PHILADELPHIA (KYW Newsradio) — A new study by Penn State University suggests those pesky spotted lanternflies may not be as terrible for vegetation as scientists once believed.
For the last four years, entomology professor Dr. Kelli Hoover and her team have studied the effects spotted lanternflies have on trees.
“We released a certain number of lanternflies at the beginning of each season and then we proceeded to count how many were on this tree versus that tree,” she explained.
In the second year, she said they started to see a decline in photosynthesis and in the storage of starch in their roots. Over time, though, almost all of the trees fully recovered.
“The silver maple, the willow, the river birch — except tree of heaven,” she said.
While the tree of heaven — which, like the spotted lanternfly, is an invasive species from China — saw the worst effects, it did not die. Its growth was only slowed down.
Hoover noted that the insect did have a tendency to stay on the tree of heaven longer than other trees. And, her team kept the trees under duress of the insects for a longer period than what they would normally experience in the wild, so these results bode better overall.
“Given that we used the worst-case scenario in order to see effects suggests that in nature there won’t be nearly as big effects as we saw,” she explained. “We have seen spotted lanternfly kill even large, established tree of heaven, some red maples and some black walnut saplings, but that’s rare.
“The worst-case scenario is still not that terrible, but if I had a nursery and I was growing trees to sell and I needed to get them to a saleable size, I would treat for lanternfly infestation to prevent growth from declining.”