Apr 26, 2023
Invasive Spotted Lanternflies Are Hitchhiking in the US
The colorful pests have recently been spreading across Indiana. Spotted
The colorful pests have recently been spreading across Indiana.
Spotted lanternflies like to hitch a ride on things. They lay their eggs on piles of cut wood, on plants, and on the metal sides of trucks and cars. Then they easily get transported to another location.
Their ability to travel so discreetly is what has helped these invasive insects keep spreading. Most recently, they’ve continued to migrate in Indiana and have now been spotted in at least a dozen states.
Adult spotted lanternflies (Lycorma delicatula) are about one inch long with large, distinctive wings. Their back wings are mottled patches of red and black with a white band. Their front wings are light brown with black spots.
As attractive as they are, their ability to wreak havoc is not so appealing.
"They feed on more than 100 species of plants, using their straw-like mouthparts to pierce plants and drink the sap. When large numbers of spotted lanternflies feed on plants, they cause general reductions in plant health and performance, and can even cause plant death," Elizabeth Long, Purdue University assistant professor of horticulture crop entomology, tells Treehugger.
"They are also a nuisance when feeding in large numbers around homes and landscapes because they produce a lot of sugary liquid waste, called honeydew, that covers the surface of patio furniture, plants, etc. that also attracts insects that feed on honeydew, like wasps and yellow jackets."
Most recently, the pests were documented in Huntington County in Indiana. The latest migration, say entomologists, poses a threat to wine grapes, as well as walnut trees and honeybees. They were first spotted in the state in Switzerland County in July 2021.
"The concerns for our state are similar to those raised by neighboring states in our region: This insect has the potential to have serious negative impacts to the wine grape industry, as well as hardwood nursery industries, including nut trees," says Long.
"Research is ongoing regarding negative impacts on other commodities, but we know from work in Pennsylvania that these insects readily feed on and cause damage to grapevines and nut trees."
Spotted lanternflies were first noticed in Berks County, Pennsylvania, in September 2014. They have spread to Connecticut, Delaware, Indiana, Maryland, Massachusetts, New Jersey, New York, North Carolina, Ohio, Virginia, and West Virginia.
Their egg masses are about an inch long and look like a "smear of mud," according to the United States Department of Agriculture.
"It has spread to other areas largely due to the unintentional movement of different life stages, but particularly the egg masses, which are hard to spot, even if you know what they look like!" says Long.
"Based on research to date, it is suspected that egg masses laid on the sides of railroad boxcars or other transport vehicles is the main way this insect has spread, despite all the hard work and quarantine efforts in Pennsylvania."
The insects lay their eggs on everything from vehicles to patio furniture. Because they’re so nondescript and small, the egg masses are often accidentally moved to other locations.
There are many ways that invasive species like this can affect ecosystems, which is why researchers are trying to learn more about spotted lanternflies.
For example, they can change interactions between other native organisms. The honeydew that spotted lanternflies produce can attract more sugar-feeding insects like wasps or ants. Then there's the domino effect of how these insects affect animals, plants, and people in the area.
"In the bigger picture, the presence and spread of these insects, combined with the absence of natural enemies that adapted with this insect in its native range, leave the door open for this insect to impact our ecosystems in a number of ways," says Long. "Via changes in plant-animal-insect interactions, as well as changes in human management strategies that may influence other insects in spotted lanternfly-affected areas."
Homeowners, farmers, beekeepers, and anyone who might run into the insects are encouraged to learn how to recognize the pests and their eggs and be vigilant for their presence on equipment, vehicles, or anything else you might be moving.
If you spot any, the USDA suggests scraping off any egg masses into a plastic zippered bag filled with hand sanitizer. Zip the bag shut and dispose of it.
"We do know that insecticides currently available on the market for homeowners and commercial farmers can kill these insects, but it is not necessary to spray if you do not have spotted lanternflies in your area," says Long. "Please be mindful of beneficial insects and pollinators, and do not spray if it is not necessary."
Before using an insecticide, she suggests contacting the local county extension educator or specialist for recommendations.
If you spot an insect you believe to be a spotted lanternfly, snap a photo of it and note the location and check with your state on how to report it.
"An important note I want to add is that spotted lanternflies are not a direct danger to people or pets," Long says. "They do not sting or bite, rather they glide around and hop, so no need to be afraid they will hurt you."
Elizabeth Long, Purdue University assistant professor of horticulture crop entomology
"Spotted Lanternfly." United States Department of Agriculture.
"The Spotted Lanternfly and Connecticut." Department of Energy and Environmental Protection.
"Spotted Lanternfly Now In Northern Indiana." Purdue University.