cotton
cotton most important of the vegetable fibers, and the plant from which the fiber is harvested.
The Cotton Plant
The cotton plant belongs to the genus Gossypium of the family Malvaceae ( mallow family). It is generally a shrubby plant having broad three-lobed leaves and seeds in capsules, or bolls; each seed is surrounded with downy fiber, white or creamy in color and easily spun. The fibers flatten and twist naturally as they dry.
Cotton is of tropical origin but is most successfully cultivated in temperate climates with well-distributed rainfall. All western U.S. cotton and as much as one-third of Southern cotton, however, is grown under irrigation. In the United States nearly all commercial production comes from varieties of upland cotton ( G. hirsutum ), but small quantities are obtained from sea-island and American-Egyptian cotton (both belonging to the species G. barbadense ). G. arboreum and G. herbaceum are the chief cultivated species in Asia.
Cotton is classified in the division Magnoliophyta , class Magnoliopsida, order Malvales, family Malvaceae.
Planting and Production
Cotton is planted annually by seed in furrows; the plants are thinned and weeded during the spring growing season. Diseases and insect pests are numerous; of these the most destructive has been the boll weevil , which has caused enormous losses. Genetically altered strains of cotton are being developed that can resist infestation by some insects and damage by application of herbicides.
Mechanical harvesting is preceded by a chemical-defoliant spray to remove the leaves, leaving only the cotton bolls. In the ginhouse the cotton is separated from the seeds by a cotton gin and then baled. The usual plantation bale, weighing 500 lb (227 kg), is covered with jute and bound with iron hoops. The U.S. Dept of Agriculture has established standards for grades of cotton. The manufacture of cotton cloth involves many processes— carding , combing , and spinning —which transform raw fiber into yarn or thread strong enough for weaving.
Uses of Cotton
Innumerable commodities are made from cotton. From the lint (the fiber separated from the seed) come the major products, chiefly textile and yarn goods, cordage, automobile-tire cord, and plastic reinforcing. The linters (short, cut ends removed from the seed after ginning) are a valuable source of cellulose . Cotton hulls are used for fertilizer, fuel, and packing; fiber from the stalk is used for pressed paper and cardboard.
Production of the chief byproduct, cottonseed oil, has grown into a separate industry since its establishment in the late 19th cent. The oil content of cotton seeds is about 20%. After being freed from the linters, the seeds are shelled and then crushed and pressed or treated with solvents to obtain the crude oil. In its highly refined state, cottonseed oil is employed as salad and cooking oil, for cosmetics, and especially in the manufacture of margarine and shortenings. Paint makers use it to some extent as a semidrying oil. Less refined grades are used in the manufacture of soap, candles, detergents, artificial leather, oilcloth, and many other commodities. Cottonseed oil is increasingly important to cotton growers as cotton fiber meets competition from cheaper and stronger synthetic fibers.
History
Early History
Cotton has been spun, woven, and dyed since prehistoric times. It clothed the people of ancient India, Egypt, and China. Hundreds of years before the Christian era cotton textiles were woven in India with matchless skill, and their use spread to the Mediterranean countries. In the 1st cent. Arab traders brought fine muslin and calico to Italy and Spain. The Moors introduced the cultivation of cotton into Spain in the 9th cent. Fustians and dimities were woven there and in the 14th cent. in Venice and Milan, at first with a linen warp. Little cotton cloth was imported to England before the 15th cent., although small amounts were obtained chiefly for candlewicks. By the 17th cent. the East India Company was bringing rare fabrics from India. Native Americans skillfully spun and wove cotton into fine garments and dyed tapestries. Cotton fabrics found in Peruvian tombs are said to belong to a pre-Inca culture. In color and texture the ancient Peruvian and Mexican textiles resemble those found in Egyptian tombs.
Effect of the Cotton Gin
The invention (1793) of the cotton gin, a machine for separating seeds from fiber, and the mechanization of textile production in the Industrial Revolution enabled cotton to supersede flax and wool textiles. Cotton has played a significant role in history. Britain's need for imported cotton fiber encouraged its accession to the Monroe Doctrine; Britain's need for vast African and Indian markets for its cotton manufactures influenced its role as an imperial sea power. Beginning in North America in the Jamestown colony (1607), cotton cultivation became the basis of the one-crop, slave-labor economy of the Deep South and a principal economic cause of the Civil War. The end of slavery and the exhaustion of the soil pushed the Cotton Belt to the west.
Cotton Production Today
Today the leading cotton states are Texas, Georgia, Mississippi, Arkansas, North Carolina, and Louisiana. From the early days of the republic until recent years the United States was the world's leading cotton producer and second only to Great Britain in the manufacture of cotton goods. China now is the leading cotton-producing country, followed by the United States and India. Other important cotton producers are Pakistan, Brazil, Uzbekistan, and Turkey. China and India are the leading cotton manufacturers, followed by the United States, where cotton mills have relocated from New England to the Southern cotton-producing states. Historically, all cotton-producing nations have depended on cheap labor; although mechanical cultivating and picking devices have long been known, they have been widely used (especially in the United States) only since World War II.
Bibliography
See J. M. Munro, Cotton (2d ed. 1987); C. W. Smith and J. T. Cothren, ed., Cotton (1999).
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