The spotted lanternfly was discovered for the first time in Pennsylvania in 2014, and it has since expanded to 26 counties in that state as well as at least six other eastern states. It’s making its way into New England’s southern reaches, as well as Ohio and Indiana.
This Asian insect, which is about 1 inch long and has lovely polka-dotted front wings, can infest and damage trees and plants.
Professor Frank Hale, an entomologist, is following this species’ progress.
What caused the spotted lanternfly to arrive in the United States, and how quickly is it spreading?
It’s native to India, China, and Vietnam, and it most likely came in 2012 as part of a cut stone shipment.
The first sighting was in 2014 on a tree of paradise in Berks County, Pennsylvania.
In the late 1700s, a common invasive tree was imported to North America from China.
The lanternfly had spread to about half of Pennsylvania, considerable regions of New Jersey, parts of New York state, Maryland, Delaware, and Virginia by July 2021.
It had also been discovered in western Connecticut, eastern Ohio, and, most recently, Indiana.
To give you an idea of how quickly these lanternflies spread, they were introduced into South Korea in 2004 and within three years had spread throughout the entire country, which is roughly the size of Pennsylvania.
What causes them to spread so quickly?
Lanternflies deposit egg masses on tree trunks and any smooth-surfaced item sitting outside in late summer and autumn.
The egg masses, which resemble smears of dry mud, can also be spread across the smooth surfaces of automobiles, trucks, and trains.
They can then be moved accidently to any region of the country in a matter of days.
After hatching, the eggs crawl to nearby host plants to begin a new infection.
What kind of harm do they cause to trees and plants? What do they eat to stay alive?
They eat sap by piercing the bark of trees and vines to gain access to the plant’s vascular system.
Lanternflies are quite large for a sucking bug.
They sap the tree and excrete huge amounts of transparent, sticky “honeydew,” which coats the tree and everything beneath it.
Wherever honeydew has been deposited, a black sooty mould forms. Sooty mould, while ugly, isn’t dangerous when it grows on or beneath the tree’s bark.
Lanternfly feeding puts trees and vines under a lot of stress, as they lose carbohydrates and other resources that would otherwise be stored in the roots and used for new growth.
Infested trees and vines grow slowly, show dieback (death starts at the branch tips), and can even die completely.
How are scientists and government officials attempting to halt the spread of these viruses?
Biological control has the potential to be a viable option in the future.
In the United States, two naturally occurring fungal diseases of spotted lanternflies have been discovered.
In addition, two parasitoid insects—insects that grow by feeding on lanternflies and killing them—are being tested in US labs.
That was brought in from China for testing and probable distribution in the future.
Should people be concerned about this lanternfly?
I’m very concerned. Lanternflies reproduce quickly and easily.
Lanternflies cause damage to crops, the forest, and the landscape in the area where host trees exist.
They harm a variety of plants and are a nuisance to the general people.
The heavy flow of honeydew, as well as the sooty mould that results, has wreaked havoc on the landscape.
In September, the adults begin to congregate on plants and structures to lay their egg masses.
People may be alarmed by their unexpected, mass emergence, similar to how periodic cicada populations alarmed people when they emerged from the ground.
But the infestations of lanternflies are even more frightening because the few predators that could eat them, such as wheel bugs and predatory stink bugs, don’t seem to be able to manage them.
As a result, the introduction of parasitoids from Asia is critical to attaining some sort of biological control.
Lanternflies can be a major pest of grapes, reducing grape yields and damaging or killing vines where they are found.
Insecticides must often be used multiple times to kill them, which raises the expense of crop cultivation.
The insect poses a threat to the East’s key wine-producing regions, including New York’s Finger Lakes and Long Island; sections of Virginia; and Newport, Rhode Island.
Have any other bugs harmed trees in the same way?
Yes, the emerald ash borer, which was accidentally introduced to the United States from China and identified in 2002.
In North America, it has killed millions of ash trees.
The Asian longhorned beetle, which feeds on and destroys a variety of tree species, has been discovered in a number of places, most recently near Charleston, South Carolina.
If this pest spreads, maple, buckeye, horse chestnut, willow, and elm trees would be harmed.
The box tree moth is a pest that attacks boxwoods and is found throughout Canada.
It’s been spotted in Connecticut, Michigan, and South Carolina, among other places. It may have arrived in the United States accidently in boxwood shipments from Canada.
Although it has not been confirmed in any state, a federal government order has put a stop to the import of host plants such as boxwood, euonymus, and holly from Canada.
What should I do if I happen to come upon one?
If spotted lanternflies have already contaminated your area and you locate them on your property, contact your local county extension office for control advice.
If it hasn’t been detected in your county or state, contact your state’s agriculture department.
If the infestation is identified early, before it has a chance to establish itself in your area, it should be able to be removed.
It will eventually spread throughout the country. We can slow the spread of the disease by detecting and removing new infestations as they appear.