Have Americans Been Mercilessly Squashing a Creepy Bug for Nothing?

Kill-on-sight orders inspired people to go after spotted lanternflies with a (perhaps misguided) vengeance.

a spotted lanternfly wings through the blue sky

Updated April 7, 2022, at 10:58 a.m.

Squashing spotted lanternflies isn’t always easy. Maybe that’s obvious. Maybe you’ve tried it, after encountering kill-on-sight orders. The dotted, mothlike bugs tend to hop, after all, sometimes narrowly escaping the (almost) perfectly timed thud of a sneaker. So when you get one, you celebrate.

“See ’em? SQUISH ’EM!” reads one tweet, complete with a trophy photo of two bug carcasses stuffed inside tiny glass jars. “I KILLED A SPOTTED LANTERNFLY!!!” another exclaims. And another: “I can honestly say that’s the biggest adrenaline rush I’ve had all 2020.”

Haters have organized “squishathons” and spotted-lanternfly-killing pub crawls. “It’s kind of a crusade,” according to Brad Line, who lives in Pennsylvania. He developed an app called Squishr, which ranks users’ spotted-lanternfly kills, complete with gory photos as evidence, on a national leaderboard.

The motive for attacks of such self-congratulatory glee—and such careful viciousness—is supposed to be a dire environmental prognosis, our belief that the spotted lanternfly is a threat to Mother Nature herself. The bug’s wide-ranging appetite for at least 103 different plants worldwide, according to the latest research, has perhaps contributed to its reputation as an indiscriminate life-drainer. “If you see thousands of these very large insects feeding on your tree, then the first thought you’re going to have is That tree is not going to survive this,” Brian Walsh, a Penn State Extension educator, told me. Yet in the eight years since the bugs first made American backyards their home, some of the most shocking damage has come not from spotted lanternflies themselves, but from overzealous (and very human) attempts to stop them.

The bugs were first found in the United States in Berks County, Pennsylvania, in 2014, after supposedly hitching a ride as a bundle of eggs from China via a shipment of stone. Spotted-lanternfly infestations have since been documented in 11 states, but are centralized in the stretch of Eastern Seaboard from Virginia to New York. Female spotted lanternflies can pop out 30 to 50 potential offspring packed tightly into an egg mass smaller than a human thumb. A single tree can host more than 12,000 of the grown sap-suckers across one week.

When the lanternflies showed up here, the “really problematic” proclivity for grapes and stone-fruit crops they had already demonstrated in South Korea alarmed researchers, according to Emelie Swackhamer, who educates locals on the invasive bug for Penn State Extension. Even after Korean vineyards were sprayed with pesticides, spotted lanternflies were reported to “rapidly repopulate,” swarming in from adjacent wooded areas. They can devastate grape crops by feeding on sap and excreting a substance called honeydew, which causes black-mold growth, Kelli Hoover, a Penn State entomologist who studies the insect, told me. So worries were, in part, justified: A 2020 study found that among a sampling of Pennsylvanian vineyards, higher densities of spotted lanternflies were linked with a decrease in fruit production and overall vine health. Hoover has heard of entire vineyards succumbing to spotted-lanternfly-induced stress.

“It is the most unusual insect I’ve ever studied,” she said. “It’s probably the hardest to do research on”—in part because of its voracious appetite. Scientists have been able to raise another invasive bug, the Asian long-horned beetle, on maple branches, logs, and even an “artificial diet,” Hoover told me. Spotted lanternflies survive on potted trees—if they’re swapped out every few weeks. And even then, they don’t thrive like they would in nature. Researchers still don’t have a grasp of key facts, such as exactly how far spotted lanternflies can travel in their life span, or key defenses, such as how best to trap them.

So, sure, the spotted lanternfly isn’t really a bug you’d want to cozy up to. But maybe its critics have all been a little hasty to judge so hard.

Take, for example, economic impact. In 2019, a report from Penn State projected that spotted-lanternfly-related damage in total could cost Pennsylvania more than $324 million annually if the bugs continued to spread. But Erin Otto, a national-policy manager in the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, cautions that, so far, “damage to vineyards in Pennsylvania has been scattered and inconsistent.” She would need to see more research before putting a dollar amount to the totality of harm.

Then there’s this odd and inconvenient fact: Lately, spotted-lanternfly numbers appear to have dropped off in certain zones where they once multiplied like crazy, and not necessarily as a direct result of human action. And another one: Aside from the occasional tree of heaven—a fellow invasive and the spotted lanternfly’s snack of choice—“they’re not really killing trees,” according to Anne Johnson, a researcher and Ph.D. candidate at Penn State.

Perhaps the urge to annihilate the spotted lanternfly is overkill. At the very least, going after the bugs one by one has been an ineffective solution—and not without collateral damage.

In rare moments, Line, the Pennsylvanian behind Squishr, speaks about the spotted lanternfly with full-blown admiration. Its red coloring is striking, if you’re into that sort of thing. Mostly, though, he doesn’t hold back in expressing his disgust with the “nasty” bug. When enough of them congregate high up in trees, their honeydew can drizzle down like sticky rain on innocent people below. “It’ll get all over you,” Line said. “Some people can’t sit outside in their backyard, because these things are all over the place.”

Mix in instructions from the Pennsylvania Department of Agriculture to squash spotted lanternflies and report their whereabouts, and you’ve got the perfect civic-minded incentive to kill. “We knew that they were bad bugs,” Line said. He created Squishr in 2019 at the behest of his two sons, Nolan and Greyson, who’d become avid spotted-lanternfly killers themselves. A few years later, the app’s been used to record the squishing of almost 200,000 of the bugs.

“There are die-hard users who have been using it for the last few years,” Line said. “It’s a way to be part of a community … to be showing people that you’re doing your part.”

The zeal, though, can go too far—especially among those at wit’s end. In 2018, while working as a landscaper, Walsh, of Penn State Extension, fielded a request to check out a tree that was, apparently, well on its way to death-by-spotted-lanternfly. At his new client’s home, Walsh found an oak in poor health; branches on the lower fourth of the tree had yellowing leaves. Notably absent—at least in any alarming number—were spotted lanternflies.

After a round of questions (what attempt had the tree’s owner made at combatting the bugs?) and a telling observation (splotches of dead grass beneath the tree’s canopy), Walsh came to a sinking realization: His client had done the damage herself. Instead of using an insecticide, she’d mistakenly sprayed an herbicide called glyphosate, the active ingredient in Roundup, as high as she could reach.

“People can get very bent out of shape,” Walsh said, “and declare all-out war” on the lanternflies. He’s heard of Pennsylvanians running propane torches up and down the trunks of their trees; he’s heard of people dousing plant life with kerosene, engine-starting fluid, and oven cleaner to deal with the pesky bugs. Initially, Walsh told me, there was confusion as to whether common pesticides could legally be used to kill spotted lanternflies in the state (because the critters weren’t listed on any labels). Turns out, they can.

“There’s a lot of irresponsible behavior to try and manage these guys,” Anne Johnson said. “I’ve seen people say, ‘Oh, I use a can of hairspray and I light it on fire,’ and I’m like, ‘Um, that’s going to do way more damage than these guys did.’”

It’s easier to garner support for any cause—bug genocide included—with a rallying cry. In the case of the spotted lanternfly, the label “invasive species” has been enough to work people into a frenzy.

Language can shape human vendettas against foreign plants and animals, Dov Sax, a Brown University professor and ecologist, told me. The USDA defines invasive species quite succinctly, as non-native living things likely to pose a threat to the environment, the economy, or human health. But some ecologists have been pushing for a while now to underscore that non-natives aren’t always bad news; they just tend to be framed that way. In 2011, Mark Davis, a Macalester College professor emeritus and ecologist wrote an article, along with 18 other experts, urging fellow scientists to examine more critically their treatment of non-native species, much to the ire of more than 100 others in the community who signed, in response, a letter suggesting that to not watch non-native species with a skeptical eye would be foolish. Ecology debates aside, emotion-laden slogans do tend to make glamourless jobs sound sexier. “There’s the ‘War on Drugs,’ ‘War on Poverty’—War on Non-Native Species,” Davis told me.

In the beginning, there was a glimmer of hope that stomping out spotted lanternflies—literally—might stifle their spread. The past few years, many in the invasive bug’s orbit have resigned themselves to a different vision of the future. “We’re going to have to learn to live with them,” Hoover said.

After spotted lanternflies were first found in Staten Island, New York, in the summer of 2020, a new generation of do-gooder bug-squishers was born. But some back in Pennsylvania are losing steam. “The fatigue sets in after a couple years,” Line said. People start feeling “this kind of hopelessness that Well, there’s nothing we can do.”

Really, no one person can control the world in this way; the spread of non-native species seems, at this point, like a fact of life. And yet the anxiety persists, most recently swirling around the joro spider, the latest Asian bug to make news for its impending sprawl up the East Coast. This time, Americans are being told the “invasive” arachnid is unlikely to cause any harm at all—on the contrary, it might even keep other pests in check. We don’t need to lift a finger or stomp our feet. Can we resist the squish?