2020 has been horrible for most of us, and Pennsylvanians have found a new reason to add to the list. The spotted lanternfly, an invasive species from Asia, swarmed eastern Pennsylvania in a record-breaking infestation. Pennsylvanians, like me, have found it more than a little alarming to see hordes of this invasive planthopper in our own backyards. Pennsylvania Agriculture Secretary Russell Redding said, in a March press release, that the spotted lanternflies are “wreaking havoc for home and business owners; kids who just want to play outside; Pennsylvania agriculture and the economy of the state we all call home.” Want to know more about how you can be a part of the solutions to this pesky problem? Read on!
How can I identify the spotted lanternfly?
Depending on the season, spotted lanternflies are found in a few different life stages. In the spring, young nymphs are quarter-inch black insects that are occasionally mistaken for ticks. Later in the lanternfly’s life cycle, they take on a red coloration, still with white spots and black lines throughout, and eventually molt to adults with working wings. As we approach the end of fall, the most common stages of the lanternflies that you will see are adults and egg masses.
Adult lanternflies, which peak in population during the summer and fall months, are the largest and easiest to spot. Adults are about one inch in length and black, grey, and red in color with black spots covering their wings.
The egg masses of lanternflies can be difficult to find because of their tan color and smooth mud-splash-esque exterior but are nevertheless important to search for. Lanternflies lay their eggs on virtually any hard, smooth surface, including on cars, cushions, bark, and more. Destroying these egg masses is one of the most simple ways to reduce their spread.
Spotted lanternfly life stages and sizes. Credit: Towamencin Township
How did the spotted lanternfly get here?
The spotted lanternfly, native to China, India, and Vietnam, is believed to have been introduced into the United States as egg masses on a shipment of stones in 2012. The first infestation of the lanternfly was found in 2014 in Berks County, Pennsylvania, just northwest of Philadelphia. The state made efforts to contain the lanternfly locally while there was still hope of preventing an outbreak. Unfortunately, they were unsuccessful. The lanternflies began to spread rapidly to other Pennsylvania counties and eventually to surrounding states.
What is the environmental and economic impact of the spotted lanternfly?
The spotted lanternfly has devastated landowners and farmers in Pennsylvania, and its effects are only getting worse as it infests new counties.
Environmental Impact
When lanternflies feed on trees, stems, and vines, they excrete a substance called honeydew. While it sounds sweet, this sugary substance is a breeding ground for sooty mold, which can kill plants by blocking sunlight from reaching their leaves. While harmless to human health, sooty mold still causes issues for homeowners whose outdoor spaces can become overrun by dark, sticky substances. Talk about putting a damper on the family barbeque!
Economic Impact
In 2019, a report released by The Center for Rural Pennsylvania determined that these insects have the largest effect on the grape market and have the power to spoil up to 50% of grape crops in serious infestations. The study also estimated that spotted lanternfly infestations have cost PA $50.1 million annually and have eliminated nearly 484 jobs annually due to the reduction of agricultural and forestry output. These losses are a large part of why Pennsylvania and its surrounding states are so keen on controlling their lanternfly populations.
Which states have the spotted lanternfly spread to?
There are spotted lanternfly infestations in Pennsylvania, Delaware, New Jersey, Connecticut, Maryland, Virginia, West Virginia, and Ohio. There have also been sightings of spotted lanternflies in North Carolina, Massachusetts, and New York. The largest and most severe infestation still remains in southeastern Pennsylvania.
Spotted lanternfly distributions from October 2020 with blue sections indicating infestations and purple dots representing sightings. Credit: New York State Integrated Pest Management
What are some regulations in place to control spotted lanternfly populations?
The first line of defense is a quarantine zone around the infested counties in Pennsylvania. A quarantine prohibits the movement of material that could harbor the lanternflies, like firewood, across the quarantine line (seen outlined in red on the map above). Commercial vehicles and personal drivers can apply for exemptions to move these items responsibly across the zones but must submit to thorough inspections.
There have been some other, more complicated control methods that scientists have been researching. One of those projects is introducing a predator species, the tiny Chinese wasp which would kill baby spotted lanternflies by laying eggs in them. However, adding an introduced species in response to invaders is risky. Research is being conducted on a small scale to determine the viability and safety of this project. Another strategy has been training scent detection dogs to sniff out spotted lanternfly egg masses in order to destroy them.
Photo: Rosie Emerson: The view of multiple spotted lanternflies outside my sixth-floor apartment window in Willow Grove, PA, this summer.
What can we do to address spotted lanternflies?
The state has encouraged property owners to actively destroy egg masses on their property, using rubbing alcohol to ensure they don’t hatch unexpectedly. Although egg masses can be difficult to find, this practice has a distinct advantage over trying to capture and kill a flying adult lanternfly.
In order for any of these efforts to be successful against the spread of spotted lanternflies, we will need to work together and remain vigilant, taking the extra time to stay informed and check our vehicles before exiting the quarantine zone. Agriculture Secretary Redding remarked that “We need to unite over our hatred for this pest for our common love: Pennsylvania.”
Thank you so much for taking the first step to fighting this invasive insect. To find more information or to report sightings of spotted lanternflies, please visit the Penn State Extension website here.