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hemp,common name for a tall annual herb (Cannabis sativa) of the family Cannabinaceae, native to Asia but now widespread because of its formerly large-scale cultivation for the bast fiber (also called hemp) and for the drugs it yields. Known and cultivated in ancient China, the plant was introduced into Europe before the Christian era. In the United States it was cultivated for fiber chiefly in the Midwest, but competition from synthetic materials led to reduced crops, and antidrug legislation led to a federal ban (1970) on hemp growing without a permit. Federal legislation in 2014 eased restrictions on the growing of industrial hemp (which has very little drug content) for research purposes, and additional legislation in 2018 permitted the regulated commercial growing of industrial hemp. The fiber, retted from the stem, was one of the most important for various kinds of cordage; it was also used in making paper, cloth (canvas and other kinds), oakum for calking ships, and other products. The male and female flowers are borne on separate plants. The chemical derived from the female flowering tops in strains bred for their drug content is used medicinally; the tops are also the source of marijuanamarijuana
drug obtained from the flowering tops, stems, and leaves of the hemp plant, Cannabis sativa (see hemp) or C. indica; the latter species can withstand colder climates.
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, resin extracted from the flower clusters and top leaves of the hemp plant, Cannabis sativa, and C. indica. Hashish, called charas in India, is the most potent grade of cannabis and is obtained from cultivated plants grown in hot, moist climates.
..... Click the link for more information. . Hemp seed is used as bird food, and the oil from the seeds is used in the manufacture of paints, varnishes, and soap and in cooking. The dried leaves are used in Asia for a beverage. The word hemp is used in combination for several other kinds of fiber plants, notably Manila hempManila hemp,
the most important of the cordage fibers. It is obtained chiefly from the Manila hemp plant (Musa textilis) of the family Musaceae (banana family). It is grown mainly in its native Philippine Islands, where it has been cultivated since the 16th cent.
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[from Sisal, former chief port of Yucatan], important cordage fiber obtained from the leaves of the sisal hemp plant, an extensively cultivated tropical agave (family Agavaceae or Liliaceae).
..... Click the link for more information. . The true hemp plant is related to the hophop,
herbaceous perennial vine of the family Moraceae (mulberry family), widely cultivated since early times for brewing purposes. The commercial hop (Humulus lupulus
..... Click the link for more information. , which is used in making beer. Hemp is classified in the division MagnoliophytaMagnoliophyta
, division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
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the coarse bast fiber from the stem of hemp plants (Cannabis sativa). The bast fibers from other plant species are also called hemp, for example, Manila hemp. Industrial hemp consists of elementary fibers measuring 14–15 mm long that are glued together. Fibers more than 700 mm long are obtained by breaking and scutching the washed and dried stems of C. sativa. Short fibers measuring 175–250 mm long are obtained from cleaning the by-products of scutching; they are also obtained from the short, matted, entangled, low-quality straw. Hemp is used to manufacture rope, string, twine, fishnets, canvas, sailcloth, and materials for furniture upholstery and drapery.