Invasive noticed lanternfly anticipated to reach in Wisconsin, insect skilled says

A new invasive insect is making its way statewide toward Wisconsin, with one expert saying it’s only a matter of time before it hits the state.

Native to China, the spotted lanternfly first appeared in Pennsylvania in 2014. Since then, it has been found in 12 states. The US Department of Agriculture says the species “could seriously affect the country’s grape, orchard and lumber industries” if it continues to spread.

Economists from Penn State’s College of Agricultural Sciences estimate that the spotted lanternfly could cost their state’s economy at least $324 million annually and about 2,800 jobs.

PJ Liesch, manager of the University of Wisconsin-Madison’s Insect Diagnostic Lab, recently took part in Wisconsin Public Radio’s “The Larry Meiller Show” to talk about the insect and its potential impact on the state.

The spotted lanternfly is like a giant aphid in that it has a needle-like mouth that can drink from plants, he said. Hundreds or thousands of them can feed on trees or vines, and all the drinking harms the plants.

Liesch said feeding them can lead to a “pretty messy situation all around” because they’re excreting honeydew, which is excess sugar in their waste. Mold can also grow on it.

The spotted lanternfly feeds on a wide variety of plants, Liesch said. Experts have documented at least 70 plant species. He said he hadn’t heard as many concerns about crops or vegetables. Usually they hunt trees.

“Think of Door County cherry trees and apple orchards,” he said. “We know that fruit trees can be endangered. But an even bigger concern for us at the bigger picture level is grapes. This insect really, really loves grapes. So, wine growers and the wine industry here in the state and in the Midwest will likely have to deal with this insect in the not too distant future.”

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Liesch said these insects are great hitchhikers. They can find their way on cargo shipped from the east coast. He said the spotted lanternfly resembles the spongy moth in how it can lay eggs on non-vegetable material, like the underside of a vehicle or a truck loaded with pallets.

There have been a small number of cases where dead spotted lanternflies have been found in goods shipped to Wisconsin, he said, recalling one time last year when one was found dead in a southern Wisconsin warehouse after she had come from southeastern Pennsylvania.

So what should happen if – or when – they make it to Wisconsin?

Some states with the bugs are encouraging residents to kill the bugs, sometimes by holding events or developing an app to track kills, the New York Times recently reported. These calls are rejected for reasons such as animal rights or how harmful the flies can be.

Liesch said managers of Wisconsin vineyards may need to spray a lot of insecticides. But he said the spotted lanternfly is quite mobile, making it difficult to stop.

Another method is sticky tapes wrapped around tree trunks to prevent the insects from running up the tree. However, Liesch said there were concerns the tapes could affect birds and squirrels.

“It’s definitely a difficult pest to deal with,” he said.