Our next ‘plague’ in western Pennsylvania – the spotted lanternfly
Although I have been reading about the Asian pest for several years, I saw my first spotted lanternfly last week when I visited Lancaster County, Pennsylvania. Within minutes, I had also seen my second, third, fourth … and 20th lanternflies. I stopped at my son’s house in Elizabethtown later in the day, and he showed me many more.
At Chickies Rock County Park, I talked with a Lancaster County park ranger, who told of scraping and destroying hundreds of lanternfly egg masses from trees last winter. He also advised that I check my pickup before leaving because lanternflies are excellent hitchhikers. Sure enough, I found and dispatched several adult spotted lanternflies clinging to the outside.
Last March, the Pennsylvania Department of Agriculture expanded the spotted lanternfly quarantine from 14 to 26 counties – including Blair, Huntingdon and Mifflin. These three counties form the southern border of Centre County — where I live. I hope not, but quite possibly I will see the pests in my backyard as early as next summer.
Spotted lanternflies were first discovered in Pennsylvania in Berks County in 2014 and are currently found in about one third of Pennsylvania counties — predominantly in the southeast. They are spreading in every direction.
There is one generation per year. Eggs are laid in the fall and hatch in the spring. Each egg mass has 30-50 eggs. During the late spring and early summer, they are tiny and go through four nymphal stages. Adults, the ones that I saw in Lancaster County, emerge in July and can be active until winter sets in.
Spotted lanternflies do not usually kill plants directly. They drain nutrients from the plant and excrete a sugary waste. This stresses the plant, retards growth and makes it susceptible to other diseases. The flies’ waste product grows black mold that destroys the forest floor and smells terrible.
Although the tree of heaven, also an invasive species from Asia, is its preferred food, spotted lanternflies are known to feed on 70 trees, shrubs and vines. Of agricultural concern are grapes, apples, peaches, plums, cherries and almonds. In the forest, they eat oak, maple, willow, walnut, poplar and many others.
This means that uncontrolled, lanternflies will negatively impact deer, bears, turkeys, squirrels and many other game and non-game species.
I live in the middle of a mixed deciduous/hemlock forest in Centre County. I weathered the gypsy moth plague in the early 1980s. Hundreds of the fuzzy caterpillars were crawling all over my house. You could not hang out laundry because of their droppings. Take a nap on a hammock? No way. One needed to drive slowly on country roads because in some places there were so many gypsy moths that they made the road surface slick.
By sometime in June, all of the mountains looked like they normally do in March — brown and bare. It was a sad state of affairs. Gypsy moths eat over 300 species, therefore the defoliation was nearly total. However, populations crashed, v-wilt killed many, an egg-eating wasp was introduced, and Bt — a larva specific bacteria — was used to control the population.
Penn State’s Lanternfly Call Center (888-422-3359) fields about 1,000 calls a week from people reporting lanternfly sightings or asking for information about how to control them. You can help by killing lanternflies, scraping and burning egg masses, and by reporting sightings — particularly in quarantine area edge counties, as well as from counties not quarantined.
Biologists are working across the United States, including at Penn State, to find a way to control the spotted lanternfly. My hope is that an answer is found before we have to endure yet another insect plague.