by Caitlyn Johnstone
August 15, 2018
If you are a fan of wine, beer, fruit or being outside in nature, be on the lookout for a brightly colored bug: the spotted lanternfly. Native to Asia, the spotted lanternfly has made its way to parts of the Chesapeake Bay region, where it is wreaking havoc on vineyards and orchards. It was first seen in Berks County, Pennsylvania in 2014. Since then, 13 counties in the state have been quarantined, with individual insects spotted in Delaware, New York and Virginia.
The adult lanternfly has two different colored sets of wings which fold over its body and are designed to protect it from being eaten. When at rest, a lanternfly’s dusky colored, black spotted top wings help it blend into its surroundings. If it is spotted and disturbed, it will spread both wing sets to reveal brilliant reds on the lower wing set and body, warning potential predators, “Hey, I might be poisonous.”
Lanternflies are plant hoppers and sap suckers, and there are at least 50 plant species identified so far in our region that they find tasty. They don’t fly very well, but instead hop from plant to plant sucking out sap. What we call sap is phloem, the vascular tissue in a plant that transports sugary nutrients. Instead of eating fruit or leaves, the lanternfly weakens the plant overall by sucking the sugars straight out of it. This can be devastating for plants.
“Lanternflies have to suck out so much phloem to get the nutrients that the excess just comes squirting out [of the insect],” explains Mike Raupp, entomologist for the University of Maryland Extension. The excretion, given the deceptively charming moniker “honeydew,” “just rains down on everything,” says Raupp. This sugary blanket brings sooty mold, entices other insects and has an inhibiting effect on the natural functions of the leaves. Vines not feasted upon are sickened anyway by the blanketing rain of sticky lanternfly leftovers.
Young lanternflies emerge from their over-wintered egg cases in May as nymphs, becoming winged adults around August. The egg cases laid by adults are small, dark, thin and hard to spot, making them easy hitchhikers. Lanternflies will deposit their eggs on trees but also on houses, wooden furniture, trailers, cars, fenceposts, stones and anything else relatively smooth. If humans do not help each other keep an eye out, people will be the means of lanternfly infestations spreading beyond the quarantine.
Real world impacts
Just enjoying the outdoors can also be impacted. If you’re in an area that has lanternflies, watch out for stings from wasps, hornets and yellowjackets. While lanternfly itself does not sting, “stingers are going to be attracted to the honeydew,” says Raupp.
Lanternflies are particularly damaging to vineyards and the wine industry. For the first three years of a vine’s life, a vintner will strip all the grapes so the plant puts energy into making a robust vine. A strong vine leads to wine-quality grapes. Vintners continue the vine-strengthening process in later years, cutting back the total number of grapes on healthy vines to further concentrate flavors. The lanternfly, instead of damaging a grape cluster, sucks the life out of the vine itself. If the vine survives, it will be years before it is able to produce wine-quality grapes again. According to a 2017 economic report, the wine industry brings in 4.8 billion dollars annually to Pennsylvania.
The lanternfly is not discerning when it comes to plants. It likes grapevines, but it also enjoys sucking on hardwood trees, hops and fruit trees. When a lanternfly infestation hits an orchard, saving any of the crop is difficult. “It just rains down honeydew,” continues Raupp, describing the lanternfly as a giant, Godzilla-like version of an aphid; “It fouls foliage, it fouls fruit.” Honeydew rain coats the tree, making the harvest unsuitable for sale.
Pennsylvania is the nation’s largest producer of hardwood timber products, bringing in approximately five billion dollars to the state annually. It is unclear how the timber industry may be affected by the spotted lanternfly setting up home in the watershed, but high lanternfly populations can cause weakness and dieback in trees.
If one invasive species weren’t bad enough, spotted lanternflies have been thriving in the northeast thanks to another invasive: tree-of-heaven.
Tree-of-heaven was brought to North America from China in the 1700s and quickly became a popular shade plant. The selling points for tree-of-heaven turned out to be the problems: it grew quickly, reproduced easily and had few predators. Soon tree-of-heaven was popping up in landscapes never intended, including sidewalks and rock walls. It also has alleopathic qualities, meaning it mildly poisoned the soil around it, further ensuring its takeover.
Tree-of-heaven, firmly established throughout the watershed, is the host plant for spotted lanternfly. The plant’s presence creates a welcoming environment for the spread of the invasive bug now threatening large industries and regional economies.
A growing response
Scientists are looking to the lanternfly’s native land for a solution. Researchers with the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) are working with researchers in Asia to study parasitic wasps that attack the lanternfly. Juli Gould, a scientist with APHIS, is rearing colonies of the wasps and studying the potential impact. “In all classical biological control programs (where one releases parasitoids from the native range of the pest), host specificity is the biggest concern,” writes Gould in an email. This means they have to make sure the wasp will target only the invasive lanternfly and nothing else. The United States has several native plant hopper species; researchers will do multiple tests in quarantine to ensure native insects won’t unintentionally fall victim to the wasps.
Vintners, farmers, arborists and members of other at-risk industries in the region are trying to be proactive by learning how a lanternfly invasion could affect their livelihoods and what can be done to prepare. Many environmental or agricultural organizations, soil and water conservation districts or university extensions are offering classes on recognizing the lanternflies and preparing for the impact to a particular industry—check with those in your area.
What you can do
You can be the first line of defense against the lanternfly. Familiarize yourself with what a lanternfly looks like in its different stages. If you are near a quarantine area, carefully check over all equipment and vehicles for egg cases before moving. If you see what you think may be spotted lanternflies or their egg masses, inform your state’s appropriate office as soon as possible. Include when and where you saw it as well as any specimens or photos.
- Delaware Department of Agriculture: HitchHikerBug@state.de.us, (302) 698-4586 or fill out this survey
- Maryland Department of Agriculture: (410) 841-5920 or DontBug.MD@maryland.gov
- New York State Department of Environmental Conservation: firstname.lastname@example.org
- Pennsylvania Department of Agriculture
- Penn State Extension: 1-888-4BADFLY (1-888-422-3359)
- Virginia Cooperative Extension
If you have tree-of-heaven on your property, consider having it removed or work with experts in your area to have it used as a trap: female trees are removed to prevent seed dispersal while a few males are kept as Trojan horses and fitted with sticky bands around the trunks. Lanternfly nymphs become trapped in the sticky tape as they walk up and down the tree.
Insecticides have been shown to be effective, though they can have their own double-edged effect on the environment. Raupp advises people to target the spotted lanternfly at the egg and nymph stages, saying, “it takes a lot more to get a big guy drunk than a little guy.”