Spotted Lanternfly Spreading in the Northeast: What You Need to Know

Spotted Lanternfly: A Growing Crisis in the Northeast

The spotted lanternfly (Lycorma delicatula) has become one of the most talked-about invasive pests in the United States. First detected in Berks County, Pennsylvania in 2014, this planthopper from Asia has since spread aggressively across the Northeast, establishing populations in Pennsylvania, New Jersey, New York, Connecticut, and Delaware. Its ability to feed on more than 70 plant species makes it a serious threat to agriculture, forestry, and residential landscapes.

Unlike many tree pests that target a single host, the spotted lanternfly is a generalist feeder. While it strongly prefers the tree of heaven (Ailanthus altissima), it also feeds heavily on grapevines, maples, oaks, willows, birches, and fruit trees. This wide host range means virtually every property in the affected region is at risk.

How to Identify Spotted Lanternfly

Use our tree identification tool to confirm host trees on your property, then watch for these signs:

• Adult insects (about 1 inch long) with gray forewings dotted with black spots and bright red hindwings
• Egg masses that look like smears of gray mud on tree trunks, rocks, and outdoor furniture
• Nymphs that are black with white spots (early stage) or red with white spots (late stage)
• Honeydew buildup — a sticky, sugary substance coating leaves, branches, and surfaces below infested trees
• Sooty mold — a black fungal growth that develops on honeydew-coated surfaces

Why Spotted Lanternfly Is So Damaging

Spotted lanternflies feed by piercing bark and stems with their needle-like mouthparts and sucking sap. Large populations can weaken trees significantly, leaving them vulnerable to secondary infections and winter stress. The honeydew they excrete promotes sooty mold growth, which blocks sunlight from reaching leaves.

For the wine and grape industry in Pennsylvania and New York, the economic threat is enormous. Infested vineyards have reported vine death within just two years. The USDA estimates potential annual losses exceeding $300 million in the grape, apple, and hardwood industries across the affected states.

Current Spread and Quarantine Zones

As of early 2026, quarantine zones have been established across large portions of the Northeast:

• Pennsylvania — All 67 counties are under quarantine
• New Jersey — Statewide quarantine in effect
• New York — Multiple counties in the Hudson Valley, New York City boroughs, and Long Island
• Connecticut — Expanding detections in Fairfield and New Haven counties
• Delaware — Established populations in New Castle and Kent counties

Check your state guide for the latest quarantine maps and local reporting requirements.

What Homeowners Can Do

Taking action on your own property makes a real difference:

• Scrape egg masses into a bag of rubbing alcohol or hand sanitizer from September through May
• Use circle traps or sticky bands wrapped around tree trunks to capture nymphs and adults
• Remove tree of heaven from your property to reduce the preferred host — but treat stumps with herbicide, as cut trees resprout aggressively
• Report sightings outside known quarantine zones to your state department of agriculture
• Inspect vehicles and outdoor items before traveling out of quarantine zones

Contact an ISA Certified Arborist for professional treatment options, including systemic insecticides that protect high-value trees. You can also diagnose symptoms of pest damage on your trees using our online tool.

Frequently Asked Questions

Q: Can spotted lanternfly kill my trees? A: While spotted lanternfly rarely kills healthy mature hardwoods outright, heavy feeding over multiple seasons can severely weaken trees, making them susceptible to other stresses and secondary pests. Young trees, fruit trees, and grapevines are at higher risk of death.

Q: Is it legal to transport firewood out of a spotted lanternfly quarantine zone? A: Most quarantine orders restrict the movement of firewood, outdoor furniture, and other items that could harbor egg masses. Violating quarantine can result in fines. Always check your state regulations before moving materials.

Q: Do spotted lanternflies bite or sting? A: No. Spotted lanternflies do not bite, sting, or pose any direct threat to humans or pets. The damage is entirely to plants and trees.

Q: When is the best time to treat for spotted lanternfly? A: Egg mass removal is effective from fall through early spring. Sticky traps work best from May through August when nymphs are active. Systemic insecticide treatments are typically applied in spring before populations build.