The spotted lanternfly has spread across nearly all of Pennsylvania since it was first detected in Berks County in 2014. Today, 56 of the state’s 67 counties are under a state-imposed quarantine, and the insect causes an estimated $50 million in annual damage within the quarantine zone alone. If you live in Pennsylvania, here’s what you need to know about identifying, reporting, and managing this invasive pest.
How to Identify Each Life Stage
The spotted lanternfly goes through one generation per year. Adults die in winter, but their eggs survive the cold and hatch the following spring. Knowing what to look for in each stage helps you act at the right time.
Egg masses (October through May): Females lay flat, grayish-brown egg masses about one inch long on nearly any hard surface: tree bark, stone walls, patio furniture, vehicle undercarriages, even grills and playground equipment. Fresh egg masses are covered in a white, putty-like coating. Over the winter months, that coating cracks and weathers to look like dried mud. Once the covering wears off, you can see individual seed-shaped eggs underneath.
Early nymphs (May through July): Newly hatched nymphs are just a few millimeters long and grow to about a quarter inch. They’re black with bright white spots and are surprisingly strong jumpers. They’ll leap away when disturbed.
Late nymphs (July through September): In their final nymph stage, they’re about half an inch long and shift to a striking bright red body with black stripes and white spots. They remain strong jumpers.
Adults (July through December): Adults are roughly one inch long with grayish forewings dotted in black spots. When they open their wings, they reveal bright red hindwings with black patches. Females tend to be slightly larger than males.
Which Counties Are Under Quarantine
Pennsylvania’s quarantine now covers 56 counties, stretching well beyond the original southeastern epicenter. The list includes Adams, Allegheny, Armstrong, Beaver, Bedford, Berks, Blair, Bradford, Bucks, Butler, Cambria, Cameron, Carbon, Centre, Chester, Clearfield, Clinton, Columbia, Cumberland, Dauphin, Delaware, Fayette, Franklin, Fulton, Greene, Huntingdon, Indiana, Juniata, Lackawanna, Lancaster, Lawrence, Lebanon, Lehigh, Luzerne, Lycoming, Mercer, Mifflin, Monroe, Montgomery, Montour, Northampton, Northumberland, Perry, Philadelphia, Pike, Schuylkill, Snyder, Somerset, Sullivan, Union, Venango, Washington, Wayne, Westmoreland, Wyoming, and York.
If you live or work in a quarantined county, you’re expected to inspect vehicles, outdoor equipment, and shipments before moving them out of the zone. Businesses that transport goods through quarantined areas need a permit from the Pennsylvania Department of Agriculture. The goal is to prevent hitchhiking egg masses and nymphs from spreading the insect to new regions.
Economic Damage to Pennsylvania
The spotted lanternfly feeds on more than 70 plant species, but its impact hits hardest on grapes, fruit orchards, hardwood timber, and ornamental nurseries. Within the current quarantine zone, annual damage is estimated at $50.1 million with a loss of 484 jobs. A worst-case scenario in that same area pushes the figure to $92.8 million and 927 lost jobs.
The broader picture is more alarming. A Penn State economics study found that if the lanternfly spreads unchecked throughout the entire state, it could drain Pennsylvania’s economy of up to $554 million annually and eliminate nearly 5,000 jobs. Even a more conservative statewide projection lands at $324 million per year and roughly 2,800 jobs lost. The grape and wine industry is particularly vulnerable, since the insect feeds heavily on grapevines and can weaken or kill them over successive seasons.
How to Destroy Egg Masses
Scraping egg masses is one of the most effective things individual Pennsylvanians can do. Eggs are viable from about October through July, so the best window for finding and destroying them runs from late fall through early spring, before nymphs hatch in May.
Use a plastic card, putty knife, or similar flat edge. Press down firmly as you scrape. You should hear the eggs pop and see liquid come out. That popping confirms you’ve killed the developing nymphs inside. If you scrape too lightly and the eggs remain intact, they’re still viable. After scraping, collect the eggs in a plastic bag filled with hand sanitizer or rubbing alcohol. Make sure all the eggs contact the liquid, seal the bag, double-bag it, and throw it in the trash. Don’t climb ladders to reach egg masses that are high up; focus on what you can safely reach.
Check tree trunks, fence posts, stone surfaces, outdoor furniture, trailers, and firewood stacks. Egg masses blend into rough bark surprisingly well, so look carefully.
Managing Nymphs and Adults
Once nymphs hatch, trapping and targeted insecticides become your main tools. Penn State Extension recommends a funnel-style “circle trap” that wraps around tree trunks and funnels lanternflies into a collection container as they climb upward. These traps are selective and effective.
Sticky bands (glue traps wrapped around trees) are another option, but they come with a serious tradeoff: they catch everything, including pollinators, butterflies, birds, and small mammals like squirrels. If you use sticky bands at all, you need to install a wildlife barrier (typically a cage of hardware cloth or chicken wire) around them. Penn State does not recommend unprotected sticky bands.
For direct treatment, nymphs and adults are relatively easy to kill with low-toxicity insecticides like insecticidal soaps and horticultural oils. These are available at most garden centers. Choose the least toxic option that’s registered for your intended use, and always follow the label directions. Spraying works best as a spot treatment when you see lanternflies congregating on a tree or vine, not as a broad preventive measure.
Natural Predators Gaining Ground
Pennsylvania researchers have been investigating which native species prey on spotted lanternflies, and the results are encouraging. Penn State scientists tested 10 generalist predators in controlled settings, placing them in enclosures with either 25 nymphs or 10 adults for up to a week. Spined soldier bugs, a predatory stink bug native to North America, were the standout performers. A group of eight spined soldier bugs consistently consumed every lanternfly in the enclosure, regardless of life stage, within three to four days. Carolina mantises and Chinese mantises were also effective predators.
A citizen science effort from 2020 to 2022 collected nearly 2,000 public reports of birds and insects feeding on spotted lanternflies, giving researchers a broader picture of natural predation in the wild. One important finding: predators consumed lanternflies regardless of whether the insects had been feeding on tree of heaven (their preferred host plant) or other species, meaning the lanternfly’s diet doesn’t seem to make it unpalatable.
These predators won’t eliminate the spotted lanternfly on their own, but they represent one layer of a long-term management strategy. Biological control research, including work on parasitoid wasps and fungal pathogens, continues across the state.
What You Can Do Right Now
If you’re in Pennsylvania, your most impactful actions depend on the season. From October through April, check your property for egg masses and destroy them. From May through September, set circle traps on heavily infested trees and stomp or squish nymphs and adults when you see them. Year-round, inspect your car, camping gear, firewood, and anything stored outdoors before moving it to a new location.
Reporting new sightings still matters, especially in counties not yet under quarantine. You can report through the Pennsylvania Department of Agriculture’s online tool or by calling their hotline. Include a photo and your location. Even in heavily infested areas, tracking population density helps the state allocate resources and measure whether management efforts are working.