Spotted Lanternfly in Nassau County: What Long Island Homeowners and Businesses Need to Know

Spotted Lanternfly Has Arrived on Long Island

The spotted lanternfly (Lycorma delicatula) — the invasive planthopper from Asia that devastated agricultural regions in Pennsylvania and New Jersey — has established itself in New York State, including Nassau County. This visually striking insect, with its distinctive red underwing and polka-dot outer wings, has moved steadily through the New York metro region and is now a confirmed presence across Long Island. For Nassau County homeowners, gardeners, and businesses with outdoor vegetation, understanding this pest and taking the right steps matters — both for your own property and for slowing a spread that has significant economic implications for the broader region.

What Is the Spotted Lanternfly and Why Does It Matter?

The spotted lanternfly (SLF) is not a fly despite its name — it's a planthopper that feeds on the sap of a wide range of trees, shrubs, and plants. Adults and nymphs pierce plant tissue and feed in large aggregations, excreting a sticky, sugary substance called honeydew that coats surfaces beneath infested trees and promotes the growth of black sooty mold. In large numbers, SLF feeding weakens trees, stresses grapevines and fruit trees, and makes outdoor living spaces unpleasant from honeydew accumulation.

SLF's preferred host plant is the tree of heaven (Ailanthus altissima), an invasive tree that grows prolifically throughout Nassau County — along railroad corridors, in disturbed areas, and at the edges of residential properties. However, SLF also feeds on maples, oaks, poplars, apple, cherry, peach, plum, hops, and many ornamental plants common in Long Island yards.

Spotted Lanternfly Life Cycle: What to Look For by Season

Egg Masses (October through May)

SLF overwinters as eggs laid in tan, mud-like masses on smooth surfaces — tree bark, fence posts, outdoor furniture, vehicles, and even stone walls. Each egg mass contains 30 to 50 eggs covered in a grayish waxy coating that blends with bark. In Nassau County, egg masses can appear on virtually any smooth outdoor surface from October through the following spring. Destroying egg masses before they hatch is the single highest-impact action homeowners can take — scrape them off and dispose of them in a sealed bag.

Nymphs (May through July)

Early instar nymphs are black with white spots and smaller than a pencil eraser. Later instar nymphs develop red patches. They are mobile and can jump significant distances. Nymphs begin feeding as soon as they hatch and move through vegetation throughout the spring and early summer.

Adults (July through December)

Adults emerge in late summer. At rest, they display their gray-spotted outer wings; when disturbed, they reveal the striking red underwing. Adults aggregate in large numbers on tree trunks in late summer and fall, feeding heavily before females lay egg masses. They die with the first hard frost, but their eggs survive winter to repeat the cycle.

What Nassau County Homeowners Should Do

Check Your Property and Report Sightings

New York State Department of Agriculture and Markets actively tracks SLF spread across Long Island. If you find spotted lanternfly on your Nassau County property — especially in an area where it hasn't previously been confirmed — report it at the New York State iMapInvasives platform or through the NYS DEC's pest reporting tools. Early detection in new areas helps pest management agencies respond more quickly.

Destroy Egg Masses

From October through April, inspect your property carefully for egg masses on tree trunks, fencing, outdoor furniture, vehicles, and any smooth outdoor surfaces. Scrape them off with a plastic card or putty knife into a container of hand sanitizer or rubbing alcohol to kill the eggs. Do not try to burn them — the eggs can survive briefly and the mass may not ignite cleanly.

Use Tree Banding with Caution

Sticky bands placed around tree trunks can trap SLF nymphs as they climb. However, these bands also trap songbirds, small mammals, and beneficial insects if used without protective wire caging. If you use sticky bands, follow New York State guidance by caging all banded trees with wire mesh that only insects can pass through.

Consider Removing Tree of Heaven

Tree of heaven (Ailanthus) on your Nassau County property serves as the primary SLF breeding and feeding reservoir. Removing it — ideally through a cut-stump treatment that prevents regrowth — reduces the SLF load on your property significantly. Note that simple cutting without stump treatment will cause Ailanthus to resprout aggressively. A licensed arborist or pest professional can handle this correctly.

Professional SLF Treatment for Nassau County Properties

Licensed pest control operators in New York can apply systemic insecticide treatments to high-value ornamental trees and landscape plants to protect them from SLF feeding damage. These treatments — applied as soil injections or trunk sprays — are absorbed by the plant and kill SLF as it feeds. They are particularly appropriate for mature trees, fruit trees, and valuable landscape specimens where significant feeding pressure has been observed.

Call (516) 517-9150 to discuss spotted lanternfly management options for your Nassau County property. We can assess your SLF exposure, identify tree of heaven on your property, and recommend appropriate control measures to protect your trees and outdoor living areas.