Invasive species are one of the biggest threats to our native ecosystems, agriculture and commerce across the country. Invasive species can be any type of living organism — bacteria, fungi, animals, plants. Species that grow and reproduce quickly, spread aggressively, or have the potential to do so are labeled invasive. Early detection of new pests is crucial in preventing the spread of invasive species.
Invasive insects are particularly challenging to manage, as many gardeners, farmers and natural resource managers can attest. With their ability to fly and reproduce in large numbers — often in multiple generations per year — an introduced insect can sometimes become a scourge in a relatively short period of time. In our area, we need look no further than our yards or fields to see how devastating fire ants have become, or to the devastation of our forests caused by the hemlock wooly adelgid.
A new species of concern is the spotted lanternfly (Lycorma delicatula), native in Asia and first detected in Pennsylvania in September 2014. Since then, there have been confirmed detections in six more states in the Mid-Atlantic and Northeast in 2017 and 2018. The spotted lanternfly prefers to feed on the invasive Tree-of-Heaven (Ailanthus altissima), which might be considered a good thing, but unfortunately it has a wide host range of over 70 species of plants and trees, including apples, peaches, grapes, pine, oaks and other hardwoods. This wide host range makes it a real threat to Georgia’s agriculture and environment.
Spotted lanternflies are not known to bite or sting people, pets or livestock. Instead, they do their damage by feeding on the sap of plants; when populations are high they can cause significant damage. This feeding also leaves behind a sticky, sugary residue called honeydew that promotes the growth of sooty mold. The good news, and perhaps the reason it hasn’t reached us yet, is that it is a poor flier. It is a hitchhiking pest, however, and will lay eggs on almost any surface.
Spotted lanternflies go through four nymph stages during which they are incapable of flight. In the first three stages they are about the size of a pencil eraser with white spots on a black body. Upon reaching the final nymph stage they become larger, turning red in color with distinct patches of black with white spots. The adult lanternfly is a leafhopper with wings about one inch long. Adults have grey wings with black spots. When the wings are open, they reveal bright red underwings, making the insect quite distinctive and attractive. Adults and nymphs will frequently gather in large numbers on host plants. They are easiest to spot at dusk or night as they move up and down the trunk of the plant.
The USDA, Pennsylvania Department of Agriculture and Penn State Extension Service are working on an aggressive control initiative to eradicate the pest and prevent its spread. There is presently a quarantine for 14 counties in southeast Pennsylvania affected by SLF. They are actively treating locations where SLF has been reported by working from the outer edges where populations are small, then moving inward towards the center of the quarantine zone. They are also treating areas where populations are high and targeting areas denoted as high-risk pathways which may contribute to moving the insect out of the quarantine zone.
Please be on the lookout as summer break leads to more interstate travel, with millions hitting the road each year. While you personally may not have passed through the areas of known SLF infestation, a neighbor or delivery driver who uses a personal vehicle might well have.
If you find an insect you suspect is the lanternfly, please contact me or your nearest Extension office to have the specimen identified.