Their names sound like something out of a comic book: the spotted lanternfly, the yellow-legged hornet, the Joro spider. But for scientists and farmers, invasive insects aren’t just science fiction—they’re a real and rising threat.
While you may only notice them as a shimmer in the trees or a crunch beneath your shoe, a 2021 study estimated that invasive insects could cost North America more than $27 billion a year. Researchers at the University of Georgia are making it their business to determine which invasive insects are harmless curiosities and which are ticking time bombs capable of upending ecosystems and ravaging crops.
What is an Invasive Species?
Not every foreign insect is invasive. Some, like banana spiders or the seven-spot ladybird, have been around so long they’re mistaken for native species. Instead, they’ve quietly blended into the ecosystem without major impact. These “non-native” or “exotic species” are classified as insects that were introduced to an area where they don’t naturally occur.
For a species to be invasive, it must be non-native and cause harm. Will Hudson is a professor and Extension specialist at the University of Georgia. He says that many of the insects causing a stir are so new that we don’t know what impact they are going to have on our environment or economy.
“Take the Joro Spider for instance,” says Hudson. “They’ve kind of exploded over here, but they’re on the border of being invasive. We haven’t been able to identify any major negative impact from Joros on the environment or other native insects. Still, because their webs and the sheer numbers are such a nuisance for people, we consider them invasive.”
The spotted lanternfly is another newer invasive species that is raising concern. A striking black, white, and red insect from Asia, the spotted lanternfly was first spotted in the Pennsylvania woodlands but has now traveled to more than a third of the country.
“My daughter lives in New York and she was sending me pictures of buildings where whole sides were covered with these bugs,” says Hudson.
Unlike the Joro Spider, the spotted lanternfly is expected to cause significant economic and environmental damage. Their victims? You may want to stock up on wine while you can.
Invasive Insects and Agriculture
Among the spotted lanternfly’s favorite food sources is the sap from grapevines. In states where the insect is already established, the estimated value of grape and tree fruit industries is $915 million.
“Though small in size, their potential to disrupt the grape industry is massive,” says Hudson. “Wine grapes. Table grapes. Muscadines. They’ll feed on all of those. And if they contaminate grapes meant for wine, the taste of that wine could be ruined.”
The brown marmorated stink bug is another example of non-native pests wrecking agriculture. It came over from East Asia in the early 1900s and caused extensive damage to apple orchards and vineyards in the Mid-Atlantic. Fortunately, as it moved south, its impact declined. This was partly due to the region’s hotter, more humid climate and an abundance of native stink bug species, which diluted its dominance.
“Insect development is temperature-dependent,” Hudson says. “So while warmer climates can speed up their life cycle, if they’re not well adapted to our conditions, they may not thrive.”
Still, with insects adapting quickly and spreading stealthily, experts stress the importance of early detection and rapid response to safeguard the future of American agriculture. One of the most critical factors in managing these outbreaks: stopping them from getting here in the first place.
How Do Invasive Species Spread?
Invasive insects don’t need wings to travel across states or even continents. They have found an effective way to travel the country with little effort: human beings. Insects like the spotted lanternfly can attach themselves to or leave their eggs on ships, cars, trains, planes, and anything else that moves long distances.
“If you take your RV from New Jersey down to Florida for the winter, you never know what may have hitched a ride,” Hudson says. “They’re more than willing to lay their eggs on the side of your car, truck, or most anything else. So unbeknownst to you, you’re helping them get around.”
Global commerce is one of the biggest culprits for letting in invasive insects. Yellow-legged hornets take advantage of their long hibernation periods when new queens crawl into a crack or crevice somewhere on a shipping container to spend the winter. They generally don’t emerge until the next spring and start a new colony wherever they wake up.
“If you’re talking about a boat,” Hudson explains, “it’s almost always the eggs that travel. They’re hardy enough to survive the journey.”
Once an invasive species is here, sending it back or completely eliminating it is virtually impossible. So, what do you do?
What Should You Do with Invasive Insects?
You don’t need a degree in entomology to protect your community from invasive insects. You just need your eyes, your phone, and a little curiosity. According to Chuck Bargeron, director of the University of Georgia’s Center for Invasive Species and Ecosystem Health, the public is often the first line of defense in identifying new threats.
“If you see something that looks unusual, make sure you let someone know about it,” Bargeron says. “Because that’s how we can catch the next problem early on—and do something about it before it becomes a lot more difficult and a lot more expensive to respond to.”
Over the past 20 years, Bargeron’s team has developed apps and websites—like the widely used EDDMapS (Early Detection & Distribution Mapping System)—to make reporting easier. These programs allow everyday people to learn about invasive species and report sightings in real-time. Users can simply snap a photo and upload it, and experts are alerted to verify and respond.
“The public is already out there enjoying state parks, camping grounds, and your own backyards,” says Bargeron. “This makes you our best first detectors. There have already been numerous times that a new species was reported this way.”
You may not even realize that some of the insects buzzing around your lunch or fertilizing your garden are part of an invasive species. There are many different ones in the United States, including the:
- Brown Marmorated Stinkbug
- Asian long-horned beetle
- Emerald ash borer
- Asian giant hornet
- Asian tiger mosquito
If you spot something strange—whether it’s an unusually large hornet, a beetle with zebra-striped antennae, or a web unlike anything you’ve seen before—don’t ignore it. Contact your local county extension agent or forestry commission or use one of the mobile tools to report it.
