The appearance of spotted lanternflies has led to public questions about their potential to harm humans. Many people wonder if these insects pose a direct threat, such as biting. Understanding their characteristics and behaviors helps clarify their interaction with people and the environment.
Understanding Lanternfly Mouthparts
Spotted lanternflies do not possess mouthparts capable of biting humans or pets. Unlike mosquitoes or ticks, they are equipped with a piercing-sucking proboscis. This specialized appendage penetrates plant tissues to extract sap. Their mouthparts function like a tiny straw, incapable of breaking human or animal skin.
How Lanternflies Feed
Spotted lanternflies use their piercing-sucking mouthparts to feed on sap, specifically the phloem, from a wide variety of plants. They insert their proboscis into plant stems and trunks to access the sugary fluid. While they do not actively “suck” sap, natural pressure within the plant tissues causes the sap to flow into their mouthparts. This feeding primarily targets trees such as the Tree of Heaven, grapevines, fruit trees like apples and peaches, and various maples.
As they feed, spotted lanternflies excrete a sugary, sticky waste product known as “honeydew.” This honeydew accumulates on plants, outdoor surfaces, and vehicles, promoting the growth of black sooty mold. Sooty mold covers leaves, reducing a plant’s ability to perform photosynthesis and affecting its health. Honeydew also attracts other insects like bees, wasps, and ants, which can create nuisances.
Why Lanternflies are a Concern
While spotted lanternflies do not bite or sting people, they are an invasive species posing a threat to agriculture and natural ecosystems. They were first detected in Pennsylvania in 2014 and have since spread to multiple states. Their feeding weakens plants by depleting nutrients and causing sap to ooze from wounds, leading to wilting, leaf curling, and dieback. In severe infestations, particularly on grapevines, this feeding can lead to reduced crop yield, loss of winter hardiness, and even plant death.
The economic implications are substantial for industries reliant on affected plants. The grape, fruit tree, and logging industries face considerable risks. In Pennsylvania, the estimated annual economic impact of spotted lanternfly damage on agriculture could reach over $42 million statewide, with potential losses escalating to hundreds of millions if the pest continues to spread. Their rapid spread and broad host range make them a concern for agricultural stability and natural resource preservation.
What to Do About Lanternflies
Public participation is important in managing the spread of spotted lanternflies. If you encounter one, report the sighting to your local agricultural department or extension service, especially if outside a known quarantine zone. It is also recommended to kill any adult or nymph spotted lanternflies you see by squashing them.
For egg masses, typically laid in the fall on various surfaces as a grayish, mud-like coating, physical removal is effective. Scrape the egg masses off the surface using a stiff tool like a credit card or putty knife. Then, destroy them by placing them in a resealable bag containing rubbing alcohol or hand sanitizer. This ensures the eggs are killed and prevents them from hatching in the spring. While sticky bands can trap nymphs and adults as they climb trees, use them with caution and consider adding a barrier to prevent trapping beneficial insects or small animals.