Spotted lanternfly a "shocking" expense to homeowners

The spotted lanternfly may be a beautiful insect — it has eye-catching bright red and spotted wings — that doesn't bite or sting. But the invasive species is proving to be harmful not only to farmers but to homeowners, who can face costs of thousands of dollars to eradicate the pests from their properties.

The problem begins with the spotted lanternfly's habit of excreting a substance called "honeydew," a sticky, sweet goop that falls from the insects as they feed on tree sap. Honeydew lands on homes, cars, decks and outdoor equipment, like grills, and is a growth medium for sooty mold — an unsightly fungus. The excreted substance is also attractive to bees and wasps, which can also spell trouble for homeowners. 

While there's no estimate on the economic impact for U.S. homeowners, it could be substantial, given that the cost to eradicate the spotted lanternfly from one property ranges between hundreds to thousands of dollars, according to experts. That's on top of projected economic costs from agricultural harm, which could exceed $300 million in Pennsylvania alone, according to a 2019 report from Penn State's College of Agricultural Sciences.

"The impact that it's had on suburban and urban environments has surprised me," said Jayson Harper, professor of agricultural economics at Penn State who co-authored a 2019 study on the economic toll of the spotted lanternfly on Pennsylvania's forest and farm industries. "It's been shocking to see the impact it has had on homeowners and parks departments."

Sitting under a tree infested with spotted lanternflies can feel like "raindrops falling" because of the honeydew they excrete, Harper added. "You might want to sit on your patio enjoying a meal and it drives you inside," he said. "People are spending a lot of money trying to control these things."

"Insect poop"

Among those people is entomologist Eric Braun, a technical services manager with Ehrlich Pest Control, who works out of Reading, Pennsylvania, in Berks County — the first county where the spotted lanternfly was found in the U.S. Braun said he noticed a few of the insects on his property at the end of 2019, but by earlier this year, they had multiplied to the point where it was a nuisance to sit outside. 

"When I sat on the deck, I would feel the honeydew dripping on us," Braun recounted. "Really what it is is insect poop. I didn't want to tell people they were sitting on my deck and getting pooped on."

Braun said he used a combination of topical and systemic insecticides to treat the infestation, with the former costing a few hundred dollars and the latter ranging from $1,000 or more, depending on how many trees need to be treated. Systemic insecticides are injected into the tree, so that when the spotted lanternfly feeds on its sap, it ingests the treatment and dies. 

Braun said he only treated the trees closest to his house on his two-acre property, which has more trees farther away from his home where he's also spotted the insect. But treating all of those trees could have cost him between $3,000 to $5,000, so he decided to focus on just the trees nearest to his home. 

There's an increase in demand for eradicating the spotted lanternfly from homeowners and businesses, noted Ben Hottel, technical services manager for pest-control company Orkin. 

"People don't want hundreds or thousands of spotted lanternflies in their yard or in front of their businesses," he noted. "If you have a couple in your yard, you can smush them, but if it's hundreds or thousands, you will really have to take more extreme measures to get rid of them."

Squishing the insect: "Not all that effective"

Officials are advising people to squish, stomp or kill spotted lanternflies when they encounter them. 

"Killing one or two may make you feel better, but it won't be all that effective," Harper of Penn State said. "People can do something, but it's a drop in the ocean." 

At the same time, it's not difficult to kill the insects with insecticides, Harper said. People can help control the spotted lanternfly by reporting sightings to state officials and checking their vehicles before leaving an area where the insects are known to exist. Because the spotted lanternflies are hitchhikers, they are using America's road and train systems to spread into new regions, Harper said.

"If you are at a park, check your car before you leave to make sure you don't have a hitchhiker with you, that you didn't bring one in the picnic basket," he explained. "If you want your kids to smash them, that's fine. But the main thing is just don't transport them."

After first arriving in Berks County, Pennsylvania, in 2014, the spotted lanternfly has expanded to more than three-dozen counties in the state, stretching from Philadelphia to Pittsburgh's Allegheny County. It's also in almost every county in New Jersey, while Connecticut, Delaware, Indiana, Maryland, Massachusetts, New York, Ohio and Virginia all have infestations, according to Cornell University's College of Agriculture and Life Sciences. 

There have also been sightings in states as far afield as North Carolina and Vermont, the Cornell college reported. 

Another effective control technique is to look for egg masses and remove them, said Orkin's Hottel. The spotted lanternfly lays its eggs in the fall — about now — which means destroying them now can help prevent an outbreak next spring or summer. 

"They can lay them on anything: a dumpster, someone's car, firewood," Hottel said of the insect's eggs. People can scrape up the egg masses, which can hold up to 50 eggs, with an ice scraper, a credit card or other hard-edged surface and then spray the remains with hand sanitizer or alcohol to kill the eggs. (You can see a video here about how to do this.)

"Catastrophic" threat to vineyards

The spread of the insect is alarming because of its impact not only on homeowners, but on farms and forestry, experts note. The spotted lanternfly is particularly drawn to a few types of trees and plants, including grape vines and tree fruits, although it is known to feed on the sap of more than 70 plant species.

The insect's threat to grapes is especially worrisome as the impact over a couple of years can be "dramatic," Harper said. Because the insect feeds on sap, it weakens the vine — and after a couple of years, the vine can die. 

"The speed that these things can attack a grape vineyard is pretty dramatic," he added. "The problem with grapes are they are very expensive to establish, and you think they will grow for twenty, thirty, forty years. It's not like corn where, 'I had a bad crop this year, but I'll plant again next year.'"

While there's no national estimate on the potential economic impact of the spotted lanternfly, Harper said the invasive pest would have a "catastrophic" impact if it were to reach California, which produces more than $40 billion of wine each year. 

Harper noted, "As far as I know, I'm the only crazy person who has done" an economic impact study of the spotted lanternfly. His 2019 research estimated that the worst-case scenario from the lanternfly would cause a $324 million economic hit to Pennsylvania alone and cause the loss of about 2,800 local jobs.

Vineyards have so far been the most adversely impacted agricultural commodity, said Erin Otto, national policy manager in the U.S. Department of Agriculture's (USDA) Animal and Plant Health Inspection Service (APHIS). 

"Some farmers have experienced a significant loss of their vineyards and others have reported varying level of losses to this pest," Otto said in a statement to CBS MoneyWatch. The USDA doesn't have a national estimate for the potential damage from the insect, Otto added.

"Pennsylvania represents just one segment of U.S. grape production, so we cannot estimate projected damages for grapes (or other crops)," Otto said. "We cannot quantify the damage that has occurred in a statistically significant manner, so we cannot predict real damage expected per crop or commodity."

Echoes of the brown marmorated stink bug

Slowing the spread of the spotted lanternfly is important in order to protect farms and property owners from damage and treatment costs, but also to provide scientists with more time to understand how to control the invasive insect, experts said. 

"One thing to keep an eye out for is the invasive tree of heaven — this pest's preferred host," Otto of the USDA said. "It can be found in many urban and suburban environments and can flourish in disturbed areas." 

The USDA also recommends reporting the sightings of the spotted lanternfly to your state's department of agriculture. "Every public report and all of the actions members of the public take to reduce this pest's spread helps," Otto said.

Harper of Penn State compared the spotted lanternfly to the brown marmorated stink bug, a pest that also originated from Asia and was first seen in Pennsylvania in the 1990s. By now, it has spread throughout most of the Eastern and Western states, and attacks a range of crops like apples and corn. But a parasitic wasp has been discovered that can help control the insect, Harper noted. 

"We found natural enemies that attack the brown marmorated stink bug — we are searching for the same thing for the spotted lanternfly," he said. "Based on previous efforts I've been involved with, we will get to the other side, but it takes time."