Along Chapman Highway in Knoxville, what seems to be a normal Arby’s with a retro sign has turned into a viral sensation. Social media users have likened its backdrop of trees blanketed in kudzu to a jungle, jokingly calling it “Jungle Arby’s.”
Kudzu is a woody, hairy vine with distinct three-pronged leaves. During the blooming season in late summer, the plant produces grape-smelling purple flowers.
Despite its initial lush beauty, the invasive vine outcompetes native species for sunshine, destroying habitats — something that has been accelerated by climate change.
“Kudzu is like a glamorous villain I think that everybody sees because it looks like a big monster and, you know, it’s ‘the vine that ate the South,’” said Ben Nanny, the conservation director at Ijams Nature Center.
Kudzu and climate change
Kudzu, native to Asia, was introduced to the United States as an ornamental plant at the 1876 Centennial Exposition in Philadelphia. During the Dust Bowl of the 1930s, the federal government used it to fight soil erosion.
However, the plant hides soil erosion under its soft leaves, as nutrients from the soil are washed away .
“The water just moves freely underneath it, and so you lose the habitat that it has overtaken that keeps the soil in place,” Nanny said.
Kudzu also increases nitrogen levels in the soil, impacting growth of native species. In turn, it puts the survival of wildlife who rely on those species at risk.
Its capability of rapid growth during summer months allows vines to grow up to a foot a day. As climate change is leading to longer warm weather conditions, kudzu is likely to spread farther.
One patch of kudzu sits just off trail in a shady grove near the nature center’s campus. Nanny said the kudzu patch has been trimmed down each season to prevent it from creeping farther into the woods.
“We've worked really hard to keep them in one space, but it’s constant work,” he said.
This method is one of several ways to control kudzu’s growth, but it doesn’t kill it.
The invincible plant
Each kudzu vine is attached to at least one energy-storing structure called a tuber, which looks like a skinny potato. They are established when a node on the vine makes contact with the ground.
According to the University of Tennessee’s Institute of Agriculture, tubers can reach several inches in diameter and grow as far as three feet into the ground.
“[Kudzu] will die back in the fall, and you think it's gone, but that tuber is sitting there with all of this starchy energy waiting to just burst back out on the scene in the spring and go through the summer again,” said Sam Adams, an arborist at the University of Tennessee.
To remove kudzu completely, experts like Adams spray rounds of legume-focused herbicides on the plant, a process that can take several years. The herbicides target the tubers, causing them to weaken over time.
At a greenway near Third Creek in Knoxville, Adams scans roughly 450 feet long containing a mix of native and invasive plants. He said this area was grown over by kudzu 10 years ago.
“It's really about diminishing returns from the plant,” he said. “The more we can keep it so that the plant gets fewer resources every year, the more likely we'll get it under control.”
Kasey Krouse, the city of Knoxville’s urban forester, stands along the bank of a creek that flows through Tyson Park, near the University of Tennessee’s campus. Across the creek is a sunny hillside covered in kudzu. Dead trees reaching 30 feet droop to the side, bearing the weight of hundreds of vines.
Habitats like this creek are called riparian zones, which are critical areas that maintain water quality and stabilize stream banks. The possibility of kudzu crawling to the other side of the creek poses a risk to reduce water quality due to soil erosion.
“We don't have a lot of native habitat and shade on that side of the creek,” Krouse said, pointing to the hillside. “It's not very good for biodiversity, good for the water quality and all the other things. And so this is a target area”
State and local governments across the Appalachian region are taking more initiatives to fight back the plant and restore native green spaces. Knoxville recently received a state grant to eradicate the invasive vine. The effort aligns with a master plan to identify and eradicate invasive species to preserve native species in public spaces.
“I think it's important for the city to be the leaders in this to show, one, this is how you can do it, and two, that it can be done,” Krouse said.
Raising public awareness of the plant
Jason Emory, who runs the landscaping company Knox Goats, deploys an army of 60 goats at a time to munch on kudzu. As his company has grown, he said more people are becoming aware of the risk the vine poses to native plants.
“When I first started, we were happy to get a kudzu job. You know, it's like people didn't really believe the process,” he said. “But now I would say probably half of our work is kudzu. People are starting to see it and understand that it is a problem.”
Some folks have taken the problem into their own hands, making soaps and wreaths out of the vines. This effort is encouraging to experts like Nanny.
“I think people's awareness of kudzu and other invasive species is a great thing, and it's a great thing for our city and moving forward and creating better green spaces for everybody,” he said.
This story is part of our Signal Species series exploring how the region's flora and fauna are adapting to a changing climate. It was produced by the Appalachia + Mid-South Newsroom, a collaboration between West Virginia Public Broadcasting, WPLN and WUOT in Tennessee, LPM, WEKU, WKMS and WKU Public Radio in Kentucky, and NPR. Sign up for the weekly Porch Light newsletter here for news from around the region.
