Kudzu is almost always referred to as a noxious, invasive weed. However, as has been pointed out, kudzu was originally brought to America as a crop. While it may grow a little too fast for comfort, it still does have significant uses:
- Food. The Japanese have consumed kudzu as food for thousands of years. It's not always tasty, but it has saved many from famine. Every part of the kudzu plant is useful for food. Powdered kudzu root is a starchy flour much like corn starch and can be used to make soups and puddings. Kudzu leaf is a leafy green like spinach or kale, and is sturdy enough to use like grape leaves. Kudzu blossoms can be used to make a deep maroon tea, though many find it bitter. In Japan, a kudzu-flavored tofu is a delicacy. Kudzu recipes are readily found online.
- Livestock feed. Livestock that are allowed to graze (free-range) will consume the kudzu leaf, and pigs will eat the starchy root. According to the US Department of Agriculture, the kudzu plant is slightly more nutritious than alfafa, making it a fairly cheap, quickly-replenishing source of food for cattle and other livestock.
- Alternative Fuel. Using a yeast that can ferment both xylose and glucose (by way of enzymatic conversion of starches), kudzu could be a very rapid source of ethanol.
- Medicine. Kudzu may be a powerful remedy for alcoholism, according to traditional Chinese medicine and backed up by a Harvard medical study by Dr. Bert L. Vallee and Dr. Wing-Ming Keung in 1993. The study involved hamsters that preferred alcohol to water, who were then injected them with an isoflavonoid compound derived from kudzu root extract. Most of the hamsters cut their alcohol intake in half or better, a superior result compared to many other pharmaceutical treatments for the disease. The study also noted that the kudzu root extract also resulted in reduced effects of hangovers, as well as improving the motor skills of the drunk hamsters.
Source: http://www.pnas.org/cgi/reprint/90/21/10008.pdf for the information about the alcoholism study.