‘Vine that ate the South,’ kudzu continues to spread
KRT LIFESTYLE STORY SLUGGED: HOME-KUDZU KRT PHOTO BY KIM KIM FOSTER-TOBIN/THE STATE (October 13) Newt Hardie is working to rid as much of South Carolina of the invasive plant kudzu as he can. He is shown at a patch in Columbia, South Carolina, on October 1, 2005. (gsb) 2005
AKRON, Ohio — Kudzu has been called the vine that ate the South.
Now it’s the North’s turn to struggle with it.
Kudzu patches have been reported in Summit, Portage and Cuyahoga counties, said Kathy Smith, Ohio State University Extension program director in forestry. In fact, it’s been found as far north on our continent as Ontario and British Columbia.
That doesn’t necessarily mean the aggressive vine will soon drape Northern U.S. hillsides and choke its trees. It’s believed the growing season in some northern climes is too short to allow the plant to flower and produce fruit, which keeps kudzu from spreading rampantly.
But that could change, said James Bissell, curator of botany at the Cleveland Museum of Natural History.
The changing climate is warming our winters and stretching our growing season. Eventually the conditions could become ripe for kudzu to flourish in our area.
“With global climate change, it could be a problem,” said Bissell, who tracks the distribution of plants in Ohio. “I expect it will be a problem.”
Kudzu, or Pueraria montana, is a perennial climbing vine native to Asia. It was introduced to the United States as an ornamental plant at the Philadelphia Centennial Exposition in 1876 and has also been grown as forage for livestock.
Its biggest boost, however, probably came from the U.S. Soil Conservation Service, which in the 1930s and ‘40s promoted its use for erosion control and even paid farmers to plant it.
Without the natural controls found in its native range, the vine grows prolifically, gaining as much as a foot a day in the hot South and spreading underground via a stout, deep root system. Andrew Londo, coordinator of extension forestry with Mississippi State University, said he has a photo of one particularly large kudzu tuber that “looks like something you’d see on a logging truck.”
The vine blankets just about everything in its path, including fences, buildings, trees and power lines. It smothers other plants and sometimes breaks off their branches or even uproots them.
Kudzu is already becoming a problem in the Ohio River valley, where the climatic conditions allow the plant to produce fruit. The seeds are spread by wildlife and even by mowers, vehicle tires and shoes.
In the Ohio area, the vine dies back to the ground in winter, but the root system remains alive, said Rick Gardner, a botanist with the Ohio Department of Natural Resources’ Division of Natural Areas and Preserves. That winter die-back slows the plant’s growth but doesn’t stop it.
Bissell said he has collected kudzu only once in Northern Ohio, on the property of a building supply company on Cleveland’s East Side. He suspects the vine was planted there intentionally and said it had spread all over a fence and the nearby houses.
Even though kudzu is still uncommon here, Bissell and other invasive plant specialists hope people will keep an eye out for the vine and report suspicious patches.
The plant has compound leaves made of three leaflets that form a roughly heart-shaped cluster. The leaflets grow to 3 to 8 inches long and 4 inches wide, and they’re green to yellow-green on the upper side and pale green beneath. The leaves drop off in fall. In areas where the growing season is long enough, the plant produces spikes of tiny purple flowers and hairy seed pods about 2 inches long.
You can use a smart phone app from the Great Lakes Early Detection Network to send a photo and request verification. The app can be downloaded at http://go.osu.edu/GLEDN.
Controlling the plant is challenging. A small infestation can be kept from spreading by cutting it or allowing livestock to graze on it, OSU’s Smith said. But killing the plant requires chemicals, she said.
Mississippi State’s Londo said the herbicide Escort is effective but must be applied by a certified professional.
He said a do-it-yourselfer can try cutting off the vines and immediately spraying the stumps with a strong solution of glyphosate. That’s the chemical found in Roundup, but most forms of the product aren’t strong enough to be effective, he said.
He recommended buying glyphosate in concentrated form and mixing a solution of one part glyphosate to three parts water.
Treat the kudzu as soon as you can, Londo advised. The longer it lingers, the bigger its tubers get and the harder it is to kill.