The spotted lanternfly, an invasive insect from Asia, has been working its way toward our area since 2014, when it began taking its toll on vineyards, orchards and home landscapes in southeast Pennsylvania. In Virginia, it was first detected in the Winchester area—at the northern tip of the state—in 2018. It steadily hitchhiked its way to other localities, mainly along the Interstate 81 corridor, and was confirmed in Albemarle County in the summer of 2021.
At that time, local residents were asked to be on the lookout for the pest and to report any sightings to Virginia Cooperative Extension. No longer. “We’ve been getting lots of calls about it this year,” said Carrie Swanson, VCE unit coordinator and extension agent for Albemarle and Charlottesville. “We have them all over the county at this point.”
Now that it’s here, there and everywhere in our community, what can we expect? That depends on how well we get ahead of the problem.
The spotted lanternfly (Lycorma delicatula, shown at its immature and mature nymph stages below) is not a fly but a planthopper, related to aphids, leafhoppers and cicadas. Fortunately, it does not sting or bite, but it does feed on plant sap with its piercing mouthparts. By mid-summer, when it molts from its flightless nymph stage to winged adult, it can drill through a tree’s bark to get at the vascular system. At peak infestation, hundreds will latch onto a single tree, robbing it of vital nutrients. A mature, healthy tree can withstand this onslaught, but a young sapling can be pushed into decline, making it more susceptible to other stressors such as drought and disease. 
The spotted lanternfly poses an especially serious threat to our local winegrowers. SLF feeding can kill grapevines by reducing their ability to survive through winter. The trees in our local orchards are also at risk.
In home yards and gardens, perhaps the most annoying damage comes from honeydew—the sugary waste excreted by the insects as they feed. It can rain down from heavily infested trees, leaving a sticky coating on cars, patio furniture, children’s play sets and barbecue grills. Honeydew attracts yellowjackets and other stinging insects, takes on a rank odor as it ferments, and is colonized by black sooty mold, creating a mess that is difficult to clean up and makes it unpleasant to be outdoors.
Eric Day, a Virginia Tech entomologist at the forefront of the state’s battle against the spotted lanternfly, describes our situation in Albemarle County as the “leading edge” of the invasion. That means we can still take action to blunt the impacts.
“At the leading edge, you can be more proactive,” said Day, who is manager of Virginia Tech’s Insect ID Lab. “You can keep an eye out for it and spot spray if populations seem to pop up. It’s also where we get a lot of inquiries from people trying to gather as much information as they can, to really be on top of it.”
Professor Day and his colleagues are making sure that information is readily available. The online resources they have produced include “Best Management Practices for Spotted Lanternfly in Yards and Landscapes” (Virginia Cooperative Extension publication ENT0-344NP) and more recently “Homeowner Suggestions for Managing Spotted Lanternfly” (VCE publication ENTO-586NP). Among other things, these guides tell you how to recognize the insects at different life stages, when they will emerge during the year, and when to apply appropriate treatments. For an even deeper dive on this issue, search online for Penn State Extension’s “Spotted Lanternfly Management Guide.”
At this early point in the invasion, one of the most effective ways we can suppress the pest is to take away its favorite host plant, tree of heaven (Ailanthus altissima). Unfortunately, eliminating this exotic invasive from our properties is easier said than done. Small seedlings and their roots can be pulled up by hand, but cutting a mature Ailanthus will merely result in more trees sprouting up around the stump. As one of our local Tree Stewards likes to say, cutting down a tree of heaven will just make it mad.
Our local Cooperative Extension office has posted a YouTube video that provides step-by-step instructions for how to identify this plant and how to apply the right kind of herbicide in the right way to kill just this tree. The presenter is Adam Downing, the extension agent who first detected SLF in Albemarle County in 2021. Mid to late summer is the optimum time to deploy the methods he recommends in the video, including “hack and squirt.” This entails making multiple cuts with a hatchet around the trunk of the tree and then squirting an appropriate solution of herbicide in each of the cuts. The tree typically succumbs in about two weeks. The video includes instructions for how to handle chemicals safely.
Blue Ridge PRISM (Partnership for Regional Invasive Species Management) also offers a helpful factsheet on how to identify and remove tree of heaven. Search for it on their website, blueridgeprism.org.
Ailanthus may be the spotted lanternfly’s favorite host, but the pest is fond of many other trees and shrubs in our region, especially red maples, silver maples, black walnuts and black cherries. It is also drawn to woody vines such as Virginia creeper (Parthenocissus quinquefolia), a member of the grape family. Mark Sutphin, extension agent for Winchester and Frederick County—ground zero for the invasion in Virginia—noted that early on he was most likely to find the insect on tree of heaven with Virginia creeper climbing its trunk.
Almost inevitably, the spotted lanternfly will show up in your yard. Don’t hesitate to kill it. Given the insect’s speed and agility, you should keep a flyswatter handy. (To spread the word about the spotted lanternfly, the Piedmont Master Gardeners hand out these flyswatters at local farmer’s markets and other venues. Fern Campbell photo)
The next step is to assess vulnerable plants in your landscape, such as grapes and young maples, and monitor them closely. If an infestation does occur, turn to the VCE publications mentioned above to find appropriate treatments and when they should be used during the insect’s lifecycle.
These include dormant oil that can be applied to egg masses on trees during the winter before budbreak. Contact insecticides can be spot sprayed on nymphs and adults when they appear on plants in the spring and summer and may have residual benefits into the fall. Systemic insecticides, which enter a tree’s circulatory system by way of trunk spray, trunk injection or soil drench, will kill the pest when it feeds on the sap. Organic options such as neem oil and insecticidal soaps are also effective but may require repeated application.
Whichever treatment you select, take care to avoid harm to pollinators and other beneficial insects. For example, always wait to apply systemic insecticides until after a tree’s bloom time and after plants under the tree have completed flowering. And consider carefully whether chemical treatments are the right choice for your situation.
“We’re not advocating that people start spraying willy-nilly all over the place,” said Sutphin, one of the co-authors of the VCE guides. “Unless you’re managing grapes or have a specific scenario that needs to be addressed, it may not be justified.”
Besides, he added, spraying isn’t a be-all and end-all solution. “Because of the way these pests exist in the landscape, they’ll keep reinvading your property.”
Charlottesville and Albemarle County are among the Virginia localities under an official “quarantine” aimed at preventing the spread of the spotted lanternfly via commercial vehicles. The adult insects have emerged and will be laying their eggs through the fall. We can all help stop these hitchhikers by keeping our own vehicles clean and by scouting for egg masses (shown here) in our wheel wells and truck beds, and then scraping them off and stomping them before leaving town.
To learn how to recognize and destroy the egg masses, take a look at Penn State Extension’s helpful video, “How To Remove Spotted Lanternfly Eggs.”
Spotted lanternfly photos courtesy of extension agent Mark Sutphin
