Hemp is one of the earliest domesticated plants known. It has been cultivated by many civilizations for over 10,000 years. Hemp use archaeologically dates back to the Neolithic Age in China, with hemp fiber imprints found on Yangshao culture pottery dating from the 5th millennium BC.
Hemp is refined into products such as hemp seed foods, hemp oil, wax, resin, rope, cloth, pulp, paper, and fuel. Hemp is used for many varieties of products including the manufacture of cordage of varying tensile strength, durable clothing and nutritional products. Hemp seeds can be eaten raw, ground into a meal and used in baking such as hemp flour, as well as hemp protein powder.
Cold pressed, unrefined hemp oil is dark to clear light green in color, with a nutty flavor. The oil is of high nutritional value because of its 3:1 ratio of omega-6 to omega-3 essential fatty acids which matches the balance required by the human body. Hemp seed oil is considered to be the best nutritional oil for health because its essential fatty acid (EFA) profile is closest to that required by the human body.
Hemp fiber has been used extensively throughout history, with production climaxing soon after being introduced to the New World. Items ranging from rope, to fabrics, to industrial materials were made from hemp fiber. Hemp was often used to make sail canvas, and the word canvas derives from cannabis.Today, a modest hemp fabric industry exists, and hemp fibers can be used in clothing. Pure hemp has a texture similar to linen.
Hemp was used extensively by the United States during World War II. Uniforms, canvas, and rope were among the main textiles created from the hemp plant at this time. Much of the hemp used was cultivated in Kentucky and the Midwest. During World War II, the U.S. produced a short 1942 film, Hemp for Victory, promoting hemp as a necessary crop to win the war.
Hemp is no longer legal to grow in the U.S. under Federal law because of its relation to marijuana, and any imported hemp products must meet a zero tolerance level. It is considered a controlled substance under the Controlled Substances Act (P.L. 91-513; 21 U.S.C. 801 et seq.). Some states have made the cultivation of industrial hemp legal, but farmers in North Dakota, Hawaii, Kentucky, Maine, Maryland, Oregon, California, Montana, West Virginia and Vermont have not yet begun to grow it because of resistance from the federal Drug Enforcement Administration. In 2013, after the legalization of marijuana in the state, several farmers in Colorado planted and harvested several acres of hemp, bringing in the first hemp crop in the United States in over half a century. Colorado, Vermont, California, and North Dakota have passed laws enabling hemp licensure. All four states are waiting for permission to grow hemp from the DEA. Currently, North Dakota representatives are pursuing legal measures to force DEA approval. Oregon has licensed industrial hemp as of August 2009. In February 2014, Congress passed an agriculture bill that eased restrictions on cultivation in 10 states.