at least once a week. If a bird or bat gets stuck, do not try to free it yourself; take the band to a wildlife rehabilitation center. Circle traps use screening to funnel climbing lanternflies into a container at the top instead.
Insecticides. Cornell says systemic insecticides go in by bark spray, trunk injection or root drench, and that some people hire a certified pesticide applicator to do it. Use only products labeled for spotted lanternfly. Cornell Cooperative Extension of Westchester County warns against home remedies like kitchen vinegar.
Tree of heaven
Tree of heaven is itself an invasive tree, and it is the lanternfly’s favorite host. Cornell says older nymphs and adults prefer it, and that females lay more eggs sooner when they can feed on it.
Even so, Cornell is not recommending removing tree of heaven as a way to control lanternfly. The trees help track small populations, and a tree of heaven cut down without treating the stump can send up a whole grove of sprouts. If one is coming out anyway, Cornell says a registered systemic herbicide should go on the stump to stop regrowth. Cornell Cooperative Extension of St. Lawrence County describes two ways crews do this: the cut stump method, and hack-and-squirt, where the herbicide goes into cuts in the bark, with chemical treatment working best in late winter, early spring and summer.
Ask any tree removal company you call how they will treat the stump, and get it in the quote.
Report it, and don’t move it
In December 2024 the state was still asking for reports. Take a photo, then report it at agriculture.ny.gov/reportslf or email the photo and the location to spottedlanternfly@agriculture.ny.gov. After that, the state says to kill any others you find.
People spread lanternflies farther than they can fly, mostly by moving things with egg masses on them. Before you take firewood, a camper, outdoor furniture or a car out of an infested area, check it and scrape off anything you find.