Spotted Lanternfly

Four photos showing the various life stages of the Spotted Lanternfly
Top left corner: 1st stage of Spotted Lanternfly life cycle
Top right corner: As the Lanternfly matures, it becomes red with black and white patches
Bottom row: Adult Spotted Lanternfly

Frequently Asked Questions

What is the Spotted Lanternfly and where did it come from?

The Spotted Lanternfly (Lycorma delicatula) is a member of the planthopper family and an invasive insect new to the United States. SLF are native to Southeast Asia, but they have been introduced to other areas, including Korea, where they are a major pest to agriculture. SLF are reproducing quickly in southeastern Pennsylvania and have the potential to become a major threat to our agriculture and forestry industries.

How do I identify a Spotted Lanternfly?
SLF live through the winter only as eggs. Eggs are laid in masses on trees, under bark, on rusty metal, on plastic yard objects, on cars and trailers, on outdoor grills, and on many other surfaces. Newly laid egg masses have a grey mud-like covering which can take on a dry cracked appearance over time. Old egg masses appear as rows of 30-50 brownish seed-like deposits in 4-7 columns on the trunk, roughly an inch long.

In late April and early May, young nymphs hatch. They are wingless and are black with bright white spots.

As the nymphs mature they become vibrantly red with distinct patches of black and equally distinct bright white spots.

Adults appear in July. The adult is a winged, flying leaf-hopper about 1 to 1 and ¼ inch long with grey wings with dark black spots. When the SLF opens its wings, you’ll see a bright red underwing with black wingtips. They are poor flyers but strong jumpers.


Do Spotted Lanternflies kill trees and plants?
SLF are new to North America, and there is much that we don’t know. As of now, we have no knowledge that SLF kill trees and plants. In Korea, however, SLF have had a major destructive impact on grapes, apples, pines, and many other plants. Because of the potential damage SLF could do to agriculture and forestry products, they are considered a threat to the economic well-being of our state and its citizens.


Are Spotted Lanternflies dangerous to children and pets?
SLF are not known to bite, sting, or attack people, pets, or livestock. It is not known if SLF are poisonous when ingested by humans or animals.


Can I prevent Spotted Lanternflies from getting on my property?

The best thing any property owner can do is to stay informed about SLF. Learn how to identify egg casings as well as all the life stages and monitor your property for signs of infestation. Remove or treat any Ailanthus trees (also called Tree of Heaven and considered a key tree host for SLF). In winter, scrape egg casings into a bag, seal it, and dispose of it in the trash. In the summer, place sticky bands around target trees; however, these bands should be carefully selected, covered with wire fencing, and monitored to prevent other wildlife like birds from becoming trapped. Finally, encourage natural predators by avoiding spraying pesticides. Information on treatment options can be found on http://extension.psu.edu/pests/spotted-lanternfly


What is the park doing about Spotted Lanternflies?
  • Selecting Ailanthus trees for treatment with a systemic pesticide and removing untreated trees. Since Ailanthus is a non-native tree, few if any native insects feed on the tree and unintended kill will be minimized
  • Monitoring for damage
  • Removing egg cases, setting traps, and banding the most important trees with an insect-targeting sticky band
  • Removing egg cases along trails with volunteer assistance.

Can I conduct research on Spotted Lanternflies in the park?
Yes, we encourage scientific research in the parks but you must apply for a research permit. Permit applications can be submitted at https://irma.nps.gov or by contacting Amy Ruhe, Natural Resource Manager, at e-mail us or 610-783-1036.

What’s Next?
There is much we don’t know but observations are promising:
  • In Berks County, where the infestation began, few SLF have been seen in 2019
  • Praying mantises and some bird species have been observed feeding on SLF. Preserving these natural predators is an excellent reason to avoid spraying your property.
  • There is a native fungus whose spores appear to attach the SLF

Where can I get more information?
Check out the following websites for additional information and current information on management efforts:

https://www.agriculture.pa.gov/
http://extension.psu.edu/pests/spotted-lanternfly

For information on further questions in regard to the National Park Service and Spotted Lanternflies please email Amy Ruhe, Natural Resource Manager at e-mail us or 610-783-1036

Last updated: August 29, 2019

Contact the Park

Mailing Address:

1400 North Outer Line Drive
King of Prussia, PA 19406

Phone:

(610) 783-1000

Contact Us