Spotted Lanternflies and What the World Is Doing About Them

Spotted lanternflies are one of those insects that somehow went from something I had never heard of to something I now see every summer around Philly. If you live anywhere around here, you probably know exactly what I mean because they’re on sidewalks, trees, patios, vineyards, parking lots, and occasionally flying directly toward your face with absolutely horrible navigation skills. If one more of those mo-fo’s bounce off my head I’m going to lose it.

The weird part is that they’re actually kind of beautiful bugs.

Adult spotted lanternflies have pale grayish forewings covered in black spots, but when those wings open, there’s this incredibly bright flash of red underneath along with black, white, and yellow. They look far more exotic than most of the insects hopping around Pennsylvania because, well…they are.

Spotted lanternflies (Lycorma delicatula) are native to parts of Asia, and the first confirmed U.S. population was found in Berks County, Pennsylvania, all the way back in 2014. The exact journey here is difficult to reconstruct years later, although investigators found a large population around a commercial property associated with imported stone, and a federal technical working group concluded that egg masses probably arrived on stone shipments from China. These little suckers are incredibly talented hitchhikers, laying eggs on stone, vehicles, pallets, patio furniture, trailers, equipment, and plenty of other hard surfaces that we tends to move around.

From that first population in southeastern Pennsylvania, spotted lanternflies spread through the Mid-Atlantic and continued into a growing portion of the eastern United States. Their ability to hitch rides matters far more for long-distance movement than their flying ability, which is why agriculture departments spend so much time asking people to inspect cars, trailers, outdoor equipment, firewood, and anything else traveling out of infested areas.

They leave people and pets alone because those piercing mouthparts are designed for feeding on plants, which is where the actual problem begins.

The Damage Spotted Lanternflies Cause

Spotted lanternflies basically drink for a living (ha, relatable!). They insert piercing-sucking mouthparts into plant tissue and feed on phloem sap, and while one little lanternfly hanging out on a giant healthy tree is fairly uneventful, thousands feeding together can create a very different situation. I mean, these are tiny little vampire bugs and plants are their favorite meal.

They feed on a huge variety of plants including grapevines, maples, black walnut, willow, tree-of-heaven, hops, ornamentals, and plenty of other species, although grapevines have emerged as one of the plants scientists are particularly concerned about. Heavy populations on grapevines can reduce photosynthesis and sap flow, lower carbohydrate and nitrogen reserves in the roots, affect sugar accumulation in the grapes, reduce future yields and, under severe pressure, contribute to vine death. As a sommelier living in Pennsylvania, this is obviously the part where I start taking the bug situation a little personally.

The story with trees has become considerably more reassuring as scientists have accumulated years of observations. Early in the invasion there was understandable concern about widespread tree mortality, while current research paints a more specific picture: spotted lanternfly feeding can stress trees and contribute to branch dieback, especially when populations are huge or the plant already has other problems, while direct deaths have mostly been documented in grapevines, tree-of-heaven, and black walnut saplings. Your mature maple with three lanternflies sitting on it is dealing with a very different situation than a grapevine covered in hundreds of adults.

Then we have the honeydew, which is probably the part homeowners notice most.

Because these insects consume enormous amounts of sap to get the nutrients they need, they also excrete enormous amounts of sugary liquid called honeydew. It can rain down beneath heavily infested trees onto leaves, decks, cars, patio furniture, sidewalks, and basically anything unlucky enough to be sitting underneath them. The sugar attracts ants, bees, wasps, and other insects, and fungi called sooty mold can grow across surfaces coated in it, sometimes creating those bizarre blackened areas you see beneath a heavily infested tree.

A Penn State economic analysis estimated that an uncontrolled spotted lanternfly infestation could cost Pennsylvania about $324 million per year and more than 2,800 jobs, with industries including grapes, nursery plants, timber, and related businesses exposed to some of the risk.

What Eats Spotted Lanternflies?

This might be my favorite part of the entire lanternfly story because nature has apparently been figuring out what to do with them while we’ve been outside stomping them.

Spotted lanternflies arrived in North America without the same predator relationships they evolved alongside in Asia, although plenty of generalist predators here have figured out that this new bug is edible. Researchers collecting community-science observations received more than 1,200 reports of spotted lanternfly predation, with birds accounting for hundreds of those observations and arthropods accounting for even more. Cardinals, catbirds, blue jays, tufted titmice, and chickens were among the commonly reported birds, while praying mantises, spiders, yellow jackets, wheel bugs, and ants also showed up repeatedly as predators.

I can personally add a very enthusiastic vote for the catbirds because they helped massively in my garden this year. I started noticing them working their way around the plants and eating lanternflies, and suddenly I became extremely supportive of whatever catbird convention had apparently moved into my yard.

What You Can Do About Spotted Lanternflies at Home

Living in an area where spotted lanternflies are already established can make the whole thing feel slightly ridiculous because you can squash five of them and then look up to find another fifty sitting in the tree above you. There are still some useful things you can do around your house though, especially if you focus on preventing spread and targeting life stages when they’re easiest to reach.

Squash the ones you find. Pennsylvania still encourages residents to physically destroy spotted lanternflies, especially adults and nymphs you can easily reach. They normally have one good hop in them, so if you miss it the first time, the second time is typically the charm!

Look for egg masses during the colder months. A female lays egg masses containing roughly 30–50 eggs, usually under a grayish or brown covering that starts fairly smooth and eventually looks a little like dried or cracked mud. They show up on trees, rocks, outdoor furniture, decks, fences, equipment, vehicles, and all sorts of other surfaces, so winter is actually a great time to look around when the insects themselves have disappeared. When you find an accessible egg mass, Penn State recommends either thoroughly smashing the entire mass or scraping it into a container or bag containing rubbing alcohol or hand sanitizer. The important part is actually destroying the eggs because an egg mass scraped onto the ground can still hatch. Also, most egg masses on large trees are above a safe reachable height, so the goal is taking care of the ones you can reach from the ground rather than auditioning for an emergency-room visit with a ladder.

Please God, be thoughtful with insecticides too. Mix 1 quart of water with about 1 teaspoon of plain, unscented liquid dish soap. Put it in a spray bottle and spray the lanternfly itself thoroughly. The soap disrupts the insect’s outer protective layer and works best when it actually contacts the insect. Spray individual lanternflies or small clusters, avoid flowers where bees and butterflies are feeding, and avoid coating an entire tree or garden bed. Soap can injure leaves too, especially in hot sun, so test it on a couple of leaves first and apply in the cooler morning or evening. You can rinse the plant with plain water afterward if you’ve sprayed heavily.

I would skip the vinegar, salt, bleach, essential-oil, and rubbing-alcohol recipes you see online. They’re much more likely to damage plants, soil, pollinators, or other insects.

Meanwhile, I’m rooting for the catbirds in my garden. They seem to have figured out the assignment.

What the World Is Doing

While we’re outside scraping egg masses and squashing whatever lands on the patio, researchers are out there working on much bigger solutions, thankfully. Penn State, Cornell, Rutgers, USDA, and state agriculture departments have spent years tracking spotted lanternflies, studying how they move, testing traps, and looking for better ways to protect grapes and other vulnerable crops.

One of the most interesting areas is biological control. Scientists have been studying parasitoid wasps from the lanternfly’s native range, including Dryinus sinicus, which attacks nymphs. Before anything like that can be released here, researchers have to make sure it targets lanternflies closely enough to keep native insects safe too. That process takes time, but a predator that could quietly keep lanternfly populations lower year after year would obviously be a huge win.

Quarantines also play a big role because these bugs are incredible hitchhikers. Their egg masses can stick to vehicles, trailers, firewood, stone, patio furniture, equipment, and basically anything else that sits outside long enough. That’s why states focus so much on inspections and asking people to check what they’re moving before leaving an infested area.

A Much Bigger Invasive Species Problem

Spotted lanternflies are also a pretty perfect example of how easily living things travel with us now. We move plants, stone, wood, cars, equipment, food, and cargo across the world constantly, and occasionally something small manages to come along for the ride.

Once an invasive species reaches a place with plenty of food and a climate it likes, things can move very quickly. We’ve seen the same story with emerald ash borers, zebra mussels, lionfish, tree-of-heaven, and plenty of others.

Living in Pennsylvania just makes the spotted lanternfly version feel especially personal because I can literally watch it happening in my own backyard.

Somehow, They’re Still Pretty

I still think spotted lanternflies are beautiful insects, which is lame to say considering how annoying they’ve become. Their gray spotted wings look almost painted, and when they jump there’s that sudden flash of red underneath that makes them much prettier than I want them to be.

As a sommelier, though, the grapevine damage is where I start taking things personally.

What I find most interesting now is watching the ecosystem slowly adjust around them. Birds are eating them, native insects are hunting them, researchers are studying natural enemies, and growers are getting much better at figuring out what actually protects vineyards.

For now, I’ll keep destroying the egg masses I can reach, squashing the adults around my plants, checking anything I move out of the area, and enthusiastically supporting every catbird that decides to help me out.

If you want to put up one of those cool traps, try this one! It works surprisingly well, and no spraying required.

Sources

Johnson, A. E., Cornell, A., Hermann, S., Zhu, F., & Hoover, K. (2023). Using community science to identify predators of spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), in North America. Bulletin of Entomological Research, 113(5). https://doi.org/10.1017/S0007485323000317

Johnson, A. E., Cornell, A., Zhu, F., Shay, A. E., Davis, G., & Hoover, K. (2025). Sequestration of plant defenses by spotted lanternfly (Lycorma delicatula) and effects on avian predators. Journal of Chemical Ecology, 51, Article 102. https://doi.org/10.1007/s10886-025-01647-6

Krawczyk, G., Leach, H. L., Briggs, L., & Calvin, D. (2026, June 1). What should you do with spotted lanternfly egg masses? Penn State Extension. https://extension.psu.edu/what-should-you-do-with-spotted-lanternfly-egg-masses

Leach, H., Swackhamer, E., Korman, A., & Walsh, B. (2024, June 10). Spotted lanternfly management guide. Penn State Extension. https://extension.psu.edu/spotted-lanternfly-management-guide

Penn State Extension. (2026, June 15). Spotted lanternfly frequently asked questions. https://extension.psu.edu/spotted-lanternfly-frequently-asked-questions

Pennsylvania Department of Agriculture. (n.d.). Spotted lanternfly program information. Commonwealth of Pennsylvania. https://www.pa.gov/agencies/pda/plants-land-water/spotted-lanternfly/spotted-lanternfly-program-information

U.S. Department of Agriculture, Animal and Plant Health Inspection Service. (2025, August 26). Spotted lanternfly. https://www.aphis.usda.gov/plant-pests-diseases/slf