UConn Extension On The Spotted Lanternfly: "An Invasion Of An invasive Insect"

STORRS, CT — In the words of Lauren Kurtz from the UConn. Extension Home Garden Education Office, this summer has been "an invasion of an invasive species."

And in some cases, it appears to be an infestation when there is a local concentration.

Yes, the spotted lanternfly has certainly made its presence this year in all Connecticut counties.

Connecticut residents may be seeing more spotted lanternflies this time of year, as the invasive insect has now been reported in all eight counties, according to a new UConn Extension fact sheet.

"It can be considered an infestation locally, like if there are high numbers of SLF in a backyard or neighborhood," Kurtz said. "Statewide, it's an invasion of an invasive insect."

The spotted lanternfly, an insect native to parts of Asia, was first detected in the United States in Berks County, PA, in 2014. Connecticut recorded its first report in Fairfield County in 2020. By 2025, the insect had been reported statewide, according to UConn Extension.

The insect poses a potential threat to Connecticut agriculture, particularly fruit crops, according to UConn Extension. Spotted lanternflies feed on plant sap and have been found on more than 60 genera of plants in North America, according to UConn Extension. Their preferred host is tree of heaven, an invasive tree, but they also feed on black walnut, butternut, maple, birch, sumac, willow and other trees.

Connecticut crops affected by the insect include apples, grapes, peaches, plums, cherries and apricots, according to UConn Extension.

What To Look For

Spotted lanternflies have one generation each year. They overwinter as eggs, which are laid in masses on trees and a wide variety of outdoor surfaces, including bricks, stones, vehicles and other objects.

The egg masses are about 1½ inches long and covered with a gray, mud-like coating. Each mass contains about 30-to-50 eggs.

The insects hatch in the spring and progress through four wingless nymphal stages. The first three stages are black with white spots. The fourth-stage nymphs develop a bright red body with black markings and white spots.

Adults begin appearing in July and remain active until killed by late-fall freezes. Adults are about 1 inch long, with spotted tan or gray forewings. Their hindwings, visible when the wings are opened, are red, black and white.

Why The Insect Is A Concern

Both nymphs and adults use piercing-sucking mouthparts to extract sap from plants. The insects excrete excess sugar as a sticky substance called honeydew, which can attract other insects and encourage the growth of sooty mold, according to UConn Extension.

Sooty mold can cover leaves, reducing photosynthesis, and can stain vehicles and outdoor structures beneath infested trees, according to UConn Extension.

Feeding also can damage branches. UConn Extension said spotted lanternfly feeding is particularly concerning for grapevines, where infestations have been associated with reduced yields and fruit quality. Heavy feeding can weaken grapevines, reduce their winter hardiness and potentially kill vines, according to UConn Extension.

Do They Bite?

Despite their sometimes intimidating appearance and ability to gather in large numbers, spotted lanternflies do not bite or sting people, according to UConn Extension. They can become a nuisance when present in large swarms, according to UConn Extension.

Residents Encouraged To Monitor Lanternflies

UConn Extension recommends monitoring plants and crops, particularly high-value plants and areas along field edges.

Residents should look for spotted lanternflies on tree of heaven, black walnut, maple, willow and birch. Circle traps and sticky bands can be used to monitor populations, although traps may also capture other species, according to UConn Extension.

Sightings can be reported to the Connecticut Agricultural Experiment Station.

Here is the link:

• survey123.arcgis.com/share/cd88aecff65948e795bac5f34e1b66d2

UConn Extension also recommends inspecting vehicles, agricultural products and equipment to help prevent the insect from being transported to new locations.

There currently is no coordinated public program to control spotted lanternflies in Connecticut, according to UConn Extension. Management options include removing preferred host plants, destroying egg masses by scraping or crushing them, and using traps.

In agricultural settings, insecticides can be used when populations reach unacceptable levels. UConn cautions that pesticide products must be used according to their labels and Connecticut regulations.

Some Facebook entomologists have recommended a home remedy — a dish soap and water concoction that reportedly disabled the bugs.

It's not so easy, UConn Extension says.

Said Kurtz, "Dish soap and water can be phytotoxic when sprayed on some plants and can be harmful to soil microorganisms. A better option is to use EPA approved insecticides according to label directions. "