Discovered in U.S. for the first time in 2014 in Pennsylvania, the spotted lanternfly (Lycorma delicatula) is a destructive insect, originally from Asia, that feeds on many different fruit, ornamental and landscape trees and crops.
It’s currently found in counties in 14 states, and has spread quickly across long distances.
“They use our transportation methods,” says Matthew Travis, national policy manager for the Spotted Lanternfly Program with USDA.
“They’re great hitchhikers that have moved efficiently to expand their range by laying eggs on surfaces such as nursery stock, autos, rail cars, trailers, campers, boats, and planes.”
Adults may cling to your clothing or car or fly into the open windows of vehicles.
In its native range, the spotted lanternfly is rarely a problem. But that’s because it has natural enemies that are not found in America. “Our goal is to manage the population we have and try to eradicate it. We want to limit its movement as much as possible until we have better tools for eliminating this pest,” says Travis.
The life cycle starts when spotted lanternflies hatch in spring, emerging as tiny black beetle-like bugs with white spots, then later red and black with white spots. They’re most conspicuous when they become inch-long flying adults in mid to late summer. Then you can see the vibrant red coloring on their backs and wings, says Travis.
Spotted lanternflies often congregate in huge numbers on the trunks of trees in the evening. In the fall, they lay brownish one-inch long egg masses that look like a mud smear. You can find them on flat surfaces such as vehicles, buildings, outdoor gear, and trees. (Learn to ID various life stages here).
Fortunately, lanternflies don’t bite or sting. They don’t harm people or pets in any way. But they’re a big, disgusting nuisance. “The issue is they impact your quality of life when you’re trying to enjoy your outdoor space. They may be present in heavy numbers eating and excreting honeydew and hopping all around you,” says Travis.
The honeydew—a sweet, clear liquid the lanternflies excrete as waste—attracts ants, wasps, and bees, which like to eat it. This can increases your risk for stings. ;
The sticky film can end up covering everything in your back yard. It has a strong fermented odor and can contribute to sooty mold buildup on grapes or tree fruits, which interferes with a plant’s ability to photosynthesize.
Here’s what else you need to know about the spotted lanternfly and what to do if you find them in your garden:
What Does Spotted Lanternfly Eat?
The spotted lanternfly has been found on trees such as almond, apple, cherry, walnut, maple, oak, willow. They’re especially damaging to grapes and have been documented in large numbers in vineyards.
The young nymph stages will feed on roses, perennials, vegetable and herb plants, too, but damage may not be noticed unless populations are very high.
Interestingly, the spotted lanternfly's preferred host is the tree-of-heaven, an invasive weed tree from the insect’s native range in Asia.
Tree-of-heaven thrives in soil that has been disturbed, such as along roadsides. The hardiness of this tree has helped further the spread of spotted lanternflies because it’s an aggressive grower which is difficult to eradicate. Because it is invasive itself and a host, this tree should be quickly removed if found on your property.
Will Spotted Lanternflies Kill My Plants?
Possibly, but it’s usually because they weaken the plant. “We know spotted lanternflies are a plant stressor,” says Travis. “They pull plant energy out, and then other factors such as drought, weather, or other insects may attack and cause plant mortality.”
What Should You Do If You Find Spotted Lanternflies?
If you positively ID these insects, kill them. “Any opportunity you have to eliminate them in your yard, do so,” says Travis. Stomp on the adults, and if you find the egg masses, scrape them off surfaces and smash them.
For large numbers, you can use sticky tape or a tree band around trunks of trees to capture them as they travel up trunks to feed. This is not always recommended, as you also may catch beneficial insects or even birds.
Circle traps (get DIY instructions here), which tunnel the insects into a container, are a better solution. Pesticides typically are not recommended. They will kill beneficial insects, too.
If you know you live in or have traveled to a quarantined area, you should check your vehicle, camping equipment and clothes for the adults or egg masses before traveling.
Most importantly, take a photo and report any sightings to your state’s department of agriculture or your local university coop extension service. (Find your local coop extension here.)
Even if you’re not completely sure if it’s a spotted lanternfly, it’s worth a call to ensure this pest doesn’t establish itself in new states.
Arricca Elin SanSone has written about health and lifestyle topics for Prevention, Country Living, Woman's Day, and more. She’s passionate about gardening, baking, reading, and spending time with the people and dogs she loves.
