Kudzu
(Pueraria montana var. lobata)
Where it originates:
Kudzu was featured at the 1876 U.S. Centennial Exposition in Philadelphia, where the Japanese government exhibited a garden of native plants. Kudzu’s broad leaves and sweet smelling flowers made it an attractive ornamental. Its popularity as a forage and cover crop also grew well into the 20th century, with seeds being sold by mail, and one radio show host hailing it as “a miracle vine.” During the 1930s, the government planted the vine for erosion control 
in abandoned unprofitable farm fields, and in the 1940s even paid farmers $8 an acre to spread Kudzu in vacant fields. Its subsequent overgrowth and difficulty to control in the southeast deflated its popularity, and in 1953 the USDA removed Kudzu as an approved cover crop, going on to list it as a common weed in 1970.
Kudzu has been an ingredient in Asian herbal medicines for more than 2,000 years, and has been used in making baskets, paper, as well as food from its leaves or roots.
Identification:
Kudzu is a deciduous vine reaching 35-100 feet, with leaves made up of three-leaflets growing alternately on stems. Each leaflet is typically pointed at its tip and has 2-3 lobes, and may have more pronounced lobes when growing in shade. Kudzu has large tuberous roots that can reach depths of 3-16 feet, and brown hairy legume pods that appear in late fall. Clusters (racemes) of fragrant flowers bloom in mid-summer, with lavender to white colored petals.
Habitat: 
Kudzu is sometimes referred to as “the vine that ate the South.” Although versatile, it thrives in hot humid areas with average rainfall and mild winters; typical of the southeast. Infestations occur from Pennsylvania south to Florida, and as far west as the Mississippi River in Texas.
Ecological Impacts:
Although highly successful in preventing soil erosion as originally intended in the U.S., Kudzu is now estimated to impact up to 7 million acres of land. New growth can exceed one foot per day forming dense mats, usually in open fields and forest edges, and covering nearly anything in its path. It outcompetes and replaces native vegetation, and can become a serious public burden and/or hazard when it covers roadside trees, personal property, or road signs.
Control: 
Destroying roots is critical to controlling Kudzu, which can prove very difficult in areas where vines are established. Mature roots may weigh up to 100 pounds, but mowing impacted areas monthly, close to ground, and for 2-3 years can exhaust roots from fueling vine regrowth. Goats and pigs allowed to graze on Kudzu for three or more years can also control the invasive. Cutting vines and applying herbicides can also kill roots, and is most effectively done in the fall.
References:
Bergmann, Carole, and Jil Swearingen. "Kudzu." PCA's Alien Plant Working Group May 2005. Web <http://www.nps.gov/plants/alien/fact/pumo1.htm>.
Kaufman, Sylvan. Invasive Plants. 1st. Mechanicsburg, PA: Stackpole Books, 2007. 218-220. Print.
Miller, James. Nonnative InvasivePlants of Southern Forests. Asheville, NC: Southern Research Station, 2004. Print.
USFWS BayScapes Conservation Landscaping Program. Plant Invaders of Mid-Atlantic Natural Areas: Herbaceous Plants (2004). Web: <http://www.nps.gov/plants/alien/pubs/midatlantic/>.
Photo of seed pods; Ted Bodner, Southern Weed Science Society, Bugwood.org
Photo of Flower; Forest & Kim Starr, U.S. Geological Survey, Bugwood.org
Other Photos: FOR Staff