Thank you for your commitment to slowing the spread of Spotted Lanternfly (SLF). Below are recommendations for management of infestations, as well as how to prevent the spread beyond Allegheny County as agreed upon by local organizations in the Western PA SLF Roundtable. A comprehensive SLF Management Guide from Penn State Extension can be found here. Below are major points that may be of interest: 

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Impact: 

• The most important thing to note is that, while SLF are annoying and have the potential to stress certain tree species in our region, they are NOT harmful to human health. SLF do NOT sting or bite.  

• SLF do produce a sweet secretion called honeydew as they feed on trees, which may attract other insect species such as bees or wasps. Honeydew may also lead to the growth of sooty mold, a plant pathogen that may further stress the tree species that SLF feed on. Before taking action, assess the risk that SLF possess to your landscape or agricultural operation.  

• The economic impact of SLF is limited primarily to grape vineyards, and possibly fruit orchards. Agricultural industry professionals are working with technical assistance providers to manage their land responsibly using integrated pest management strategies as they would for any other crop pest. 

Habitat: 

• Tree of Heaven: SLF prefer this as their feeding and egg laying habitat. Tree of Heaven (TOH) is an invasive weed and should be removed and replaced to prevent SLF population growth. 

• Other plant species that are often targeted by SLF include rose, grapes, black walnut trees, river birch trees, willow trees, sumac, red and silver maple, and fruit trees.  

  

Management: 

• SQUISH: While this may feel futile, each individual SLF that is killed can prevent up to 100 offspring from hatching in the following lifecycle. Squishing DOES make a big difference! Approaching from head on makes stomping more successful as SLF take off and fly in a forward direction. If approaching from behind, SLF can more easily escape your foot or fly swatter. 

• CIRCLE TRAP: Circle traps around infested trees can effectively capture SLF. You can make your own circle traps using household items using these directions, or purchase from a pest management supplier such as Great Lakes IPM. Do NOT use sticky bands!  

• REMOVE HABITAT: If you remove SLF preferred food and egg laying habitat, the population in the immediate area will decline. Identifying and removing tree of heaven plants from your property and surrounding areas is an extremely effective way of reducing SLF numbers. However, while Tree of Heaven (TOH) is also an invasive species, it does contribute to our urban canopy and may provide the same benefits that all trees do including but not limited to filtering pollution from air, storm water capture, reducing urban island heat effect, and more. If you remove TOH from your property, we recommend replacing with a native tree or shrub species. You can also reach out to a landscape or treecare professional to remove TOH from your landscape.

• INSPECT: SLF travel primarily as a result of human activity. They hitch rides on cars, bikes, trains, trucks, and more. Inspect your vehicle for nymphs, adults, and egg masses before traveling, especially if you have spent time in an infested area. Allegheny County has been designated as a quarantine zone for SLF, meaning that any businesses that travel or transport goods within or across boundaries of the county must obtain an SLF permit to reduce spread by human activity. Learn if your place of business should get a permit here!

• SQUISH EGG MASS: Egg masses can contain up to 50 SLF eggs. Adult SLF lay egg masses on many different surfaces. Identifying and squishing/ popping egg masses between September and June will prevent population increases on your property. You can also scrape egg masses into alcohol solution.

• VACUUM: You can utilize a handheld vacuum or shopvac to suck up SLF in nymph or adult stage. Empty vacuum into an alcohol solution to kill after sucking up.

• REPORT: PA Dept of Ag is tracking the movement of SLF across the state. If you observe SLF in a new location, please report your sighting by calling 1-888-4BAD-FLY (1-888-422-3359) or online.

• TREE CARE: While SLF can stress tree species, there are very few instances of SLF being solely responsible for tree death. Instead of spending resources on SLF extermination, it is encouraged that community members should instead spend time and resources on tree care, such as watering, mulching, pruning, etc., to increase tree resiliency in the face of stressors such as SLF. If your tree is healthy and strong, it will withstand pressure from SLF.

 

Avoid: 

• STICKY BANDS: Sticky bands, often placed around tree trunks, are more likely to attract and kill beneficial insects such as butterflies and other pollinators, as well as song birds, bats, birds of prey and more. If they must be used, sticky traps should only be used in combination with a mesh covering to prevent bycatch and must be checked daily to ensure other species are not being captured.  

• CONTACT INSECTICIDE: If an infestation is determined to need control, a broad spectrum contact pesticide may be used to kill SLF. A contact insecticide must be sprayed directly onto the insect. Natural insecticides that are less toxic such as insecticidal soaps or neem oil may be effective. However, please note that any broad spectrum insecticide will kill any and all insects it comes into contact with, including our beneficial insects and essential pollinators. Use these products as a last resort and be aware that NO insecticide product is specific to SLF; any application of an insecticide has the potential to kill non-target insects. Please note, foliar spray insecticides will NOT be effective to kill SLF as these insects do not feed on plant leaves. Pesticides should only be applied by trained professionals, and should be applied according to label instructions.

• SYSTEMIC INSECTICIDE: As a last resort, a systemic insecticide can be applied to habitat trees. Because SLF feed on the vascular tissue of plants using their straw-like mouth, systemic insecticides are effective in killing SLF. Please note, systemic insecticides should only be applied when a tree is NOT flowering to avoid killing essential pollinators and beneficial insects. Pesticides should only be applied by trained professionals, and should be applied according to label instructions.

  

The Western PA SLF Roundtable is comprised of the following organizations: 

• Allegheny County Conservation District 

• PSU Extension 

• Allegheny County Parks 

• Tree Pittsburgh 

• Western PA Conservancy 

• PA Master Naturalists 

• Upstream Pittsburgh 

• Phipps Conservatory 

• Pittsburgh Botanical Garden 

• Audubon Society of Western PA 

• Carnegie Museum of Natural History 

• Pittsburgh Parks Conservancy 

• Allegheny Land Trust 

 

Thank you again for your interest in reducing the SLF infestation here in Allegheny County! Your efforts are essential in preserving, protecting, and restoring our natural resources. Please do not hesitate to reach out with additional questions or concerns.