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Spotted Lanternfly Management Guide Supplement

Supplement for green industry professionals and natural resource managers on the spotted lanternfly and effective management strategies.

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Updated:

June 10, 2026

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Introduction

The spotted lanternfly (SLF), Lycorma delicatula, a sap-feeding planthopper, presents many challenges in different landscapes. In residential areas, it is primarily a nuisance pest. In other sites, infestation may result in a range of impacts from direct (e.g., damage to plants) to indirect (e.g., costs associated with quarantine compliance). Each specific managed landscape or natural area presents a unique set of considerations. Deciding if control is warranted, and subsequent selection and implementation of management practices, requires thoughtful decision-making based on scientific knowledge and available options.

This supplement compiles additional research-based information about SLF, which is intended to provide a deeper understanding of this insect to aid professionals whose duties are impacted by SLF or the legal requirements associated with it. This is not a literature review. Instead, relevant conclusions from selected scientific studies are summarized to help guide informed management decisions. This supplement highlights challenges for making management decisions based on current knowledge. It can also help guide research planning by highlighting gaps in knowledge needed to improve practical management options.

Individuals interested in learning more can access additional in-depth information through the "Stop SLF" website. This website includes an extensive list of peer-reviewed research publications, links to presentations, reports, and maps showing current SLF distribution.

Many SLF adults on a black walnut tree — Figure 1. Spotted lanternfly adults on a black walnut tree. Credit: Brian Walsh

Basic information about SLF can be found in The Spotted Lanternfly Management Guide (SLFMG). The SLFMG includes information about the insect's biology and a summary of management practices. We refer the reader to specific sections of the SLFMG throughout this supplement.

Feeding Damage and Impact (SLFMG, page 5)

SLF feeding stresses plants. On some plants, it can be devasting. Most plant hosts tolerate light or moderate SLF feeding pressure with no apparent effects. However, multiple years of heavy SLF feeding can weaken plants. Weakened plants are more vulnerable to additional stress from adverse conditions, such as improper planting and weather extremes as well as invasion by opportunistic pathogens and insects. Death believed to be directly linked to SLF has only been observed in three preferred hosts, specifically Ailanthus altissima (tree-of-heaven or TOH), grapevines, and black walnut saplings.

Many red and black SLF nymphs on a black walnut twig — Figure 2. Heavy SLF nymph feeding caused premature fall coloration and defoliation of a black walnut branch in late July. Credit: Emelie Swackhamer

What Else Do We Know?

In experiments, high SLF feeding pressure reduced leaf nutrient concentrations, tissue carbohydrate levels, and growth in some trees compared with uninfested controls.
Researchers have shown direct relationships between SLF abundance and mineral content in host plant foliage, including nitrogen, indicating that fertilization may increase SLF attraction.
Experiments to determine whether SLF can directly transmit specific plant pathogens under field conditions are ongoing. Results to date are inconclusive.
Localized tissue damage has been observed in several tree species following SLF feeding. In maples, specific cultivars may be more prone to this type of damage
As the SLF geographic range increases, we suspect there will be additional plants added to the host list, including additional preferred hosts. Anecdotal observations from landscape professionals suggest that less common ornamental plants, including Styrax japonicus (Japanese snowbell), Tetradium daniellii (Bee-bee tree, previously known as Evodia), Melia azedarach (chinaberry), and Lagerstroemia sp. (crape myrtles), are likely favored host plants of SLF.

Recommendations

Use good cultural practices to maintain plant health to compensate for any effects of SLF feeding.
Avoid overfertilization.
Use Integrated Pest Management (IPM) practices to reduce SLF on preferred host plants in the landscape, particularly during the adult life stage when the insects are large and feeding voraciously.

Research Needed

Develop IPM action thresholds by further quantifying the physiological effects of different levels of SLF feeding pressure for common hosts.
Determine how feeding stress may affect host susceptibility to other factors.
Conduct comparative investigations across the spectrum of plant hosts focused on the impact of SLF feeding relevant to SLF lifecycle and host preference timing in wild populations.
Investigate how host plant health and nutritional status (including fertilization impacts) affect SLF population development.
Evaluate the importance of localized feeding damage to phloem tissues and possible opportunistic infection at those sites.
Investigate SLF and possible disease transmission.

Nuisances Created by SLF (SLFMG, page 5)

SLF contributes to nuisance problems in the landscape. SLF excrement, known as "honeydew," is high in sugar due to SLF's sap-feeding diet. Honeydew attracts stinging insects that feed on it. Honeydew is also a substrate for sooty mold, which can stain plants, structures, or vehicles beneath trees infested with feeding SLF. On TOH, a preferred host, extensive SLF feeding can result in the development of a slime flux, a milky, pungent, fermenting froth containing yeasts and bacteria that builds up on the tree and under the bark. This condition can accelerate tree decline and inhibit translocation of systemic insecticides. In other trees without SLF infestations, a similar condition is sometimes referred to as "bacterial wetwood" or simply "wetwood."

Base of a Tree showing visible signs of honeydew and sooty mold. SLF adults are present. — Figure 3. Honeydew, sooty mold, and slime flux (white microbial growth) on a TOH infested with SLF adults. Credit: Emelie Swackhamer

Recommendations

Identify host plants where nuisance issues are problematic.
Manage SLF populations with recommended IPM practices if necessary to prevent honeydew and sooty mold production.
Remove dying or dead TOH as necessary for safety.

Research Needed

Investigate how feeding on SLF honeydew affects other insects including pollinators.
Evaluate the impact of sooty mold on understory plant growth and development.
Identify microbes that cause sooty mold and white froth and investigate their potential impacts.

SLF Quarantine and Permitting

To protect vulnerable plants and industries, it is important to avoid spreading SLF to new areas. Some affected states have enacted quarantine orders to try to prevent human- assisted spread of SLF. In Pennsylvania, all businesses and residents must comply with the Pennsylvania Department of Agriculture (PDA) SLF quarantine order and regulations. Specifically, an SLF Permit is required for businesses, agencies, and organizations that move regulated articles (such as products, vehicles, or other conveyances) within or out of the quarantine zone. The quarantine order requires that any items being moved from known infested areas be inspected and the SLF destroyed before shipment. These actions must be documented. Examples of businesses that need a permit can be found at PDA's SLF "Do I Need a Permit?".

The PDA offers best management practices fact sheets on their website to help several specific industries comply with the regulations.

Monitoring (SLFMG, page 7)

Monitoring SLF is challenging because SLF is very mobile. In infested areas, SLF population levels vary greatly from one location to another, and SLF continues to move into new areas. Monitoring is critical to inform management timing near high-risk areas (e.g., vineyards, nurseries, transportation corridors, etc.). In general, focus monitoring efforts on TOH and other host plants preferred by the life stage present.

Monitoring Methods that Work

Traps are most effective to monitor for nymphs, but they can be left in place for the adult stage. Visual counts are more effective to monitor for adults, but usefulness may be limited by the labor resources needed (see Mechanical Control: Traps).

Recommendation

Choose a monitoring method appropriate for your site, budget, and management needs.

Research Needed

Evaluate the sensitivity of different monitoring methods and situations.
Refine additional monitoring techniques, including environmental DNA capture and trained detection dogs.
Develop a field-tested lure that attracts SLF.

Seasonal Population Fluctuations (SLFMG, page 7)

Targeting Hosts in a Specific Area

SLF has been observed to feed on nearly all nonconifer plants but clearly has preferred hosts. Moreover, host selection is correlated with available hosts and lifecycle stage. In each area, SLF primarily feeds on the most preferred hosts, almost to the exclusion of other hosts. Selective feeding provides an opportunity to target hosts for treatment.

For example, visual surveys performed in fall 2020 (B. Walsh et al., unpublished) showed clear tree host preferences in a shopping center parking lot. The area surveyed covered 16.5 acres (0.15 km²) and included 222 deciduous trees representing 10 species, and 4,877 SLF were recorded. Most (97.8%) SLF were found on red maple (Acer rubrum), which represented only 31% of the total number of trees and only 24% of the total diameter at breast height of all deciduous trees in the area (Figures 5 and 6). If management is desired, this research indicates that treatment of all trees present is not necessary but should target red maple, the preferred host at this site.

Figure 4. SLF adults flying around apple trees in September. Credit: Erica Smyers

Recommendations

Before implementing any management plan, scout potential hosts to determine where SLF is primarily focused.
Host selection will vary in accordance with hosts and SLF lifecycle timing.
Do not treat all potential hosts with insecticides if SLF is not present on them.

Little is known about SLF dispersal ecology, and accurate population prediction is currently impossible. In a specific location, numbers of SLF often vary within the season. SLF can move significant distances, on the ground as nymphs or by flight as adults. Large flights of dispersing adults have been observed, usually beginning in September in Pennsylvania and continuing sporadically for several weeks. The maximum possible distance they can travel is unknown. Weather conditions may increase dispersal distances when adults move with rising air thermals.

During dispersal, adult lanternflies have been observed moving from outside locations to vineyards and plant production nurseries to feed, mate, and lay eggs. They have also been observed moving into Christmas tree farms in the fall, and, although they do not prefer to feed on conifers, this creates concern about the potential for egg masses to be transported on this crop. During dispersals, adults may also be attracted in high numbers to tall vertical objects like buildings or utility poles, which can cause concern for residents.

Pie chart showing SLF host species with red maple being the dominant host (98%) — Figure 5. SLF preferred maple in this study. Credit: Brian Walsh

Pie chart showing breakdown of SLF host species by DBH (Diameter at Breast Height) — Figure 6. Sum of tree diameter at breast height (DBH) in inches of total trees observed in a parking lot showing the abundance of red maple. Red maples represented 31% of the trees observed by count and only 24% of the sum of diameter inches (DBH) present. Credit: Brian Walsh

Recommendations

Scout for SLF throughout the season.
On some properties, it may be necessary to reduce nuisance issues associated with dispersing adults gathering on host trees or buildings, and it may be necessary to use insecticides. Insecticides should be chosen in accordance with the label site use allowances (e.g., ornamental plantings, nursery stock, building facades, inside warehouse distribution facilities, etc.). If the chosen insecticide provides little or no residual efficacy, applicators may have to repeat applications with higher frequency. If possible, form a management plan before adult dispersal based on which plants are present, the history of SLF behavior from previous years, and acceptable treatment options. Then, if SLF gather in large numbers in that area, you will be prepared to react.
Anyone who ships or moves items that were outside, such as plants, crops, construction equipment, etc., should monitor for dispersal behavior and watch for egg laying. If SLF appears, use recommended management methods to address and protect plants and products before shipping.

Research Needed

Identify triggers for dispersal behavior of the different life stages.
Identify oviposition site preferences.
Develop effective techniques for tracking dispersal.
Determine maximum natural dispersal distances for nymphs and adults.
Evaluate weather effects on dispersal capabilities to enhance predictive capabilities.
Develop methods for more accurate area-wide population size estimates.

Annual Population Fluctuations (SLFMG, page 7)

Populations of SLF can be high in newly invaded areas, but populations frequently decline after a few years. Unfortunately, after a season of low population numbers, it is not uncommon to see an increase the following year. Population density, host fitness, natural enemies, weather conditions, and control measures are likely the primary factors determining these fluctuations. Moreover, these factors can interact. For example, wet weather conditions may make naturally occurring fungi that can kill SLF more active, a late freeze may kill newly emerged nymphs, or a spring drought may reduce host fitness that nymphs require to successfully develop.

Recommendations

Scout for egg masses to consider population potential for the next season.

Research Needed

Conduct studies to better understand these influencing factors, enabling prediction of future SLF pressure.
Quantify how egg mass counts may or may not predict future SLF population levels.

Management (SLFMG, pages 8–16)

Many management practices effectively kill SLF, but achieving control can be challenging because:

No comprehensive control strategy currently exists to ensure successful management in every situation.
There is no known intentional intervention method that will provide management over large areas.
Managing SLF on one property will not prevent additional SLF from moving in from other properties.

Recommendations

Determine expectations for SLF management before implementing control measures.
Follow IPM practices (SLFMG, page 9). Choose cultural or physical/mechanical control options before resorting to the careful use of the least toxic, effective, registered insecticides available.
Always read and follow pesticide label directions.
Do not recommend or use home remedies.

Research Needed

Investigate area-wide approaches to treatment, including size of treatment areas needed to see population impacts

Cultural Control

Can removal of TOH help manage SLF populations? TOH is highly attractive to SLF, and new populations are often first found on TOH. Although feeding on TOH is not required for SLF to develop, grow, and reproduce, research indicates a positive relationship between TOH and some fitness parameters. TOH removal may help reduce lanternfly numbers in specific locations, but this effect has not been specifically researched, nor is it known how far from the area the removal might impact populations. It is unknown if removing TOH is an effective area-wide SLF management option.

TOH is a challenging plant to remove successfully given its propensity for suckering from an extensive root system and its prolific production of seed that remains viable for many years. Removal attempts may not be cost-effective as an SLF management strategy, especially as it frequently requires many repeated attempts before the TOH population is effectively eliminated.

Recommendations

Consider removing TOH, especially if it is close to areas of concern (e.g., vineyards, plant production nurseries, and transportation corridors). Follow TOH management guidelines.
Promptly remove standing dead TOH to reduce hazard potential.
Watch for TOH killed by naturally occurring Verticillium in your area. A plant-diagnostic clinic may be able to confirm the presence of this plant pathogen.

Research Needed

Identify cues that attract SLF to TOH to develop lures that could be used for trapping.
Quantify the impact of TOH removal on SLF populations.
Continue work to develop Verticillium as a potential TOH biological control product.
Investigate how long Verticillium remains active in the soil after existing TOH is killed and if it can prevent reestablishment.
Determine if SLF can transmit the pathogenic Verticillium from infected to uninfected TOH.
Continue work on biological control options for TOH management.

Biological Control: Support Natural Enemies of SLF (SLFMG, page 9)

Some insects, spiders, and birds are natural enemies of pests, including SLF. We commonly see predatory wheel bug (a type of assassin bug) egg masses near SLF egg masses. A parasitoid wasp, Ooencyrtus kuvanae, which was introduced in North America in 1908 for spongy moth control, also attacks SLF eggs. However, we have not quantified either of these natural enemies making a significant impact on reducing SLF populations. There are other known parasitoid wasps that attack SLF eggs or nymphs in their native range (parts of Asia). Some are under evaluation as potential biocontrol agents for potential release in the United States. Currently, an exotic parasitoid wasp that attacks SLF nymphs seems most promising, and research continues in this area.

Orange colored, newly emerged wheel bug nymphs — Figure 7. Wheel bug nymphs emerging. Credit: Brian Walsh

Recommendations

Natural enemies are beneficial, and their presence is a sign of a diverse and healthy environment. Conserve naturally occurring generalist predators by incorporating diverse plant life into landscapes and avoid the use of pesticides with high toxicity and long residual activity.
Avoid unnecessary insecticide applications to control SLF that may kill natural enemies.

Research Needed

Expand studies to evaluate the potential use and impact of endemic and exotic parasitoids, predators, and natural enemies.

Recommendation

Due to inconsistent results, we do not currently recommend B. bassiana for management of SLF.

Research Needed

Continued evaluation of entomopathogens for activity against SLF, including B. bassiana, Metarhizium species, and others.
Identify environmental conditions, application methods, lifecycle timing, and strains of entomopathogens that could optimize efficacy.

Mechanical Control: Finding and Destroying SLF Eggs (SLFMG, page 10)

The value of mechanical SLF egg destruction is limited. SLF eggs can be destroyed by scraping into alcohol or smashing; however, egg destruction alone cannot manage a large population of lanternflies. Most of the eggs found on trees are located above in the canopy and cannot be safely reached for scraping. Additionally, eggs are deposited on many surfaces and are frequently in protected areas that are hard to find. Chipping tree debris containing viable lanternfly egg masses has been confirmed to kill lanternflies if the chips are limited to less than 1 inch in size. Other chip sizes and mulching techniques were not tested.

SLF egg masses on a branch — Figure 9. Weathered egg masses attached to a branch in the spring prior to hatch. The covering surface is cracked but still intact, indicating that the eggs have not yet hatched. Credit: Emelie Swackhamer

Recommendation

Mechanical destruction is an easy way to kill SLF in the egg stage. This method is often used by volunteers and community groups to generate interest for public education and action.

Research Needed

Explore new tools and techniques for finding and destroying egg masses.
Evaluate how other standard mulching methods may affect SLF egg viability on debris.
Investigate controlled burning as a potential egg destruction

Mechanical Control: Traps (SLFMG, pages 11–12)

Traps can capture and kill large numbers of SLF. Trapping SLF may assist in protecting individual vulnerable plants from excessive lanternfly feeding, but the extent of protection this may provide is unknown and likely provides limited impact on the overall populations.

Recommendation

Trapping is most effective against nymphal stages of SLF.
Optimize trap construction to prevent bycatch of nontarget creatures.

Research Needed

Evaluate effectiveness of trap device by life stage.
Evaluate trapping efficacy on population numbers and area of protection.
Improve trap designs and perform comparative studies.
Identify and develop attractants.

SLF circle trap — Figure 10. A modified circle trap can be used to trap SLF on posts and trees with minimal risk to non-target organisms. Credit: Emelie Swackhamer

Using Insecticides for SLF (SLFMG, pages12–16)

Killing spotted lanternflies with insecticides is easy; managing infestations is not.

Killing SLF Eggs with Ovicides

Ovicide efficacy depends on two application variables—the concentration of the active ingredient and the thoroughness of coverage. In trees, most of the egg masses are located high in the canopy and do not receive complete pesticide coverage when using common application methods.

Recommendation

On a landscape scale, effective control is unlikely using available ovicides at labeled rates and common application methods.

Research Needed

Explore new or improved ovicide application methods, timing, and products.

Contact Insecticides

Efficacy trials across the spectrum of insecticide options demonstrate that many commercially available products can cause significant SLF mortality when applied according to the label instructions. However, reliable recommendations for successful long-term, wide-area management of SLF have not been determined. Individual site use classifications (i.e., food crop, forest, nursery, ornamental trees, residential, etc.) will inform the applicator of product choices, application methods, mix rates, and timing, in accordance with the associated labels. Generally, insecticides with the longest residual efficacy (e.g., synthetic pyrethroids) can be the most harmful to nontarget arthropods, including pollinators, predators, and natural enemies.

Recommendation

Monitor sites frequently. Try insecticides with lower toxicity before opting for more toxic products.

Needed Research

Conduct additional efficacy testing of available products and new products, focusing on field trials.
Evaluate effectiveness of buffer contact sprays for management in nurseries, vineyards, shipping facilities, etc.
Evaluate how long it takes for SLF to reinfiltrate a treated area to inform reapplication needs.

Systemic Insecticides

Some systemic insecticides can be highly efficacious at killing SLF that feed on treated host plants. Thiamethoxam, dinotefuran, and imidacloprid are neonicotinoids that are effective at killing SLF when used as systemics (these active ingredients also have contact insecticidal efficacy). Once dry and fully absorbed by treated host plants, systemic insecticides should have little effect on nontarget insects that do not feed directly on the plant, potentially providing a safer alternative to broad-spectrum contact insecticides. Application methodology, rates, and differences in water solubility and mobility in host trees will impact the speed and duration of effectiveness. The duration of efficacy is dosage dependent. Because it is more water soluble, dinotefuran will move through plants to reach feeding lanternflies more rapidly than imidacloprid, which is less water soluble. The potential impact of systemic insecticide treatments on pollinator populations due to persisting residues in flowers formed the following season remains a concern.

Recommendations

Judicious use of systemic insecticides applied to preferred hosts can be helpful to provide seasonal management of local SLF populations.
Dinotefuran is often used because it works fast and provides extended efficacy.
In Pennsylvania, systemic insecticides may be applied as trunk injections to protect trees in sensitive wetland areas.
Preferred hosts, especially TOH, can be used as trap trees. To establish trap trees: 1. Locate preferred trees on the site. For reasons not understood, SLF seems to prefer some individual "hot" trees over others of the same species. Try to identify the specific trees that are most attractive to SLF based on how many are feeding on them. 2. If using TOH as a trap tree, destroy most of the TOH present, leaving only a few that are "hot" or most attractive to SLF. They will serve as trap trees. It is recommended that you try to kill all the female TOH because they produce seed and contribute to the spread of this invasive tree. 3. Treat the selected trap trees with the systemic insecticide dinotefuran in the late summer. Dinotefuran treatments become efficacious very quickly, so treatments can begin working in hours to days, allowing for reactive treatments on later-season hosts. Actively scout to determine the best time to treat the trees. Follow label directions or hire a licensed pesticide applicator. 4. A correctly treated trap tree can kill many SLF, with single trees documented to kill over 10,000 SLF in as little as 2 weeks.

Needed Research

Conduct efficacy studies on systemic insecticides, including rates, application methods, and expected duration of efficacy.
Determine the lowest effective rates to try to reduce the quantity of insecticide being used and to prevent underdosing of treatments.
Quantify systemic insecticide residue in pollen and nectar following applications and determine the potential impact on pollinator health.

Deciding if, when, and how to Treat for SLF: Management Scenario Examples (SLFMG, pages 8–9)

There are many things to consider when faced with an SLF infestation. Each situation is unique, but the following are some common situations and suggested actions to help you form a management plan for your site.

Situation:

Ornamental plant nurseries grow favorite host plants (e.g., maple, birch, willow, etc.). SLF can directly affect the appearance, health, and growth of these plants. Nurseries also grow plants that are not favorite hosts, but SLF may be present and possibly deposit eggs on them (e.g., conifers). To comply with quarantine regulations, plant producers must ensure that their stock is free of any living life stages of SLF.

Goals: Prevent SLF from damaging stock and keep stock clean to avoid shipping living SLF (including viable eggs).

Possible Actions: Regularly scout for SLF. Focus on favorite host plants. Monitor areas surrounding production fields for infestation and use control measures. If the surrounding property is not owned by the nursery, work with that property owner to explore the possibility of managing SLF in that area. Avoid trespassing on someone else’s property. It is illegal to apply pesticides on someone else’s property without their permission and the proper applicator license.

When adult SLF are flying, monitor tall vertical objects. Practice visual scouting but also use traps. Continue to monitor throughout the year to be aware of SLF moving through the site as nymphs or adults. Use insecticides to kill nymphs and prevent adult SLF from laying eggs on stock. Check for and destroy egg masses on stock but also on other objects like stakes, fences, poles, vehicles, tables, etc. Plants that are near finished size require more attention and protection to keep them free of SLF. When shipping during adult dispersals, try to load trucks in the morning when SLF are less likely to be flying. Tarp orders that have been picked and inspected with fine meshed screen if they are going to be left outside before loading.

Situation:

A large specimen TOH is the only tree in the backyard of an urban residence, and it is the only shade tree for multiple properties. This tree is valued by the community, and the residents do not want it to be removed. The tree is inundated with SLF, honey dew and sooty mold are covering the area below the tree, a white, foul-smelling froth is at the base, and stinging insects are present.

Goal: Protect the tree from SLF damage and preserve the value of this landscape feature.

Possible Actions: Use traps to destroy nymphs. Consider treating the tree after bloom with a systemic insecticide (e.g., dinotefuran). Consult with a certified arborist to assess if the tree is a potential hazard. Begin a succession plan to replace this landscape feature. Promptly remove standing dead TOH to reduce hazard potential.

Situation:

A large shopping center has red maple trees planted in parking lot islands, and the other trees are not preferred hosts. The trees are stressed from hot and dry conditions and are planted poorly (too deep) in small areas surrounded by asphalt. During the fall of the previous year, many adult SLF flew into the area and quickly accumulated to feed on the preferred maples.

Goals: Help the maple trees survive the added stress of SLF feeding, prevent or mitigate SLF annoyance for shoppers, and prevent SLF hitchhiking on vehicles leaving the shopping center.

Possible Actions: Correct the planting situation if possible. Consider a proactive treatment using a systemic insecticide to provide long-lasting efficacy against the feeding adults. Monitor populations to assess risk (huge moving populations versus few SLF) and develop a management strategy for next year based on these observations. If the maple trees are in poor health and the SLF nuisance issues are overwhelming, consider replacing them with appropriate, alternative trees that are less preferred by SLF (e.g., honey locust, Zelkova, oak, etc.).

Situation:

Public spaces and event venues have outdoor areas that may include SLF-preferred trees and other vegetation, as well as structures such as buildings, outdoor entertainment facilities, and parking lots. During the adult SLF dispersal period, large numbers of SLF gather on trees and on structures, creating a nuisance situation for visitors.

Goal: Reduce the nuisance impact of SLF and avoid spreading SLF from these sites.

Possible Actions: Have a plan in place before SLF arrive on the site. How you choose to react depends on the use and guest expectations for the site.

One option is to simply be patient. Remember, dispersal flight behavior of adult SLF may only last for a week or two and the phenomenon will pass. Some SLF will die at the site. To avoid unsightly, dead insects and the unpleasant odor that can be associated with large numbers as they decay, remove the dead SLF. The rest will eventually move away. It is important to remember that SLF will not damage the structure of buildings, and insecticide applications are not needed to protect a building from structural damage.

If SLF create a nuisance that is not tolerable, there are insecticide management options available. All applications must be done in accordance with your state's pesticide regulations and the label directions. Know which trees are preferred hosts and consider treating them with a registered systemic insecticide. Consider using a contact insecticide that is registered for the specific site you intend to target (for example, outdoor landscape ornamentals, public or commercial buildings, recreational areas, etc.). Some states also require that the insect you want to control be listed on the label. If you hire a pesticide applicator, be sure that the applicator is licensed to make applications on the sites being treated.

Educate guests to inspect their vehicles and remove hitchhiking SLF before leaving the property.

Situation:

A residential property has many young flowering trees. The SLF population was large the previous year, and nymphs are predicted to appear in the spring.

Goal: The resident wants to protect flowering trees from the stress of nymphal feeding and reduce the potential that SLF may spread to other areas.

Possible Actions: Scout for egg masses and safely destroy those in reach; use traps to monitor and remove some of the nymphs. If populations are very high and you determine that additional action is necessary, a contact spray of insecticidal soap or oil may help. To protect pollinators, avoid spraying plants when they are flowering.

Situation:

A manufacturing business in an industrial park is adjacent to a neighboring, unmanaged property where there are many TOH that are infested with SLF. When the SLF become adults, the business is inundated with them. This business stores the packaging material they use to ship their products outdoors. Adult SLF are laying eggs on the packaging material and flying into trucks that are being loaded.

Goal: Maintain business operations, avoid shipping SLF, and comply with quarantine regulations.

Possible Actions: Try to reduce the SLF population. Encourage the owner of the adjacent property to use recommended management options. If necessary, contact the State Department of Agriculture to see if they can intervene or facilitate. On the business site, work with the property owner to treat preferred host trees with a systemic insecticide to provide a long period of SLF population reduction. Move objects and equipment that are stored outdoors as far away from trees as possible. Consider using tarps or enclosures to protect objects from female SLF that are seeking sites to lay eggs. Use large fans in packaging and loading areas to blow away flying SLF. Load trucks at night and in the early morning when flight activity tends to be lower. Do not leave trucks open any longer than is necessary. Contact insecticides may be used to kill SLF in shipping areas. Be sure insecticides are registered for the application site and follow all label directions. Inspect all shipments before they leave the site. Look for and remove all life stages (nymphs, adults, and/or eggs). Tell the recipients that the shipment came from within an area under quarantine for SLF. Include information for the recipients about SLF and provide a contact number for them to report any SLF that was shipped accidentally. Designate a person who is trained to manage shipping operations to respond to customer concerns and who will work with the state's Department of Agriculture to ensure compliance with regulations.

Prepared by Brian Walsh, extension educator, and Amy Korman and Emelie Swackhamer, former extension educators.
Large cover photo by Emelie Swackhamer. Small cover photo by AdobeStock.

Disclaimers
These recommendations are current as of June 2026 and will change as we learn more. We encourage you to stay up to date by visiting Penn State Extension's Spotted lanternfly website. Check the online version of this management guide and always look for the most up-to-date information. When using any pesticide, follow the pesticide label for directions, application rates, methods, and appropriate protective equipment. Remember, the label is the law.

Agenda

Spotted Lanternfly Management Guide Supplement