Get the answers to the most frequently asked questions about spotted lanternfly, including their damage to plants, how to manage them on your property, and what you can do to help!
What is a Spotted Lanternfly? Where did it come from?
The spotted lanternfly is an invasive planthopper (a type of insect) in the U.S., first found in Berks County, PA in 2014. It is native to certain parts of Southeast Asia.
Are they a threat here in the U.S.?
Spotted Lanternflies feed on the sap of woody plants and trees and when there are large populations of them, they can cause significant damage to them. They feed on over 70+ plants, including important forestry and agricultural crops. The most damage to-date has been observed in vineyards, ornamental nurseries, and people’s backyards.
Are Spotted Lanternflies dangerous to pets?
Spotted lanternflies do not bite or sting humans or pets. No known toxins have been found in spotted lanternfly to-date. Pets are naturally curious and often ingest things they shouldn’t (especially when unsupervised), meaning there’s a possibility your pet will try to taste one.
The safest course of action is to keep pets away from living or dead SLF. If the pet does ingest anything outside their normal diet, or is showing signs of injury or illness, consult with a veterinarian right away.
Do spotted lanternflies kill trees and plants?
To-date, we have only seen spotted lanternfly kill sapling trees, sumac, grapevines, and tree-of-heaven. Healthy and established ornamental trees have not been recorded to have died from Spotted Lanternfly, though canopy dieback and plant health decline has been observed, particularly on some of spotted lanternflies favorite hosts including black walnut and maple.
Additionally, sooty mold has been recorded to kill ground cover plants, especially directly below large populations of spotted lanternfly in trees. This is a continued area of research.
Should I treat the trees in my yard?
There is no catch-all answer to this question, though it is frequently asked. It depends on many factors including what type of tree you have, how healthy it is, and the level of infestation you have.
Penn State University has developed guides to help you through this decision. For more information, visit: Deciding If and When to Treat for Spotted Lanternfly on Ornamentals.
Why are there so many Spotted Lanternflies on my building?
In the late summer & fall, you may see adult spotted lanternfly on the side of your building, telephone poles, or other structures. While we are still working to research their behavior, this is most likely driven by spotted lanternfly being attracted to tall objects either to have a meal or use as a launching post.
Additionally, they may be attracted to the heat of a building. The Spotted Lanternfly is not a structural pest & we generally do not recommend treating buildings for this insect. Without a food source, they will die.
Why isn’t this insect a problem in Asia?
Locations where the Spotted Lanternfly is found to be native also are host to an assortment of natural predators that keep its populations at steady levels, so it is not considered a pest at the same level it is here in the United States. Here, there are very few predators of the Spotted Lanternfly, in addition to a good number of suitable plant hosts, making population levels potentially extremely problematic (due to the amount of destruction they leave).
Do I need to actually scrape egg masses into a container with rubbing alcohol, or can I just scrape them on to the ground?
Egg masses need to be permanently submerged in rubbing alcohol to kill them. Eggs that have been scraped on to the ground can still hatch, so it is important to follow all recommended steps of egg removal!
How can I properly identify a Spotted Lanternfly if I see one?
Spotted lanternflies go through five stages of growth after hatching from eggs. The first four stages are called nymphs, which are incapable of flight. The young nymphs are black with bright white spots and are roughly the size of a pencil eraser. The next stages of growth are similar, but the nymphs become larger.
The fourth stage of spotted lanternflies, prior to adulthood, is vibrantly red with distinct patches of black and equally distinct bright white spots. The adult spotted lanternfly is about 1″ long. Adults have grey wings with black spots.
When the spotted lanternfly opens its wings, it reveals a bright red underwing. Spotted lanternflies live through the winter only as eggs. Adults lay eggs in masses in the late fall on trees, under bark, posts, lawn furniture, cars, trailers, outdoor grills, and on many other surfaces.
I think I killed/caught a Spotted Lanternfly… What do I do with it?
If you find a spotted lanternfly or a suspicious looking egg mass in a location where it is not known to exist, you should try to collect it and put it into a container filled with alcohol (rubbing alcohol, hand sanitizer, etc.) to kill and preserve it, or at least take a good picture of it.
Report your sighting online to the Spotted Lanternfly Project Reporting Center.
If you find any life stage of spotted lanternfly in a municipality where it is already known to exist, you should try to destroy it.
Do Spotted Lanternflies infest Christmas trees?
Real pine trees (as opposed to fake Christmas trees) are part of an outdoor ecosystem, and thus there is always a chance that any insect may be brought indoors with it. Although it is unlikely Spotted Lanternfly eggs will be on Christmas (or pine) trees, if they were to hatch indoors the nymphs pose no threat to humans or animals, and will quickly dehydrate and die as there is no food sources available to them.
Most good Christmas tree farms follow integrated pest management practices to minimize such threats. If consumers are concerned, they are encouraged to inspect the tree prior to purchase. Spotted lanternfly egg masses are visible on the bark if present and can be easily removed.
Can I prevent spotted lanternflies from getting on my property?
The simple answer? NO… Spotted Lanternflies can not be prevented from coming on to your property, particularly as adults when they become more mobile. However, their presence alone does not indicate that you will have plant decline on your property. In some cases, the insects may just be attracted to your building.
They do not cause structural damage and may just be seeking this out for warmth, height, or other unknown reasons. The best thing any property owner can do is become informed about spotted lanternflies. Additionally, feel free to reference our online Spotted Lanternfly Management Guide for what management tactics to use, on which trees, and when.
How does the Spotted Lanternfly feed? What is honeydew?
The Spotted Lanternfly feeds through the bark using a piercing-sucking mouthpart tapped into the plant like a straw. When it feeds, it excretes honeydew, or sugary water on and around its feeding site. This sugary substance encourages the growth of black sooty mold, which is not harmful to humans, but can damage plants and make outside recreation areas unusable.
Does the spotted lanternfly bite or sting?
No, the Spotted Lanternfly does not bite or sting, and is considered to be harmless to both humans and pets. In fact, Spotted Lanternflies are actually very closely related to Cicadas (which are also harmless to humans and pets, but bad news for trees and woody plants)!
Does the spotted lanternfly have natural enemies here in the U.S.?
Yes. Several common insects such as spiders and praying mantises are known to attack and feast on Spotted Lanternflies. Additionally, several species of birds have also been found to prey on Spotted Lanternflies as well. More research is currently being carried out, but these predators alone are unlikely to reduce or eliminate spotted lanternfly from an area.
How are they spreading so fast?
Since Spotted Lanternflies lay eggs on almost any surface, including vehicles like rail cars and trailers, as well as outdoor equipment and patio furniture, these pests are easily spread by people. Before you travel within or out of the quarantine zone, check your belongings, yourself, and your vehicle for Spotted Lanternfly!
How can I help?
Report your sightings of spotted lanternfly using our online reporting tool. Make sure you are not moving any life stage of spotted lanternfly when traveling within or out of the quarantine zones. And finally, tell your friends, family, and neighbors! The more you can spread awareness about the insect, the better chance we have against fighting it!