The spotted lanternfly (Lycorma delicatula) or SLF, is an invasive insect from Asia that threatens a wide variety of plants such as hops, grapevine, walnut, fruit trees, maple trees. Its preferred host is an invasive plant called the tree of heaven (Ailantus altissima).
SLF was likely introduced to the United States as egg masses transported on a stone shipment from China, India, Vietnam or South Korea. The first US infestation was discovered in 2014, in Berks County , Pennsylvania and has since spread to other parts of PA in addition to bordering states. View a Map of SLF Distribution.
Spotted lanternfly can devastate New York’s agricultural and tourism industry and threatens our forests. It feeds on over 70 different plant species including, grapevines, hops, fruit and nut trees, and maple trees. SLF feeds in large numbers and excretes honeydew that attracts sooty molds; these molds interfere with plant photosynthesis and impact crop growth and yields. The honeydew impedes tourism as it puts off a foul odor and attracts stinging insects.
Signs of infestation
Sap oozing or weeping from wounds on host plants that appear wet and may give off a fermented odor. The presence of egg masses that are one-inch-long and appear to be brownish-gray and waxy or are brown and scaly.
Early-stage SLF nymphs are black with white spots, they range in size depending on their life-cycle stage. SLF turn red with white spots just before they transform into winged adults. Adults are 1 inch long and ½ inch wide with greyish colored forewings and red hindwings with black spots, their upper wing portions are dark with white stripes. Adult SLF usually appear in July. In the fall, SLF adults lay egg masses that are an inch long with a smooth brownish-gray waxy appearance, as the egg masses age they turn brown and scaly.
The best mode of control for SLF is prevention. SLF easily spreads by hitchhiking to new areas on vehicles, firewood, outdoor furniture, stone, etc. Be sure to check your vehicles and gear when traveling from or stopping within known quarantine areas (NY, PA, NY, DE, MD, and VA). Monitor tree of heaven populations for signs of SLF.
Monitor tree of heaven, young black walnut, wild grapevines and other SLF host plants for signs of infestation. Use a plastic card or putty knife to scrape egg masses into a container filled with rubbing alcohol or hand sanitizer to collect a specimen for confirmation. Banding trees with specifically designed bug bands helps catch nymphs and adult SLF and reduces by-catch. Recent research indicates the removal of Tree of heaven increases SLF dispersal, as they seek suitable hosts further away.
There are pesticides labeled for specific crops and application restrictions for spotted lanternfly in New York State. For regulations and guidance for controlling spotted lanternfly with pesticides reach out to the NYS Integrated Pest Management out of Cornell University at firstname.lastname@example.org.