The Spotted Lanternfly (Lycorma delicatula) is an invasive planthopper native to Asia (China, India, and Vietnam). It was first discovered in the US in Berks County, Pennsylvania, in 2014. Since then, it has spread rapidly across multiple states, largely by hitchhiking on vehicles and transported goods. While colorful, this pest poses a severe threat not to people or animals, but to the nation’s agricultural and forest industries. Its damage to plants and potential economic impact are the primary reasons for containment efforts.
Direct Threat to Humans and Pets
The Spotted Lanternfly is not physically harmful to people or domestic animals. It does not possess a stinger, nor are its piercing-sucking mouthparts capable of biting human skin. These mouthparts function like a tiny straw, designed only to extract sap from plant tissue.
There is no evidence that the Lanternfly carries diseases transmissible to humans or pets. While concerns about toxicity have been raised, no confirmed toxins have been identified. If a pet ingests one, the exoskeleton may cause temporary stomach upset or drooling. Preventing ingestion is advised as a general precaution against eating any wild insect.
The Primary Threat: Damage to Plants and Agriculture
The Spotted Lanternfly poses a threat due to its devastating effect on plants and the economy, particularly in agricultural regions. Both nymph and adult stages feed on the sugary sap (phloem) of over 70 different plant species. This feeding behavior, often occurring in massive swarms, weakens host plants by draining resources.
The insect is a serious agricultural pest due to its preference for commercially valuable plants. Grapevines are highly vulnerable; heavy infestations cause reduced yields, loss of winter hardiness, and plant death. Fruit trees (apple, peach, cherry) and hardwood trees (maple, walnut, willow) are also impacted by the concentrated feeding.
As the lanternfly feeds, it excretes excess sugar water as a sticky liquid called “honeydew.” This honeydew coats surfaces beneath the insects, including leaves and outdoor equipment. The sugary residue serves as a growth medium for sooty mold.
The sooty mold forms a thick, black layer that hinders photosynthesis. In agricultural settings, the mold contaminates fruit, making crops unmarketable and leading to substantial financial losses. The sticky honeydew and insect presence can also impact outdoor recreation and tourism.
Identification and Life Cycle
Recognizing the Spotted Lanternfly at different stages is important, as it undergoes distinct visual changes throughout its single-generation annual life cycle. The cycle begins with overwintering egg masses, which are laid in the fall and are often the primary means of long-distance spread. These masses contain 30 to 50 eggs and are covered with a gray, putty-like or waxy substance that eventually dries and cracks, resembling a smear of mud on any hard surface.
The eggs hatch in the spring (April to May), releasing the nymph stage, which goes through four instars. The first three nymph stages are small, wingless, and black with distinctive white spots. The fourth and final nymph instar, appearing in mid-to-late summer, is more striking, displaying bright red patches along with the black and white spots.
Adults emerge starting in late July or August and are approximately one inch long. When at rest, the outer wings are pinkish-tan with black spots. When the insect jumps or flies, the hindwings are exposed, revealing a bold pattern of black, white, and vibrant scarlet red. Adults continue to feed and lay eggs until they are killed by a hard frost in late fall or early winter.
What to Do If You Encounter a Lanternfly
The public plays an important role in slowing the spread of this invasive species. If you see a Spotted Lanternfly, you should immediately destroy it, which is often accomplished by stepping on it. Nymphs and adults can also be killed by swatting or crushing them.
For sightings outside of established quarantine zones, it is important to report the finding to state or local agricultural departments. Reporting procedures often require taking a photograph or collecting a sample of the insect for confirmation, which helps officials track the pest’s expansion.
Within quarantine areas, the focus shifts to compliance with regulations designed to prevent accidental transport. Before traveling, especially when leaving an infested area, it is mandatory to inspect all outdoor items for the insect or its egg masses. This includes checking vehicles, firewood, grills, outdoor furniture, and any equipment that has been left outside. Scraping off and destroying egg masses, often by placing them in a sealed container with rubbing alcohol or hand sanitizer, prevents the next generation from hatching.