The spotted lanternfly (SLF) is an invasive species that has generated widespread public concern across the United States. This striking insect, first discovered in Pennsylvania in 2014, is known for rapidly spreading and congregating in large numbers, which leads to questions about its potential danger to people and pets. The most immediate answer is reassuring: the spotted lanternfly is neither poisonous nor venomous to humans or common household animals. The insect’s primary threat is not physical harm, but the severe damage it inflicts on agriculture and the environment.
Are Spotted Lanternflies Toxic to People and Animals
Spotted lanternflies do not possess stingers, nor do they bite humans or household pets. They are not known to transmit any pathogens or diseases, making direct physical contact harmless. Their mouthparts are designed exclusively for piercing plant tissue to extract sap.
The insects accumulate bitter-tasting compounds called quassinoids from their preferred host plant, the Tree of Heaven, which acts as a deterrent to predators like birds. While not considered toxic to mammals, this accumulation makes the lanternfly unpalatable. If a pet were to ingest a spotted lanternfly, the bitter compounds would likely result in only mild and temporary stomach upset, such as vomiting, and is not life-threatening.
Identifying the Spotted Lanternfly
The adults are approximately one inch long, featuring light gray to tan forewings covered in distinct black spots. When the insect opens its wings, a bright flash of red is revealed on the hind wings, which are marked with black spots and a black tip.
Before reaching the adult stage, the insect progresses through four nymph stages. The first three stages appear as small, wingless insects that are completely black with bright white spots. The final nymph stage, or fourth instar, is much larger and displays a striking red coloration with prominent black patches and the same signature white spots.
Egg masses are typically laid in the late fall, consisting of 30 to 50 eggs covered in a protective layer of gray, putty-like material. This material eventually dries and cracks, resembling a patch of mud or dried plaster.
The Real Danger of the Spotted Lanternfly
Using a long, straw-like mouthpart, the insect pierces the bark and stems of plants to extract phloem sap. This sustained feeding, especially when large numbers of insects are present, stresses the host plant, leading to wilting, leaf curl, and a reduction in growth or fruit production.
The insect feeds on over 70 species of plants, including commercially valuable crops like grapevines, hops, and stone fruit trees. As the lanternfly consumes large amounts of sap, it excretes a copious amount of sugary waste known as “honeydew.”
This sticky substance coats the plant and anything beneath it, attracting other nuisance insects and fostering the growth of a black fungus called sooty mold. This mold is detrimental because it blocks sunlight from reaching the leaves, inhibiting the plant’s ability to photosynthesize and further weakening its health.
Mandatory Steps for Encountering the Insect
The public is strongly encouraged to take immediate action upon finding a spotted lanternfly. The protocol is “Stomp it, scrape it, report it.” Any adult or nymph spotted should be immediately crushed or swatted to prevent further feeding and egg-laying.
Egg masses found from late fall through spring must be scraped from the surface using a credit card, knife, or stiff putty tool. The scraped mass should then be destroyed by placing it into a container of rubbing alcohol or hand sanitizer, or by double-bagging and discarding it to ensure the embryos are killed.
Finally, all sightings, particularly those in new areas, must be reported to the state’s Department of Agriculture or local agricultural extension office. This helps officials track the invasion and implement control measures.