The spotted lanternfly is now established in all five Rhode Island counties. First detected as a single insect in Warwick in 2021, the invasive pest spread quickly, with the state’s first confirmed breeding population discovered along Route 7 in Smithfield in 2022. Rhode Island residents should know how to identify it at every life stage, report sightings, and take practical steps to reduce populations on their own property.
How the Spotted Lanternfly Reached Rhode Island
Originally from China, the spotted lanternfly was first detected in the United States in Pennsylvania in 2014. It spread outward from there, hitching rides on vehicles, shipping containers, and outdoor equipment. Rhode Island’s first confirmed finding came in 2021: a single adult spotted in an industrial and commercial area in Warwick near Jefferson Boulevard. That lone insect raised alarms but didn’t yet prove a breeding population existed in the state.
That changed in August 2022, when the Rhode Island Department of Environmental Management (DEM) investigated a credible report in Smithfield and found patches of lanternflies along Route 7. The USDA confirmed this as Rhode Island’s first established population. Since then, the insect has spread to every county. Providence and Kent counties have seen the heaviest establishment, but no part of the state is unaffected.
How to Identify Spotted Lanternflies
There is one generation per year. Adults die off in winter, but their eggs survive the cold and hatch in spring. Knowing what each stage looks like helps you catch infestations early.
- Egg masses (September through May): About one inch long, laid on hard surfaces like tree trunks, stones, patio furniture, and vehicles. Fresh egg masses look like a smear of white putty. As they age, the coating cracks and turns mud-colored. Underneath, you can see individual seed-like eggs.
- Early nymphs (spring): Tiny black insects covered in bright white spots, growing to about a quarter inch long. They’re strong jumpers and will leap away when disturbed.
- Late nymphs (summer): About half an inch long, bright red with black stripes and white spots. Still strong jumpers.
- Adults (late summer through fall): About one inch long, with gray forewings dotted in black spots. When they open their wings, a flash of bright red is visible on the hind wings. Females tend to be slightly larger than males.
Why They’re a Problem
Spotted lanternflies feed by piercing plant tissue and sucking out sap. They target over 70 plant species, including grapevines, fruit trees, maples, oaks, and willows. For Rhode Island’s vineyards and orchards, this is a direct economic threat. Heavy feeding weakens and can kill grapevines in particular, making the pest a serious concern for the state’s wine industry.
As they feed, lanternflies excrete a sticky substance called honeydew that coats surfaces beneath them. This honeydew promotes the growth of sooty mold, a black fungus that covers leaves, decks, cars, and outdoor furniture. The mold blocks sunlight from reaching leaves, further stressing plants. Even if you don’t grow crops, large populations on your property can coat patios, driveways, and vehicles in a sticky, moldy mess.
The Tree of Heaven Connection
The spotted lanternfly’s preferred host is the tree of heaven, another invasive species from Asia that grows aggressively throughout Rhode Island, especially along roadsides, railroads, and disturbed areas. This fast-growing tree produces a readily available food source that helps lanternfly populations multiply and expand their range. If you have tree of heaven on your property, it is likely attracting lanternflies.
Simply cutting down tree of heaven backfires. The tree responds by sending up vigorous sprouts from its stump and root system, potentially creating an even larger problem. The more effective approach is what’s called the trap tree method: remove most of the tree of heaven in an area but leave a few standing. Those remaining trees draw lanternflies to a concentrated location where they can be targeted with sticky bands or other controls. Proper removal of the extra trees requires treating cut stumps to prevent regrowth.
What You Can Do on Your Property
The most effective action for homeowners is destroying egg masses between September and May, before the next generation hatches. Scrape egg masses off surfaces using a plastic card or putty knife, and drop them into a container filled with rubbing alcohol or hand sanitizer. Leave them in the solution permanently. This step matters because egg masses scraped onto the ground can still hatch.
You can also smash egg masses in place, but you need to apply firm, even pressure across the entire mass. A properly crushed egg will burst open. If eggs are out of reach on high branches, don’t climb a ladder to get them. Instead, horticultural oils sprayed directly onto egg masses can kill up to 75 percent of treated eggs when applied at a concentration of at least 3 percent. Mineral and paraffinic oils are the most effective options. Soybean oil also works but requires a much higher concentration (around 50 percent) to achieve similar results. The key is thorough coverage directly on the egg mass.
For nymphs and adults found on your property, stomping them is straightforward and encouraged. Sticky tree bands can catch nymphs as they climb, though these should be used carefully to avoid trapping birds and other wildlife. Wrapping bands with wire mesh or chicken wire helps reduce bycatch while still trapping lanternflies.
How to Report Sightings
Even though the spotted lanternfly is now established statewide, the Rhode Island DEM still tracks sightings to monitor population density and spread. If you spot lanternflies or egg masses, especially in areas where they haven’t been reported before, report them to the DEM through their agriculture division. Take clear photos showing the insect or egg mass, ideally with something nearby for scale, and note the exact location. Reports help the state prioritize management efforts and track how quickly populations are growing in different areas.
Checking Vehicles and Outdoor Items
One of the main ways spotted lanternflies colonize new areas is by laying eggs on vehicles, trailers, camping gear, firewood, and other items that get transported between locations. Before moving anything that’s been parked or stored outdoors, check it for egg masses. They can look remarkably like a dried smear of mud, so inspect closely. This is especially important if you’re traveling to or from states with heavy infestations like Pennsylvania, New Jersey, or Connecticut. A single overlooked egg mass, containing 30 to 50 eggs, can seed a new population wherever it ends up.