Spotted Lanternfly

Lycorma delicatula

Identify Report News Factsheets

What is the Spotted Lanternfly?

The spotted lanternfly Lycorma delicatula, (SLF) was first found in North America in Pennsylvania in late 2014. It is an exotic, invasive sap-feeding planthopper that has the potential to severely impact Connecticut’s agricultural crops, particularly apples, grapes, and hops, and ornamental trees. Spotted lanternfly adults feed on more than 70 species of plants. Its preferred host tree-of-heaven (Ailanthus altissima) is highly invasive and is abundant along highways, in urban areas, and along the edges of agricultural and industrial areas, where the spotted lanternfly could easily become established.

Why is it so important to stop an SLF invasion?

Approximately half of Connecticut's trees are threatened by spotted lanternfly invasion according to data from Connecticut's Department of Energy and Environmental Protection (DEEP). As spotted lanternfly nymphs and adults feed on the sap from trees and vines, the entire plant can become weakened because it cannot conduct photosynthesis as effectively. The excretions from these leaf-hopping insects encourage the growth of black sooty mold, thereby reducing photosynthesis. Agricultural crops will have reduced yields due to SLF feeding on fruit and generally weakening plants, if not completely destroying them (DEEP, 2020).

What should citizens do if they see a spotted lanternfly?

The public is urged to report potential sightings of this invasive pest. If you suspect you have found a SLF, snap a picture of it and fill out our reporting form by clicking this link: SLF Reporting Form. If you have other questions or comments please email ReportSLF@ct.gov. Please include in your email your contact information, any photos, and any other pertinent information. Permission by residents and businesses for state and federal plant inspectors to examine host trees on private property will be helpful in determining the extent of the infestation. All reports are confidential.

How to identify SLF

Adult spotted lanternflies are about one inch long and one half inch wide. Tan forewings that have black spots, while their signature colorful hindwings have lower red patches and upper black patches, separated with a white section in between. The red hindwings are mostly hidden unless the wings are spread. Adult SLF crawl, jump, or fly short distances. You will see adults from July to November.

Fig 1: Side view of adult SLF

Emelie Swackhamer, Penn State University, Bugwood.org

Fig 2: Top view of SLF adults with wings open and closed

Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org

Spotted lanternfly eggs hatch in the spring and early summer. Early instar nymphs are black in color with white spots; fourth instars nymphs are red with black and white spots. You will see nymphs from April to October.

Fig 3: Early stage nymph

Lawrence Barringer, PDA, Bugwood.org

Third instar SLF nymph

Fig 4: Late stage nymph

Victoria Smith, CAES

Fig 5: SLF adults and late stage nymphs

Richard Gardner, Bugwood.org

Fig 6: Early and late stage nymphs

Victoria Smith, CAES

The spotted lanternfly eggs masses are laid on practically any surface including trees, stones, trash cans, side of a house, etc. during the fall. Egg masses are yellowish-brown in color, and most are covered with a gray, waxy coating prior to hatching (USDA, 2019). They may appear wet or sticky when fresh. You will see eggs from September to May.

Fig 7: Fresh egg mass

Emelie Swackhamer, Penn State University, Bugwood.org

Fig 8: Old egg mass

Lawrence Barringer, PDA, Bugwood.org

Fig 9: SLF adult and egg masses

Richard Gardner, Bugwood.org

Fig 10: SLF egg masses

Lawrence Barringer, PDA, Bugwood.org

Where is SLF found?

While tree-of-heaven, Ailanthus altissima, is a favored host tree, spotted lanternfly may be found on other trees including maple, walnut, and willow. It feeds on agricultural crops like apples, grapes, hops, as well as other fruit trees. It is native to China, India, and Vietnam. The adults tend to congregate on the tree-of-heaven and other host trees in the fall.

To identify Ailanthus altissima: click this link to view the tree-of-heaven identification fact sheet

Please check your vehicles for stowaways! Inspect your vehicles, trailers, and other items for SLF adults and egg masses when travelling through areas with known or suspected SLF populations. These insects are known to hitch a ride on vehicles and even clothing. Jump to: where SLF has been seen.

What will life be like when the spotted lanternfly comes to CT?

Spotted lanternfly is probably the most serious agricultural pest to hit US shores in a long time. The insect can kill a vineyard in a year or two. The SLF has real potential to become a “quality of life” pest. Spotted lanternfly is a sap-feeding planthopper that produces large amounts of liquid excrement called honeydew. In addition, the feeding of this insect also causes trees to weep sap, which combined with excreted honeydew creates conditions for sooty mold to grow. In infested areas, honeydew may rain down on surfaces, vehicles, and people, creating unpleasant situations. The honeydew is slippery on surfaces, and there have been reports of broken bones due to people falling down slick steps or slippery decks. The honeydew also may attract stinging bees or wasps. Often trees affected by SLF also have a fermented odor. In addition, other countries may refuse to accept US agricultural exports, if they feel that they may be contaminated with SLF.

Fig 11: Weeping sap from SLF feeding

Gerda Magana, CAES

Fig 12: SLF feeding damage

Emelie Swackhamer, Penn State University, Bugwood.org

A backyard tree infested with many SLF

Fig. 13: A backyard tree infested with SLF

Lawrence Barringer, PDA, Bugwood.org

Fig. 14 Sooty mold

Kenneth R. Law, USDA APHIS PPQ, Bugwood.org

Where has the SLF been seen?

Since first reported in 2014, spotted lanternfly has spread to multiple states, and interceptions of single adults have occurred throughout the northeast, including in Connecticut, in 2018 and 2019. In 2020, two small established populations of spotted lanternfly were found in Fairfield county in Connecticut. SLF has also been reported in New York, New Jersey, Delaware, Maryland, Virginia, and West Virginia.

To see a map of SLF sightings on Cornell CALS's page, click this link: Map of Confirmed SLF Sightings

To see the latest SLF sightings, check out The CAES's press releases by clicking this link: Press Releases