Invasive pest experts believe spotted lanternflies are one of the most serious insect threats ever faced in the United States. Since their 2014 detection in Pennsylvania, these native Southeast Asian pests have spread steadily into nearby states. Hidden in shipments from the Northeast, they've even been intercepted on the West Coast.
Most U.S. states are now considered at risk for potential infestations of these devastating insects. By learning how to identify and control spotted lanternflies, you can help protect against their spread:
Despite the moth-like appearance of spotted lanternfly adults, these damaging planthopper pests are true bugs. Their offspring hatch as nymphs, not larvae. Their distinctive appearance simplifies identification at every life stage. Spotted lanternflies overwinter as eggs, which hatch into baby spotted lanternflies in spring. The nymphs molt and progress through four stages, called instars, and grow more destructive as they mature.
Spotted lanternfly egg masses look like lichens or dried mud.
Spotted lanternfly eggs first appear in fall when mated adults lay egg masses. Found on nearly any hard surface — from patio furniture and car grills to tree trunks — the waxy, one-inch egg masses look like putty when fresh and cracked mud when dried. Each mass contains up to 60 eggs, laid vertically in several columns.1
Young, black-stage spotted lanternfly nymphs have a polka-dot appearance.
Black-stage nymphs make up the first three instars, from spring hatching through the third, midsummer molt. Early stage spotted lanternfly nymphs grow up to 1/4 inch long. Bright white spots dot their wingless black bodies and legs.
Red-stage nymphs can pierce bark and damage trees.
Red-stage nymphs represent the spotted lanternfly's final instar. Appearing in midsummer through autumn, these juvenile spotted lanternflies grow up to 3/4 inch long. Their white-spotted black bodies develop bright red coloration.
When disturbed, adults spread their wings to show patches of red.
Adult spotted lanternflies usually appear with their wings folded like tents above their backs. At rest, these pests measure about 1 inch long and 1/2 inch wide. Adults appear and feed from midsummer until a killing frost in fall. Their pinkish forewings — spotted with black — have a brick-like pattern toward their tips. The seldom-seen black-and-white hindwings have bright red patches with black spots. When extended, the colorful wings span 2 inches.
Spotted lanternflies damage plants and property at all life stages. These pests have mouthparts that pierce plant tissue and suck vital juices from their target plants. Black-stage nymphs are unable to penetrate woody plants and tree bark. These juvenile spotted lanternflies damage annuals, perennials and tender, new plant growth instead. Red-stage nymphs and adult spotted lanternflies can pierce woody bark; these stages focus on trees.
The Tree of Heaven, known by the scientific name Ailanthus altissima, is the spotted lanternfly's preferred host plant. Found throughout the United States, this invasive Asian tree directly supports the pest's spread in the U.S. and abroad. But spotted lanternflies adapt quickly. Their U.S. diet encompasses more than 100 plant species, including grapevines; fruit trees from apples to peaches; blueberries; maple trees; walnut trees; birch and pine.2
Spotted lanternflies are swarm feeders that gather in large groups to feed in early evening. Unmistakable mobs of thousands of adults may converge on a single tree trunk, consuming significant amounts of tree sap. Damaged trees continue to weep sap after the attack. Weakened trees and plants fail to thrive or produce fruit and often die. In some areas, infestations have devastated important agricultural crops and ornamental plants.
Large quantities of honeydew, which is excreted by spotted lanternflies as they feed, is an unpleasant byproduct of lanternfly infestations. The sticky substance accumulates, along with oozing sap, around the bases of trees. It also blankets sidewalks, patios, furniture, cars and any other objects below. The pooling honeydew attracts wasps, ants and other pests, then develops a whitish fungus that ripens into black sooty mold.
The invasive Tree of Heaven attracts masses of spotted lanternflies.
Because spotted lanternflies are not native to North America, natural predators aren't present to limit these pests. Taking steps to kill, control and prevent these invasive pests is critical to protect your property and help stop the spotted lanternfly's spread. If you have Tree of Heaven on your property, consider removing this invasive plant before it attracts spotted lanternflies.
Effective control of spotted lanternfly nymphs and adults targets these pests at all life stages. Inspect your property thoroughly for egg masses in fall and winter. Scrape the masses from their surfaces and destroy the eggs to prevent spotted lanternfly nymphs in spring. If you have known infestations in your area, be proactive with preventative treatments to protect against these pests.
Treat landscape plants, shrubs and trees with Amdro Quick Kill Outdoor Insect Killer Ready to Spray or Amdro Quick Kill Outdoor Insect Killer Concentrate to control spotted lanternfly nymphs and adults, These highly effective residual insecticides work in minutes to kill existing spotted lanternflies by contact. Then they keep protecting treated plants and trees against new spotted lanternflies for up to three months. You can even treat your home's foundation up to a height of 3 feet.
When treating, give extra attention to tree trunks where these pests gather. Spotted lanternfly nymphs are strong jumpers. Though early black-stage nymphs don't pierce tree bark, they often move up and down tree trunks near the ground. Late red-stage nymphs and adults gather in those same areas, so targeted treatment maximizes results. Adults feed for about one month in late summer and fall before laying eggs. Treating during this crucial time when adults are visible prevents egg masses and future generations.
If you see spotted lanternflies in your area, report the sighting to your local county extension office or your state department of agriculture immediately. With the help of Amdro brand, you can protect your plants and property against spotted lanternfly damage and help stop the spread of these destructive pests.
Always read product labels and follow the instructions carefully.
1. New York State Integrated Pest Management, "Spotted Lanternfly IPM," Cornell University.
2. T. Simisky, "Spotted Lanternfly," University of Massachusetts Amherst.