Kudzu: A Story Ripening on the Vine — The Environment at 5280

The usual biodiversity hotspots in the United States are thought to be Hawai’i, the Rocky Mountains, and maybe even Alaska; however, conservation biologists are looking closer at the Southeastern United States, describing it as one of the world’s biodiversity hotspots. E.O. Wilson reported that the central Gulf Coast states “harbor the most diversity of any part of Eastern North America and probably any part of North America.” The warm summers, mild winters, and plentiful rainfall make this region suitable for plants and animal species alike. However, this same climate and region that is pristine for native biodiversity is also prime habitat for one of the most infamous invasive species in the Southeast: kudzu.

Kudzu was brought to the United States in 1876 at the World’s Fair Centennial Exhibition in Philadelphia. Kudzu was touted as an ornamental garden plant and perfect for providing shade for porches. However, farmers at the time found the plant to be of little use, as the vine could take years to establish, was impossible to harvest, and could not tolerate sustained grazing from cattle and horses.

It was not until the 1930s that the vine became widely planted across the South. During the Great Depression, intensive cotton farming depleting nitrogen from the soil and widespread drought across the South exacerbated erosion. Between the 1930’s and 1950’s, the Soil Conservation Service encouraged Southern farmers to plant kudzu as a cover crop to prevent erosion and restore nitrogen to the soil. Thriving in disturbed, sunlit habitats where it was planted, kudzu spread rapidly due to its hardy deep root system and drought resistance. During the expansion of interstates and railroads, developers used kudzu to cover and stabilize steep embankments, often too steep for other plants to take root. However, this miracle plant soon became a nightmare plant. In 1998, Congress listed kudzu under the Federal Noxious Weed Act.

Kudzu has become so pervasive it has become colloquially known as “the vine that ate the South.” The United States Forest Service estimates that kudzu now covers at least 227,000 acres of forestland across the South. As an invasive species, kudzu often outcompetes native grasses and mature trees. Kudzu is able to cover entire trees and block any sunlight from reaching the tree, thereby eventually suffocating it. This harms not only the native plants, but native animal species that rely on such plants. Additionally, climate change also allows kudzu to spread farther north as winters become milder. Climate change adds additional stress to native species and invasive species, such as kudzu, are better able to thrive in these conditions. It is not only wildlife that kudzu covers up, but it has also begun to cover up American history. Kudzu is a major concern throughout the South due to the Civil War sites, national forests, and national parks. Vicksburg National Military Park, Chickamauga National Military Park, Chattanooga National Military Park, and Great Smoky Mountains National Park are all on defense trying to stave off the spread of kudzu.

In February 1999, President Clinton signed Executive Order 13112. This created the National Invasive Species Council and required a Council of Departments to deal with invasive species. The goal of the Executive Order was to control and minimize the economic, ecological, and human health impacts invasive species cause. Along with the executive order to curb invasive species, several states across the South implemented their own regulations to curb kudzu’s spread. The Maryland State Highway Administration has worked on a two-million-dollar invasive species eradication project around the Capital Beltway. Furthermore, both Virginia and Maryland have enacted laws prohibiting the spread of noxious weeds like kudzu. Connecticut is currently working on legislation that would fine planters and nurseries for selling and planting non-native and invasive species. In fact, legislation can be as efficient to address these issues as a backhoe. In Georgia, the Brookhaven City Council adopted a change to its Code of Ordinance to define invasive species. The ordinance will fine citizens if an invasive species crosses their property line and into a neighbor’s yard. The goal of the ordinance is to keep invasive species under control and improve quality of life.

While kudzu can grow a foot per day, there are ways to slow down its spread and remove it from ecosystems. Continuous mowing and weeding will weaken the plant. It is also palatable for grazing animals such as cows, goats, and horses. Over time, this can weaken the plant and eventually kill it. Humans can also eat kudzu because the leaves, flowers, and roots are all edible. While the spread of kudzu across the South can be intimidating, it has drawn awareness to this region’s biodiversity and is now one of the poster children of invasive species. It has also led authorities to begin prioritizing protected lands in once-overlooked areas such as Tennessee, Alabama, Georgia, and the Florida Panhandle.