Spotted lanternflies cannot bite you. Their mouthparts are physically incapable of it. Instead of jaws or teeth, they have a needle-like bundle of stylets designed to pierce plant tissue and suck out sap, much like a tiny straw pushed into a stem. The worry most people have when they see these large, colorful insects is understandable, but the real damage lanternflies inflict has nothing to do with humans or pets and everything to do with the plants they feed on, the sticky mess they leave behind, and the economic toll that follows.
Why Lanternflies Cannot Bite
Spotted lanternflies belong to the order Hemiptera, a group of insects that includes cicadas, aphids, and stink bugs. None of these insects have chewing mouthparts. Instead, the lanternfly’s feeding apparatus consists of a cone-shaped labrum, a tubular labium, and a stylet fascicle made up of two interlocking maxillary stylets partially surrounded by two shorter mandibular stylets. Both nymphs and adults use this structure to pierce plant tissue and extract phloem sap from vascular bundles in young stems and leaves.1PLoS ONE. Structure and Sensilla of the Mouthparts of the Spotted Lanternfly Lycorma delicatula (Hemiptera: Fulgoromorpha: Fulgoridae), a Polyphagous Invasive Planthopper Think of it as a hypodermic needle rather than a set of jaws. The stylets are thin enough to slip between plant cells but not built to puncture human skin in any meaningful way.
If a lanternfly lands on your arm and you feel a slight poke, that is the insect probing with its stylets, possibly mistaking your skin for a plant surface. It will not draw blood, inject venom, or leave a wound. Lanternflies are not venomous or poisonous to humans. They do not sting. They carry no known pathogens that affect people. You can brush one off without concern.
What They Actually Do to Plants
The damage spotted lanternflies cause starts with their feeding. They are phloem feeders, meaning they tap into the plant’s nutrient-transport system and drink the sugary fluid that carries energy from leaves to roots and growing tissues. A single lanternfly does not drain much, but these insects aggregate in enormous numbers. Dozens or even hundreds can cluster on a single tree trunk or vine.
Research on grapevines shows that prolonged phloem feeding by large populations of adult lanternflies can cause carbon limitation in the plant, essentially starving it of the energy it needs to grow, ripen fruit, and prepare for winter. When feeding pressure is intense enough, the effects carry over into the following year, potentially reducing the vine’s ability to survive cold temperatures and produce a normal crop.2PubMed Central. Prolonged phloem feeding by the spotted lanternfly, an invasive planthopper, alters resource allocation and inhibits gas exchange in grapevines Vineyards have suffered the most visible damage in the eastern United States, where lanternfly populations exploded after the insect was first detected in southeastern Pennsylvania in 2014.3PubMed. Perspective: shedding light on spotted lanternfly impacts in the USA
Honeydew, Sooty Mold, and the Mess Underneath
Phloem sap is rich in sugars but low in protein, so lanternflies need to process large volumes of it to get enough nutrition. The excess gets excreted as honeydew, a sticky liquid that rains down from infested trees and vines onto leaves, cars, patios, and anything else below. If you have ever walked under a heavily infested tree and felt a fine mist on your skin or noticed your shoes sticking to the sidewalk, that was honeydew.
The honeydew itself is annoying but relatively harmless to people. For plants, however, it creates a secondary problem. A group of fungi collectively called sooty mold colonizes honeydew deposits on leaf surfaces, forming a dark coating that blocks sunlight. In forest understories beneath infested trees, researchers found that sooty mold accumulation was highest near the trunk and decreased toward the canopy edge, though it varied widely from tree to tree. Light transmission through affected leaves dropped by roughly a third of a percent for every one-percent increase in sooty mold coverage.4PubMed Central. Sooty mold deposition and leaf-level light attenuation beneath trees infested with Lycorma delicatula That might sound small per unit, but when mold covers half a leaf or more, the cumulative reduction in photosynthesis becomes significant. The combination of direct feeding and sooty mold shading is what makes lanternfly infestations so damaging: the insect drains the plant’s resources from above while mold cuts off the sunlight the plant needs to replace them.3PubMed. Perspective: shedding light on spotted lanternfly impacts in the USA
Which Plants Are Most at Risk
Spotted lanternflies are generalists. They feed on more than 70 plant species, which is part of what makes them such a headache for agriculture and urban forestry alike. But they do have preferences, and those preferences shift as they grow. Early-stage nymphs feed on a wide variety of hosts. By the time they reach the fourth instar stage in late summer, black walnut becomes a dominant host, though tree-of-heaven remains a consistent favorite throughout. Once adults emerge in mid-to-late August, they concentrate heavily on tree-of-heaven, with a sizable portion also feeding on wild grape.5Environmental Entomology. Oviposition Substrate Selection, Egg Mass Characteristics, Host Preference, and Life History of the Spotted Lanternfly (Hemiptera: Fulgoridae) in North America
Tree-of-heaven, itself an invasive species from China, plays a central role in the lanternfly’s lifecycle. It seems to be the preferred host for adult feeding and egg-laying, and areas with dense tree-of-heaven stands tend to harbor the largest lanternfly populations. This creates an ironic dynamic: one invasive species fueling another. For homeowners, the practical takeaway is that removing tree-of-heaven from your property can reduce the attractiveness of your yard to lanternflies, though it will not eliminate them if other suitable hosts are nearby.
Grapes, hops, apples, stone fruits, maples, willows, and oaks are all on the menu. Vineyards have been hit hardest in terms of documented crop damage, but the insect’s willingness to feed on ornamental and hardwood trees means suburban neighborhoods and managed forests are not spared.
The Economic Toll
Lanternfly damage translates into real financial losses. An assessment of potential impacts on New York State’s grape industry estimated that during the first year of infestation, total losses across the state could reach about $1.5 million, with the Chautauqua-Lake Erie region alone accounting for roughly $1.2 million of that figure. In subsequent years as populations grow, losses escalate. By later stages of infestation, annual losses in New York’s grape industry could climb to around $8.8 million.6Oxford Academic / Journal of Integrated Pest Management. Assessing the potential economic impacts of spotted lanternfly (Hemiptera: Fulgoridae) infestations on grape production in New York State
Those figures cover only one crop in one state. Lanternflies are now established or have been detected across much of the mid-Atlantic and northeastern United States, and their range continues to expand. The aggregate impact on agriculture, forestry, landscaping, and outdoor recreation across the affected region is harder to pin down but is clearly in the hundreds of millions of dollars when you factor in control costs, quarantine enforcement, and lost productivity. Beyond farming, property owners deal with honeydew-coated surfaces, swarms of insects on outdoor structures, and the general nuisance of living in a lanternfly hotspot.
An Unexpected Side Effect of Honeydew
Not every consequence of lanternfly feeding is straightforwardly negative for every organism. Honeydew and the sap-exuding wounds that lanternflies create on tree-of-heaven provide carbohydrate resources that attract a range of other insects. Observations at feeding sites found that the visitors were predominantly wasps and other Hymenoptera, along with flies. Pollinators, parasitoids, and various other invertebrates all showed up to feed on the sugary deposits.7Oxford Academic. Honeydew and feeding-wound exudate from invasive spotted lanternfly (Hemiptera: Fulgoridae) on invasive tree-of-heaven (Sapindales: Simaroubaceae) subsidize North American pollinators, parasitoids, and other invertebrates
That might sound like a silver lining, but the picture is complicated. Among the insects attracted to honeydew, the European hornet was abundant and showed aggressive behavior toward native consumers, including pollinators. So while honeydew creates a temporary food source, it can also set up competitive dynamics that disadvantage native species. The ecological ripple effects of a large-scale invasive insect are rarely simple.
How They Spread So Fast
One of the most frustrating things about spotted lanternflies is how quickly they colonize new areas, and the main reason is us. Modeling studies have found that human-mediated dispersal is the primary driver of the insect’s spread. When researchers simulated lanternfly movement without any hitchhiking on vehicles, their models could correctly predict the observed spread pattern only about a third of the time. Adding even a small amount of human-mediated movement, as few as three successful hitchhiking events per year, boosted prediction accuracy to 92%. The distribution of lanternfly populations closely follows major roads and highways, which also happen to pass through areas with high densities of tree-of-heaven.8Scientific Reports. Human-mediated dispersal drives the spread of the spotted lanternfly (Lycorma delicatula)
The most common hitchhiking mechanism is egg masses. Female lanternflies lay egg masses on flat surfaces, not just tree bark but also vehicles, shipping containers, outdoor furniture, stone, and firewood. The egg masses are covered in a putty-like coating that hardens into a mud-colored layer, making them easy to miss. One egg mass moved on a pallet of lumber or the underside of a trailer can establish a new population hundreds of miles away. Checking your vehicle and any outdoor items before traveling out of a quarantine zone is one of the most effective things an individual can do to slow the spread.
Biological Control Efforts
Chemical insecticides work against lanternflies, but spraying broad-spectrum pesticides across forests and urban areas is impractical and ecologically harmful. Researchers have been exploring biological control as a more sustainable long-term strategy. Two main approaches are under investigation: parasitoid insects and fungal pathogens.
On the parasitoid front, scientists are evaluating insects from the lanternfly’s native range in China. An egg parasitoid called Anastatus orientalis is being studied for possible release in California as a proactive measure in case the lanternfly establishes there.9Biological Control. Proactive biological control of spotted lanternfly: Parasitism and host feeding behavior of Anastatus orientalis (Hymenoptera: Eupelmidae) on Lycorma delicatula (Hemiptera: Fulgoridae) egg masses A nymphal parasitoid, Dryinus sinicus, attacks lanternfly nymphs in China and is being evaluated for its reproductive potential and developmental characteristics as a candidate for U.S. introduction.10Annals of the Entomological Society of America. Developmental morphology and reproductive potential of Dryinus sinicus (Hymenoptera: Dryinidae), a promising biological control agent for spotted lanternfly The challenge with classical biological control is ensuring the introduced agent targets the pest without harming native species, a process that takes years of testing before any release is approved.
Fungal entomopathogens have shown more immediate promise. In the fall of 2018, two naturally occurring fungi, Beauveria bassiana and Batkoa major, drove localized population collapses in lanternfly populations in Berks County, Pennsylvania. Field trials using a commercial formulation of B. bassiana in a public park confirmed that the fungus can help suppress lanternfly numbers in both agricultural settings and natural areas.11Environmental Entomology. Applications of Beauveria bassiana (Hypocreales: Cordycipitaceae) to Control Populations of Spotted Lanternfly (Hemiptera: Fulgoridae), in Semi-Natural Landscapes and on Grapevines Further research has identified multiple naturally occurring strains of B. bassiana in Pennsylvania’s lanternfly populations, with some strains performing better against nymphs and others more effective against adults.12PubMed Central. Cryptic diversity and virulence of Beauveria bassiana recovered from Lycorma delicatula (spotted lanternfly) in eastern Pennsylvania The fact that these fungi are already present and killing lanternflies in the wild is encouraging, since it suggests natural population regulation may build over time as fungal strains adapt to the host.
What You Can Do at Home
If you live in an area where lanternflies are established, the most practical steps focus on reducing populations on your property and preventing accidental spread. Scraping egg masses off trees, fences, and outdoor structures between fall and spring is surprisingly effective at reducing local numbers. Each egg mass contains 30 to 50 eggs, so every one you destroy eliminates dozens of potential nymphs. Drop the scraped material into a bag with rubbing alcohol or hand sanitizer to kill the eggs.
Circle traps wrapped around tree trunks catch nymphs as they climb to feed. Sticky bands work too, though wildlife-safe designs with a screen mesh cover are recommended because traditional sticky traps can inadvertently catch birds and small mammals. Removing tree-of-heaven from your property, or treating it with herbicide while leaving one or two “trap trees” as bait, is a strategy many extension services recommend. The trap trees concentrate lanternflies where they can be targeted with insecticide or biological controls rather than spreading across your entire landscape.
Reporting sightings matters, especially if you are outside the known range. Community-science tools, including smartphone apps that use GPS-tagged photos to map lanternfly distribution in real time, are helping researchers and pest management agencies track the insect’s spread and direct resources where they are needed most.13Smart Agricultural Technology. bioWatch: a computer vision system for community-based identification and reporting of spotted lanternfly life stage State departments of agriculture in affected regions maintain reporting hotlines and websites. A single early report from a new area can trigger a rapid response that prevents a full-blown infestation.
Are Lanternflies Dangerous to Pets
Dogs and cats sometimes eat lanternflies, which leads to understandable worry. There is no evidence that spotted lanternflies are toxic to pets. They do not produce defensive chemicals like some beetles or caterpillars, and they are not known to carry parasites that affect domestic animals. A dog that eats a handful might experience mild gastrointestinal upset simply because insects are not a normal part of its diet, but veterinary toxicology resources have not flagged lanternflies as a poisoning risk. The bigger concern in heavily infested areas is that pets tracking through honeydew-covered surfaces can bring sticky residue indoors, which is annoying but not hazardous.
Chickens and wild birds eat lanternflies opportunistically, and some homeowners in infested areas have noticed their flocks treating the insects as a snack. Whether birds and other predators can exert meaningful population-level control on lanternflies remains an open question. The insect’s large body size and tendency to aggregate in accessible locations make it a visible target, but its reproductive output is high enough that casual predation alone is unlikely to keep numbers in check.