Spotted lanternfly

What is spotted lanternfly?

Spotted lanternfly is a sap-feeding planthopper native to Asia. APHIS says it was first found in Pennsylvania in 2014 and likely came in on goods shipped from overseas. It is a hitchhiker. Egg masses get laid on almost any hard surface, so trucks, trailers, stone, pallets and equipment can carry it to new places.

Nymphs and adults pierce the plant and drink sap. They give off sugary honeydew, and sooty mold grows on it. Penn State calls the insect a plant stressor. It is known to kill only grapevines, tree-of-heaven and young black walnut. On most yard trees the damage is a mess of honeydew and mold rather than a dead tree.

For contractors and landscapers the big issue is the quarantine. Waste, logs, stone, deck boards, mowers and other outdoor items moving out of a quarantined county can carry eggs. Pennsylvania requires businesses working in quarantined counties to hold a permit. See our spotted lanternfly in central PA article for local details.

People and pets: Penn State says spotted lanternfly cannot bite or sting.

More from us: Spotted lanternfly in central PA

Signs and damage

• Groups of nymphs or adults feeding on trunks and branches
• Sticky honeydew dripping onto leaves, decks, cars and patios below the tree
• Black sooty mold growing on the honeydew and on plants under the tree
• Gray, mud-like egg masses on bark, stone, outdoor gear and vehicles from fall to spring

Spotted lanternfly identification: what to look for

• Adult: About 1 inch long. Black abdomen with yellow bands. Gray front wings with black spots. Hind wings are red, black and white. At rest the wings are often closed, so you only see the gray spotted front wings.
• Larva: Nymphs have no wings and go through four stages. The first three are black with white spots. The fourth is red with white dots and black stripes, about 1/2 inch long.
• Eggs: About 30 to 50 eggs per mass, covered with a coating that looks like wet gray putty at first, then dries to a dull brown, dried-mud look.
• Damage: Honeydew and sooty mold on leaves and surfaces below. Heavy feeding can kill grapevines, tree-of-heaven and black walnut saplings.
• Timing: In PA eggs are laid September to December, hatch late April to June, and adults are out from July until hard freezes.

Life cycle

One generation a year in Pennsylvania. Eggs are laid from September to December and sit through winter. They hatch from late April into June. Nymphs go through four wingless stages, black with white spots first, then red. Adults show up in July and feed and lay eggs until hard freezes kill them.

When to look: Egg masses: from September (laying runs to December) until they hatch in late April to June. Nymphs: from hatch (late April to June) into summer. Adults: July until hard freezes.

Spotted lanternfly look-alikes

A few things get mixed up with it:

• Spongy moth egg mass (Lymantria dispar): Spongy moth egg masses are fuzzy, tan and felt-like. Lanternfly egg masses are gray-brown and look like smeared mud.

How to control spotted lanternfly

Cultural control

• Remove tree-of-heaven where you can; it is the favorite host. Penn State notes herbicide is usually needed to kill its roots, and keeping only male trees stops reseeding.
• Scrape egg masses you can reach into a bag or jar of rubbing alcohol or hand sanitizer, or smash them well. Don't climb trees or ladders for high ones.
• Use circle traps about four feet up smooth-barked trunks starting when nymphs hatch (late April to June).
• Skip sticky bands unless they have a wildlife guard such as fine window screen; chicken wire does not work. Check bands daily.

Biological control

• Penn State says no natural enemy is expected to bring US populations down much right now.
• Penn State does not currently recommend Beauveria bassiana products because results have been inconsistent.

Chemical control

Penn State lists two kinds of insecticides. Contact sprays kill on contact and wear off fast; named active ingredients include bifenthrin, beta-cyfluthrin, zeta-cypermethrin, carbaryl, malathion and natural pyrethrins, with lower-toxicity choices like insecticidal soap, horticultural oil and neem oil. Systemic products (dinotefuran, imidacloprid) are taken up by the tree and mainly hit adults; apply only after bloom to protect pollinators and only to actively growing trees, not in late fall or winter. Never spray blooming plants. Use only products labeled for this use; the label is the law. Penn State notes a certified pesticide applicator can do the work. Muthler Landscaping does not spray or treat trees. For trees, call an ISA Certified Arborist; for pesticides, use a licensed applicator (see our pesticide applicator license guide).

Use only products labeled for this pest and this site; the label is the law. For trees, work with an ISA Certified Arborist. If you hire someone to apply pesticides, make sure they hold your state’s pesticide applicator license; the rules for each state are in our pesticide applicator license guide.

Prevention

• Check vehicles, trailers and equipment before leaving a job site, including wheel wells, bumpers, grills and roofs.
• Inspect stone, pavers, pallets, deck boards and outdoor gear for egg masses before moving them out of a quarantined county.
• Keep windows closed and avoid parking under infested trees.
• Don't move firewood; see our firewood rules guide.
• Check outdoor items for egg masses before you bring them inside for winter.

When to call a pro

Call an ISA Certified Arborist if large or valuable trees, especially maples, walnuts or willows, are covered with lanternflies, or if you are thinking about systemic treatment. Pesticide work for hire needs a licensed applicator.

Related guides: Tree database: mature size and planting distance · Pennsylvania tree identification · Firewood rules by state · All pests and diseases

Questions about spotted lanternfly

Similar pests and diseases