The vine that ate the south is here
I was planning to continue my series on garden design this week with shade gardening, but something important came up, and I didn’t want to wait.
No, it isn’t the brown marmorated stinkbug that is invading everyone’s homes. I’ve written several columns about that particular pest. (To read more about them, go to www.tribtoday.com/page/content.detail/id/577190/ Should-we-be-making-way-for-the-stink-bugs-.html.)
This is another invasive, foreign pest that has been slowly migrating our direction. For those who travel to the southern states, you know what I mean when I say kudzu.
Ohio State University Extension educator Amy Stone from Lucas County posted a disturbing message on Facebook last week. Kudzu is in Cleveland. She also posted photos of the vine she said was growing in a commercial / industrial site on the edge of a residential neighborhood.
”It is over fences and up over the top of trees,” Stone said. ”It was growing out into the stone parking lot and developing roots when it came in contact with the ground. This plant knows how to grow – that’s for sure!”
Kudzu, Pueraria lobata, is a perennial vine that can reach up to 100 feet in length. Not native to the United States, it was first brought to this country in 1876 from Japan at the Centennial Exposition in Philadelphia and was introduced in the south in 1883 at the Louisiana Exposition. It was praised in newspapers articles in the early 1900s as a wonderful plant for growing on arbors to provide shade. By 1930, farmers were advised to plant kudzu, a legume and therefore relative of beans and peas, as a cover crop to enrich the soil. It was also recommended as fodder for livestock but it was later determined that cutting, hauling and bailing the vines wasn’t easy or cheap. Even the U.S. Department of Agriculture got on board by suggesting planting kudzu to prevent soil erosion.
Now considered an invasive pest, you only have to take a drive through Tennessee, the Carolinas and most other southern states to see how this plant’s rapid growth can cover everything from the tallest trees to buildings, utility poles and wires and anything else in its path. Once, when visiting relatives in southern North Carolina, our hosts advised, ”See that plant that is shaped like a car? There really is a car under there.”
Kudzu is believed to spread primarily by runners, which are rhizomes that root underground. The vines also readily form roots at each node along their stems and these roots, if left to grow underground, will form rhizomes. One main plant is said to have a massive taproot that can expand up to seven inches in diameter and be more than six feet long. Each root can produce as many as 30 vines.
Freezing temperatures can kill young vines back to the root, but it doesn’t kill the root. When the weather warms, the growth begins again. Older vines aren’t killed by frost.
Leaves grow alternately on the vines and are made up of three broad leaflets that can grow to four inches across. The leaves are hairy and are deeply lobed. The purple flower clusters bloom in late summer later forming flat, brown seedpods that also are covered with hairs. Each seedpod contains from three to 10 seeds.
Kudzu was first found in Ohio in 2009. By 2011, it was identified in 22 counties, a number that has since increased.
”We are trying to encourage people to look for it so we have a better handle on where it is,” Stone said.
Not yet in Ohio but hot on the heels of kudzu is the kudzu bug (Megacopta cribraria). This foreign pest was first identified in Georgia in 2009 and as of this year, its migration throughout Tennessee is being recorded at kudzubug.org.
To some, this might seem like good news that this invasive plant actually has an insect pest to eat it, but because kudzu is a legume, the bug also chows down on beans, soybeans and ornamental plants in the same family, like wisteria.