Spotted Lanternfly In MD: How To Spot This Invasive Insect

MARYLAND — Spotted lanternflies are out in full force in Maryland this summer, but how easy is it to spot the destructive planthoppers once they lay claim to your favorite backyard tree?

The spotted lanternfly, an invasive species native to eastern Asia, was first found in Maryland in 2018 in Cecil County. It has since spread to Allegany, Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Charles, Frederick, Garrett, Harford, Howard, Kent, Montgomery, Prince George's, Queen Anne's, Talbot, Wicomico, and Washington counties and Baltimore City, according to the Maryland Department of Agriculture.

Adult insects have polka-dotted forewings and bold red underwings, giving them a distinctive appearance. Although it has the allure of a butterfly, the insect’s looks are deceiving.

Davey Tree Expert Company arborist Lou Meyer recently took a stroll through Patuxent River State Park in Montgomery County and shared with WTOP what Marylanders should look for to identify the pest.

Voracious eaters, spotted lanternflies feed on about 100 plant and tree species, including economically important crops such as grapevines, apple orchards, hops ornamental landscape plants, along with multiple tree species.

During his walk with WTOP, Meyer pointed out an ailanthus tree, also known as the tree of heaven, covered in the spotted insects.

“They love feeding on the sugars, the carbohydrates, that the tree is producing,” Meyer told WTOP.

While feeding on plants, spotted lanternflies secrete a liquid known as honeydew. The liquid can develop an intense, rotten odor as it ferments and causes black, sooty mold, which can cover leaves and inhibit photosynthesis. Sooty mold can also cover manmade structures and be difficult to remove.

Meyer told WTOP the honeydew comes from a spotted lanternfly's wings when they're spread.

“On a heavily infested tree, it looks like it’s raining on a clear day,” Meyer said.

Now through September, spotted lanternflies take on the distinct red coloration and grow to about an inch long and one-half inch wide. In the adult stage, you may not see the flash of red until they take flight. While resting, the grayish forewings with black spots cover the colorful hindwings.

While experts often urge people who see spotted lanternflies to destroy them, Meyer said native birds are also discovering how tasty they are.

“Now they’re starting to eat them, so nature is starting to find more of a balance,” Meyer told WTOP.

In Maryland, the Department of Agriculture issued a quarantine for 20 counties where the spotted lanternfly is present. The purpose of the quarantine is to stop the spread of the pest to other counties.

"All other life stages of this insect, from nymphs to adults, can fly, hop, or drop into a vehicle – meaning that vehicles and equipment can easily and quickly help it spread," state officials said. "Therefore, a quarantine of an area found to be infested with the spotted lanternfly means that any material or object that could harbor the pest cannot be moved without taking precautions to prevent its spread."

Due to the quarantine, items including landscaping or construction waste, packing materials, plants, and outdoor items all require a permit to move within or from the quarantine area.

According to state officials, Marylanders should use this checklist for homeowners to determine if they have spotted lanternflies on their property.

"Thoroughly inspect all items presented on this list for any type of spotted lanternfly life stage and destroy all (lanternflies) that you discover," officials said. "This will help slow the spread of the insects to new areas."

Spotted lanternfly sightings should also be reported to the state through this online form.