Hemp is a tall, annual plant, Cannabis sativa, family Cannabaceae, cultivated for its fibers and seed oil, and for the drugs marijuana and hashish. Native to Asia, the plant is now widely cultivated for its fiber in Russia, the Central Asian republics, Serbia, and Italy, and for drug products principally in the Middle East, India, Mexico, and North Africa. Hemp also refers to the plants abaca (Manila hemp), sisal, and sunn, all of which have similar fibers.(1)
The strong, flat bast fibers of the hemp plant range in length from 1-2.5 M (3-8 ft). The fibers are removed from the stem by a process similar to that used for flax. Because hemp fibers are less elastic and more difficult to bleach than flax, they are used only in rough fabrics such as sacking. They resist water better than other natural vegetable fibers and were once widely used for ropes, hammocks, and cables, but they have largely been replaced by synthetic fibers.(1)

Hemp Fiber Processing
Hemp
Last Update: Sunday, March 9, 2003

Note: (1)  Information from 1998 Grolier Multimedia Encyclopedia