The highly invasive kudzu vine, sometimes known as “the plant that ate the South,” may contain enough carbohydrates to make it a viable source for fuel ethanol, says a study in the journal Biomass and Biofuel. The Asian import grows more than 6.5 feet a week, cloaking many open spaces in the southern United States, especially along highways. The study found that carbohydrates, which can be broken down into ethanol by yeast, make up 68 percent of the plant’s thick roots. The vine’s density in the South suggests that kudzu could produce ethanol in quantities comparable to corn’s — an estimated 270 gallons per acre, to corn’s 210 to 320. Though it needs no care and is readily available, kudzu is far more difficult to harvest than corn, and since it is not farmed, its best use would be as a supplement to the ethanol industry, not a substitute for corn. The study estimates that kudzu could have provided 8 percent of the U.S.’s 2006 bioethanol supply.