Spotted Lantern Fly Incoming!

Spring has arrived in Pennsylvania, bringing with it warming temperatures, budding plants, and, unfortunately, the return of the Spotted Lanternfly (Lycorma delicatula), also known as the SLF.

If you are unfamiliar with the SLF you can check out the USDA quick facts sheet. This hungry pest threatens not only our state's agriculture industry but also our backyard investments. Let’s meet the culprit.

What Is The Spotted Lanternfly?

The Spotted Lanternfly is an invasive pest indigenous to parts of China and Vietnam. It was discovered in PA in 2014 and is currently found in 51 counties across the state. At all stages of development, SLFs feed using piercing-sucking mouthparts, bypassing a plant’s protective layers to drain its sap, often consuming more than it can process and secreting large amounts of honeydew. (A sticky byproduct that will attract other bugs and pathogens)

What Do They Damage?

Pretty much anything you want to grow… Not exactly, but it feels that way with a pest that feeds on over 70 different plant species. While the full list is extensive, let's focus on common backyard plants and how to protect them. 

Hardwood Trees (Maple, Walnut, Oak, etc)

Spotted Lanternflies prefer to feed on hardwoods, particularly in late summer and fall, as adults. While healthy trees can generally withstand some feeding, repeated infestations weaken them over time. Here’s what you can do:

• Scrape & Destroy Egg Masses: From late fall to early spring, look for grayish-brown, putty-like egg masses on tree trunks and outdoor surfaces. Use a card or scraper to remove them, then crush or place in rubbing alcohol.

• Use Circle Traps Instead of Sticky Tape: Sticky bands can catch beneficial insects and even birds. Instead, opt for mesh-covered circle traps, which funnel SLFs into a collection bag while keeping wildlife safe. Penn State has a DIY video on circle traps.

• Consider Tree Banding in Heavy Infestations: If your area has many SLFs, wrapping tree trunks with a protective band (with a guard to prevent harming non-target species) helps reduce the number of nymphs on your trees.

Fruit Trees (Apple, Cherry, Peach, etc)

SLFs love fruit trees, which can suffer from stress due to excessive feeding. Protect them by:

• Regularly Check for Eggs and Nymphs: Examine tree trunks, branches, and nearby structures for egg masses. Destroy them before they hatch in spring (right now!)

• Applying Horticultural Oil in Early Spring: A dormant oil spray helps suffocate eggs before they hatch. Apply before the buds open.

• Using Netting to Block SLFs: If you have young trees or small orchards, using fine netting can help prevent SLFs from landing and feeding.

  

  
  

Vines/Ornamentals (Grape, Rose, Hops, etc)

Grapevines are one of the SLF’s favorite food sources, making this a major issue for both homeowners and vineyards across Pennsylvania.

• Physically Remove Nymphs & Adults: If you see clusters of nymphs, knocking them into a container of soapy water is an effective, non-toxic way to reduce their numbers.

• Apply Neem Oil/Insecticidal Soap: These organic options help manage small infestations without harming beneficial insects.

What Else Can I Do?

SLFs are not just backyard pests; they are a community-wide issue. Here are ways to be proactive:

• Report Sightings: When you spot SLFs in your area, you can report them to the state's agriculture department or use the SLFs reporting tool from Penn State Extension.

• Avoid moving SLFs: Check your car, firewood, and equipment before traveling.

• Encourage Natural Predators: Some insect predators, such as soldier bugs, praying mantis, and certain spiders, have been observed feeding on SLF making it critical to support biodiversity in your landscape.