Invasive spotted lanternflies are native to China and can cause serious damage to apple trees, grapevines, hops, and other crops. Michigan State University’s Extension has been educating growers and nurseries about the lanternflies for the last two or three years.
Deb McCullough is a professor in forest entomology at MSU who works with Michigan State University Extension. She said news coverage has been overblown.
“My personal feeling is we need to tone down the rhetoric. These are not insects that kill trees, they haven't even killed grapevines.”
Spotted lanternflies don’t sting, they don’t bite, and they aren’t harmful to pets or humans. But a large infestation, like what’s happening now in New York and New Jersey, can be destructive to vineyards and fruit crops. Even if it’s not harmful to humans, it is aggravating and sticky too. Sticky because spotted lanternflies excrete a stinky, sticky substance called “honeydew.”
“It's going to be annoying,” said McCullough. “There's times when there's just hundreds of these insects on an individual tree, squirting honeydew and then you get black sooty mold and wasps want to come feed on the honeydew and you know there's some days where it's just going to be really annoying. But these are not tree killing insects. I think we can manage them, I think we can live with them. You know, if the people in New Jersey can deal with them. I'm real confident people in Michigan can deal with them.”
Since it was reported in Oakland County earlier this month there have been several reported sightings in other parts of the state that turned out to be false. If you think you’ve found one, McCullough said try to capture it.
“If you can collect a specimen, that would be great, you know, a plastic bag or a little jar, anything like that. Peanut butter jar, whatever it takes, that would be great. Just be sure you make note of the address where you are,” McCullough said, and then report the sighting to the Michigan Department of Natural Resources “Eyes in the Field” website.
McCullough said it’s going to take some time for the colorful insect to migrate to Southwest Michigan. Adult lanternflies often hitch a ride on a truck, train or car.
“My expectation is that we will have a couple of years before the populations really get big and reach that density where they're just super annoying to people in the area.”
When that happens, she said targeted insecticides work. In the meantime, if you’ve got tree-of-heaven on your property pull it out. It’s an invasive, non-native species from China and a favorite host plant spotted lanternflies love. By removing tree-of-heaven, McCullough said it will help mitigate an infestation.
“Cut them down. I don't think anybody would lose any sleep about having tree-of-heaven be removed,” McCullough said. “I will say if you're going to cut it down, you have to treat the stump with a herbicide because otherwise it will sprout and you know, one big tree will turn into 15 or so little trees.”
But before you start cutting anything down, McCullough said make sure you’re removing the right thing. Tree-of-heaven leaves look a lot like sumac or black walnut. Both are beneficial, native plants that should not be cut down. Go to the MSU Extension website or call the Kalamazoo Extension office for guidance at 269-383-8830 before cutting down something you suspect is tree-of-heaven.
