The spotted lanternfly, Lycorma delicatula, is an invasive planthopper from Asia that has recently captured public attention across the United States. First detected in Pennsylvania in 2014, this insect has rapidly spread across various states, posing significant concerns for agriculture and ecosystems. Its distinctive appearance, with gray forewings spotted with black and striking red hindwings visible in flight, often leads to questions about its nature and interaction with humans and pets.
Do They Bite?
Spotted lanternflies do not bite or sting people or animals. They are not venomous and are not known to transmit diseases to humans or household pets.
These insects possess specialized piercing-sucking mouthparts, designed solely for extracting sap from plants. Their feeding mechanism is adapted for plant tissues, not for defense or aggression towards larger organisms like humans or animals. While their sudden appearance in large numbers can be startling, there is no direct physical threat from a bite.
Their True Impact and Behavior
Spotted lanternflies cause considerable damage to plants and agricultural industries. Both adult and nymph stages feed on the sap of over 70 different plant species, including grapes, apples, hops, maples, and black walnuts. This continuous sap extraction weakens plants, leading to reduced growth, oozing wounds, and branch dieback. In vineyards, heavy infestations can significantly reduce grape yields and even lead to vine death.
As these insects feed, they excrete a sugary waste product known as “honeydew.” This sticky substance coats plants, vehicles, and outdoor surfaces. Honeydew also promotes the growth of black sooty mold, which can cover leaves and inhibit photosynthesis, further compromising plant health. The presence of honeydew can attract other insects, such as bees, wasps, and ants. The primary impact is ecological and agricultural, affecting crops and trees.
What to Do When You See One
Encountering a spotted lanternfly can be concerning, but individuals can take practical steps to manage their spread. If you see an adult or nymph, kill it immediately by crushing or stomping. For egg masses, typically laid on flat surfaces like trees, bricks, or vehicles, scrape them off using a stiff object and place them in a sealed bag with rubbing alcohol or hand sanitizer.
Reporting sightings, especially outside established quarantine zones, is important for tracking the insect’s spread. Many state agricultural departments or extension offices provide online reporting tools or hotlines for this purpose. Before traveling from an infested area, inspect vehicles, outdoor equipment, and any items stored outside for hidden egg masses or hitchhiking insects. This vigilance helps prevent accidental transport to new regions, slowing the expansion of this invasive species.