The name of both a plant and the fibre it produces. Cotton is related to mallows, hollyhocks, and hibiscus, all members of the mallow family (Malvaceae). They include annuals and perennials, many shrubby and growing up to 6 m/20 ft high, though usually much less in cultivation. The leaves are palmately lobed; the funnel-shaped flowers, up to 5 cm/2 in diameter, with creamy-white, yellow, or reddish petals, are visited by bees and hummingbirds. The ovoid seed pods (bolls) burst when ripe to reveal tightly packed seeds covered with creamy-white fibres which contain 8790% cellulose. Cotton is graded according to the length (staple) and appearance of the fibres. The highest quality are long staple, such as Sea Island cotton (Gossypium barbadense), with lustrous fibres 2·56·5 cm/12½ in long, used for yarns and fine fabrics. Medium staple, such as American upland cotton (Gossypium hirsutum) has fibres 1·33·3 cm/½1¼ in long, used for a variety of fabrics. Short staple cottons have coarse fibres 12 cm/0·40·8 in long, used for cheap fabrics, blankets, and carpets. The bolls are picked when ripe, either by hand or by machine after the plants have been chemically defoliated, causing all the bolls to open simultaneously. Four processes then follow: removal of the seeds (ginning), cleaning and separating (carding), stretching (drawing), and finally spinning into yarn. One of the most useful natural fibres, cotton is a crop of worldwide importance; major producing countries include the USA, Russia, China, India, Egypt, and Turkey. (Genus: Gossypium, c.20 species. Family: Malvaceae.)
Cotton is a soft fiber that grows around the seeds of the cotton plant (Gossypium spp.), a shrub native to the tropical and subtropical regions of Africa and the Americas.
Cotton fiber (once processed to remove seeds and traces of wax, protein, etc.) consists of nearly pure cellulose, a natural polymer. Cotton production is very efficient, in the sense that, ten percent or less of the weight is lost in subsequent processing to convert the raw cotton bolls into pure fiber.
Cultivation
Successful cultivation of cotton requires a long growing season, plenty of sunshine and water during the period of growth, and dry weather for harvest.
Cotton plant
Cotton fiber originates from the cotton plant, an important crop in tropical climates and warm temperate climates.
History
Cotton has been used to make very fine lightweight cloth in areas with tropical climates for millennia. Evidence has been found of cotton in Mexican caves (cotton cloth and fragments of bloody fibre interwoven with feathers and fur) which dated back to approximately 7,000 years ago. There is clear archaeological evidence that people in India and South America domesticated different species of cotton independently thousands of years ago.
The earliest reference to cotton was in India, where cotton cultivation began in the Old World. Cotton has been grown in India for more than 6,000 years since the pre-Harappan period, and it is later referred to in the Rig-Veda, composed around 1500 BC. 106)
In Peru, cotton was the backbone of the development of coastal cultures such as the Moche and Nazca.
During the late mediaeval period, cotton became known as an imported fibre in northern Europe, without any knowledge of what it came from other than that it was a plant; This was largely due to the East India Company's de-industrialization of India, which forced the closing of cotton processing and manufacturing workshops in India, to ensure that Indian markets supplied only raw materials and were obliged to purchase manufactured textiles from Britain.
The advent of the Industrial Revolution in Britain provided a great boost to cotton manufacture, as textiles emerged as Britain's leading export. The invention of the spinning jenny in 1764 and Richard Arkwright's spinning frame in 1769 enabled British weavers to produce cotton yarn and cloth at much higher rates. Improving technology and increasing control of world markets allowed British traders to develop a commercial chain in which raw cotton fibres were (at first) purchased from colonial plantations, processed into cotton cloth in the mills of Lancashire, and then re-exported on British ships to captive colonial markets in West Africa, India, and China (via Shanghai and Hong Kong).
By the 1840s, India was no longer capable of supplying the vast quantities of cotton fibres needed by mechanised British factories, while shipping bulky, low-price cotton from India to Britain was time-consuming and expensive. This, coupled with the emergence of American cotton as a superior type (due to the stronger fibres of American plants) encouraged British traders to purchase cotton from slave plantations in the United States and the Caribbean. Due to the enormous quantities of raw cotton required to make cheap bulk exports, British industrialists quickly abandoned expensive raw cotton produced in India in favour of mass-produced cotton from the southern United States, which was much cheaper as it was produced by unpaid slaves.
During the American Civil War, American cotton exports slumped due to a Union blockade on Southern ports, prompting the main purchasers of cotton, Britain and France, to turn to Egyptian cotton. After the American Civil War ended in 1865, British and French traders abandoned Egyptian cotton and returned to cheap American exports, sending Egypt into a deficit spiral that led to the country declaring bankruptcy in 1876, a key factor behind Egypt's annexation by the British Empire in 1882.
During this time cotton cultivation in British Empire , especially India, greatly increased to replace the lost production of the American South which had been the main supplier to the English mills. Through tariffs and other restrictions the English government discouraged the production of cotton cloth in India; This cotton is shipped on British bottoms, a three weeks journey across the Indian Ocean, down the Red Sea, across the Mediterranean, through Gibraltar, across the Bay of Biscay and the Atlantic Ocean to London. (Fisher 1932 pp 154-156)
In the United States, cotton remained a key crop in the southern economy after emancipation and the end of the civil war in 1865. Cotton plantations required vast labour forces to hand-pick cotton fibres, and it was not until the 1950s that reliable harvesting machinery was introduced into the South (prior to this, cotton-harvesting machinery had been too clumsy to pick cotton without shredding the fibres). During the early twentieth century, employment in the cotton industry fell as machines began to replace labourers, and as the South's rural labour force dwindled during the First and Second World Wars. Today, cotton remains a major export of the southern United States, and a majority of the world's annual cotton crop is of the long-staple American variety.
chemicals such as fertilizers and insecticides, although a very small number of farmers are moving towards an organic model of production and organic cotton products are now available for purchase at limited locations.
Historically, in North America, one of the most economically destructive pests in cotton production has been the boll weevil.
Most cotton in the United States, Europe and Australia is harvested mechanically, either by a cotton picker, a machine that removes the cotton from the boll without damaging the cotton plant, or by a cotton stripper which strips the entire boll off the plant. Cotton strippers are generally used in regions where it is too windy to grow picker varieties of cotton and generally used after application of a defoliant or natural defoliation occurring after a freeze.
The logistics of cotton harvesting and processing have been improved by the development of the cotton module builder, a machine that compresses harvested cotton into a large block, which is then covered with a tarp and temporarily stored at the edge of the field.
Research and promotion
Beginning as a self-help program in the mid-1960s, the Cotton Research & Promotion Program was organized by U.S. Upland cotton producers in response to cotton's steady decline in market share.
Administered by the Cotton Board and conducted by Cotton Incorporated, the Cotton Research & Promotion Program is the program that is continuously working to increase the demand for and profitability of cotton through various research and promotion activities.
Uses
Cotton is used to make a number of textile products. These include terrycloth, used to make highly absorbent bath towels and robes, denim, used to make blue jeans, chambray, popularly used in the manufacture of blue work shirts (from which we get the term "blue-collar"), along with corduroy, seersucker, and cotton twill. While many fabrics are made completely of cotton, some materials blend cotton with other fibers, including rayon and synthetic fibers such as polyester.
In addition to the textile industry, cotton is used in fishnets, coffee filters, tents and in bookbinding.
The cottonseed which remains after the cotton is ginned is used to produce cottonseed oil, which after refining can be consumed by humans like any other vegetable oil.
Cotton linters are fine, silky fibers which adhere to the seeds of the cotton plant after ginning.
Pests
The greatest ecological threat to cotton plants is the boll weevil. During the late nineteenth century and early twentieth century, boll weevil infestations caused significant damage to annual cotton crops in the southern United States, resulting in frequent economic depressions in rural areas.
Fair trade
Cotton is an enormously important commodity throughout the world.
This has led to an international dispute:
On 27 September 2002 Brazil requested consultations with the US regarding prohibited and actionable subsidies provided to US producers, users and/or exporters of upland cotton, as well as legislation, regulations, statutory instruments and amendments thereto providing such subsidies (including export credits), grants, and any other assistance to the US producers, users and exporters of upland cotton. The international production and trade situation has led to 'fair trade' cotton clothing or footwear (Veja Sneakers) being available in some countries. 77°F (25°C) Optimum travel temperature - 68°F (20°C) Autoignition temperature (for oily cotton) - 248°F (120°C) Glow temperature - 401°F (205°C) Fire point - 410°F (210°C) Autoignition temperature - 765°F (407°C)
Cotton dries out, becomes hard and brittle and loses all elasticity at temperatures above 25°C.
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