'Most Unwanted' Lanternfly Hasn't Arrived In IL, But Could Surface

ILLINOIS — A one-inch spotted insect may not seem like a huge reason for concern, but has found its way onto Illinois’ Most Unwanted List and should be killed on sight if seen, experts say.

The spotted lanternfly has not been spotted in the state so far, but the colorful winged creature could take up residence in Illinois, experts from the University of Illinois say. Much of the state is conducive to the spotted lanternfly, which has not only landed on the list of the Most Unwanted species in Illinois, but is also a federally regulated invasive pest, experts warn.

That’s why Department of Agriculture officials ask that these insects be killed on sight if found, due to the harm they can do to plants if left to their own devices. Both nymphs (younger species) and adults suck sap from stems, branches, and tree trunks, according to University of Illinois Extension Office experts.

“When large numbers of these insects start feeding on plants, it can reduce the vigor of the plants,” University of Illinois extension specialist Ken Johnson wrote on the office's website. “Their feeding can also cause dieback on branches. The damage they cause while feeding (they have a piercing-sucking mouthpart) also creates an opening for pathogens to get into plants and cause disease.”

The spotted lanternfly is native to China, India and Vietnam, and first made its way to the United States in 2012, officials. The unwanted visitors made their way here in a shipment of stone but weren’t detected in the U.S. until 2014, when they were first seen in Berks County, Pennsylvania.

Since then, they have been found in eight other states — as close as Ohio and southern Indiana — and although they have not yet been found in Illinois, the state presents a highly suitable environment for these insects, experts say.

One generation of the spotted lanternfly is seen once each year and is usually most detected around July. The adults can often be found in large groups on the tree of heaven, an invasive tree species native to China, as well as grapes, but will disperse when it comes time to lay eggs.

Female species will begin to lay eggs in September and can continue laying them until late November or early December, according to extension office experts. They will lay masses of 30- 50 eggs on various surfaces such as tree bark, stones, metal, and outdoor furniture and then cover them with a gray, waxy coating. It is believed that each female will lay at least two of these masses. As time goes on, the waxy coating may begin to crack and look like dried mud. The eggs will then start to hatch in May.

The adult spotted lanternfly grows to about an inch long and has gray front wings with black spots, and the tips of the 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 their abdomens are yellow with black bands.

If spotted, Johnson — the University of Illinois expert — asks that residents send a photo and a detailed email to lanternfly@illinois.edu and include where, when, and the specifics of the location. Residents also should contact the Illinois Department of Agriculture at 815-787-5476.