URBANA, Ill. — The invasive insect spotted lanternfly has been found in Illinois for the first time. Residents are being warned to watch out for and report sightings of this pest which can damage trees. Experts confirmed a population of the pests in Cook County on September 18 according to a September 27 Illinois Department of Agriculture media release.  

Spotted lanternfly (Lycorma delicatula) is a leafhopper native to eastern Asia that damages a wide range of fruit, ornamental, and woody trees by feeding on the sap. It could harm grape and logging industries but is not a threat to human or animal health. Like other invasive species, it can be hard to remove once populations are established, so prevention and early response is key to slowing the spread. 

Spotted lanternflies were detected in the U.S. in 2014 in Pennsylvania and have recently spread to the Midwest. Entomologist Kelly Estes says while this is the first known occurrence of the pest in Illinois, it’s not a reason to panic.  

“This invasive pest has been on our radar for quite some time, and we are continuing to learn more about how the spotted lanternfly behaves in the U.S.,” says Estes, University of Illinois Prairie Research Institute’s state Agriculture Pest Survey coordinator. “Recent research has shown that there are only a few plant hosts it may stay on for months and months causing more damage.” 

Feeding damage stresses trees and can weaken them. Young saplings and grape vines are more at risk from infestations than large trees. The insect’s waste product, called honeydew, also encourages the growth of mold that can harm the host plant.  

Illinois Extension Forestry and Research Specialist Christopher Evans says the pest can impact forest ecosystems to some degree, but the insect is more of a nuisance than a tree killer.  

“We are not going to experience waves of tree mortality like we saw with Emerald Ash Borer,” Evans says. “Instead, infestations can impact outdoor recreation through the mess they create through masses of insects on trees, production of sticky honeydew, and the sooty mold and other growths that feed on the honeydew.” 

Reports of spotted lanternfly sightings from the public will help researchers continue to monitor for populations. Send photos of spotted lanternflies to lanternfly@illinois.edu and include detailed information such as time, location, and number of insects. You can also contact the Illinois Department of Agriculture at (815) 787-5476 with any questions or concerns. University of Illinois Extension’s county offices are also able to help with identification and reporting. Connect with a local Extension office at go.illinois.edu/ExtensionOffice. 

After reporting sightings, remove and destroy spotted lanternflies by crushing nymphs and adults and scraping egg masses into a container with rubbing alcohol according to the IDOA.  

Adult spotted lanternflies are about one inch long. The front pair of wings are gray with black spots, and the tips of the front wings have speckled bands. The back pair of wings are red with black spots and a white band. Their heads and legs are black, and the abdomens are yellow with black bands. 

Spotted lanternflies are easiest to spot at dusk or at night as they move up and down the trunks of plants. During the day, they will often cluster near the base of the plant, making it hard to find them, according to the USDA.  

For more information and help with identification, download a factsheet, available in English at go.illinois.edu/SpottedLanternfly or in Spanish at go.illinois.edu/MoscaLinternaconManchas.  

Non-native invasive species are plants, animals, and insects that spread quickly, cause ecological or economic damage, and are hard to remove once established. Illinois' centralized location and extensive transportation networks provide many ways for pests to arrive. Across the state, Illinois Extension staff and volunteers work with communities to identify potential invasions, remove invasive species, and restore natural areas. Explore more about invasive species at go.illinois.edu/invasive.  

Sources: Kelly Estes, state agriculture pest survey coordinator; Christopher Evans, Extension forestry and research specialist; Ken Johnson, horticulture educator; Kacie Athey, assistant professor and Extension specialist; Nick Seiter, research assistant professor and faculty Extension specialist.  

Media inquiries: For media interviews with Extension experts, contact Bridget Lee-Calfas at bklee@illinois.edu and Dolan Klein at dolank@illinois.edu.  

Photo: Adult spotted lanternfly. By Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org