The spotted lanternfly is established in Connecticut and poses a serious threat to the state’s agricultural industry, particularly grape and fruit production. The insect feeds on more than 70 plant species found across the state, and Connecticut officials actively track its spread through a public sighting-report system managed by the Connecticut Agricultural Experiment Station (CAES). If you live in Connecticut, here’s what you need to know about identifying, reporting, and managing this invasive pest on your property.
What the Spotted Lanternfly Does to Plants
Spotted lanternflies are sap feeders. Both nymphs and adults pierce plant tissue with needle-like mouthparts and drain sugary fluid from the vascular system. They don’t chew leaves or bore into wood. Instead, the damage comes from sheer volume: large groups feeding on the same plant weaken it over time, and the sticky waste they excrete, called honeydew, creates a cascade of secondary problems.
Honeydew coats leaves, fruit, and anything beneath an infested tree, including cars, decks, and patio furniture. It’s difficult to remove and attracts other insects. Worse, it promotes the growth of a black fungus called sooty mold, which blocks sunlight from reaching leaf surfaces and reduces photosynthesis. On fruit crops, sooty mold on the skin can destroy the entire harvest’s market value.
The Connecticut Department of Energy and Environmental Protection notes that spotted lanternfly has so far only killed sapling trees, sumac, grapevines, and tree-of-heaven during infestations. Mature hardwood trees typically survive, though they may show branch dieback and flagging. The picture is much worse for agriculture: heavy feeding on grapevines reduces yields, lowers fruit quality, weakens winter hardiness, and can kill the vine entirely. Connecticut’s apple, peach, plum, cherry, and apricot crops are also at risk.
Host Plants in Connecticut
The spotted lanternfly’s preferred host is tree-of-heaven (sometimes called stink tree), an invasive species already common along Connecticut roadsides, railroads, and disturbed areas. Adults concentrate their feeding on tree-of-heaven and grapevine starting in late July. But the insect’s full host list in Connecticut is remarkably broad: maple, oak, birch, walnut, willow, elm, beech, sycamore, tulip poplar, dogwood, sassafras, pine, ash, hickory, poplar, linden, hops, and serviceberry, among others.
If you have tree-of-heaven on or near your property, it serves as a magnet for spotted lanternfly populations. Some management strategies involve removing tree-of-heaven to reduce feeding sites, though this needs to be done carefully since cutting it down without treating the stump causes aggressive regrowth.
How to Identify Each Life Stage
Spotted lanternflies look different at each stage of their life cycle, which means people often encounter them without recognizing what they’re seeing.
- Egg masses (September through May): Grayish-brown, waxy clusters about an inch long, often described as looking like a smear of mud. Each mass contains 30 to 50 eggs. They’re laid on almost any flat surface: tree bark, outdoor furniture, vehicles, firewood, stone, and shipping containers.
- Early nymphs (spring): Small, black with white spots, roughly the size of a pencil eraser. They hop more than they fly and are easy to miss.
- Late nymphs (summer): Larger, with bright red patches and white spots. This is when most people first notice them.
- Adults (late July through fall): About an inch long with gray forewings covered in black spots. When they open their wings, you’ll see a flash of bright red on the hind wings. They’re strong jumpers and weak fliers.
Reporting Sightings in Connecticut
Connecticut asks residents to report spotted lanternfly sightings through the CAES online portal at portal.ct.gov. When submitting a report, you’ll need to enter your address and upload photos. Pictures are required because several native insects, including certain moths and beetles, are commonly confused with spotted lanternfly. You may not receive a personal response, but each report helps the state track the pest’s spread and allocate resources.
What You Can Do on Your Property
The most effective action homeowners can take is destroying egg masses between September and May, before they hatch. Use a plastic card, putty knife, or any flat, firm edge to scrape egg masses off surfaces and into a bag or container filled with rubbing alcohol or hand sanitizer. Leave the eggs submerged in the solution permanently. This step matters: egg masses scraped onto the ground without being destroyed can still hatch. You can also smash them in place, but apply firm, even pressure across the entire mass so every egg bursts.
With up to 50 eggs per mass, even removing a handful of clusters early in the season meaningfully reduces the local population. Check tree trunks, fence posts, firewood stacks, vehicles, campers, and any outdoor equipment that sits in one place for extended periods.
During the active season, circle traps (sometimes called funnel traps) wrapped around tree trunks can capture nymphs and adults as they climb. Older-style sticky bands work but have a significant downside: they trap birds, bats, and beneficial insects. If you use sticky bands, always cage them behind a wire mesh barrier so only small insects can reach the adhesive surface.
For properties with heavy infestations, particularly those with grapevines or fruit trees, targeted insecticide treatments applied to tree-of-heaven trunks can reduce adult populations. Contact your local UConn Extension office for guidance on timing and product selection specific to your situation and the plants you’re trying to protect.
Preventing Spread
Spotted lanternfly spreads primarily through human activity, not flight. Egg masses hitch rides on firewood, vehicles, trailers, outdoor equipment, and shipping materials. Before moving anything that has been stored outdoors, especially from an area with known infestations, inspect every surface for the mudlike egg masses. This is particularly important from fall through early spring when egg masses are present but easy to overlook.
Connecticut’s agricultural officials emphasize that preventing new introductions is far more effective than managing established populations. A single overlooked egg mass on a piece of patio furniture or a load of firewood can start an entirely new infestation miles from the nearest known colony.