Cotton is the most widely used plant fiber. The material is able to absorb moisture, causing you to feel cooler in the summer and warmer in the winter, because it directs moisture away from the skin.
Cotton has been used as cloth for thousands of years.
According to www.cottonsjourney.com, the cotton industry as a whole creates more than 340,000 jobs and generates over $60 billion of business in the U.S. - the greatest of any crop.
The cotton plant
Only 4 of the 39 identified species of cotton have been cultivated. They are:
Since the upland cotton plant is responsible for producing 90% of cotton, this site will focus on that particular plant.
When fully grown, the upland cotton plant will measure between 2 to 5 feet tall. Seeds are planted in the spring, and the plants germinate within 5 to 10 days, producing cotyledons, the first two leaves that are visible on the plant. These cotyledons are responsible for beginning the process of photosynthesis to help the plant develop.
After about three weeks, flower buds will appear on the plants. These are called squares. After three weeks, each opens into a flower. Three days later, after pollination, the petals begin to dry up and fall off, and the seed pod underneath develops into a boll. When the boll is mature, it will split open. The fibers, or lint, contained inside are what is harvested to later be made into fabric. When the cotton inside the bur is fully dried, it is ready to be picked.
The growth of cotton is illustrated in the following table:
Bollworms and boll weevils
Much care must be given to the cotton plant in order to ensure crop. Perhaps the most care is needed to protect the plants from being destroyed by insects. Approximately 15% of cotton in the world is destroyed by insects every year, the most damage coming from bollworms and boll weevils. Insecticides are the top source of protection that cotton farmers use to ensure survival of their crop.
Bollworms are caterpillars that feed on the buds and bolls of cotton plants. There are two different types, the pink bollworm and the corn earworm. The pink bollworm is the larvae of Pectinophora gossypiella, a type of moth. These pests mainly eat the lint, flowers, and seeds of the cotton plants, and commonly reproduce inside the buds. Up to 50% of crops can be lost in areas infested with the pink bollworms.
The corn earworm also attacks cotton bolls, but also poses a threat to other crops as well, such as corn and tomatoes. Also known as the tomato fruitworm, this insect is the larvae of the Heliothis zea moth.
Boll weevils are most commonly thought of as being the major pest of cotton plants. The insect was first found in the U.S. around 1892 in Texas, and quickly spread throughout the cotton-rich fields of the south. One of the reasons for the spreading of the cotton industry in the south was due to the pest. The United States Department of Agriculture started a campaign against this profit-threatening insect in 1978, and today boll weevils are found only in Texas, Louisiana, and Mississippi. Today, 8% of crops are lost due to this insect.
A mature boll weevil has a long snout, designed for digging deep inside the seed pod to eat the cotton fibers. Another name for the boll weevil is snout beetle.
Harvesting
Cotton is picked between 150 and 200 days after it is planted.
A mechanical cotton picker goes up and down the rows of cotton and guides the
plants through the picker head, which is surrounded by sharp spindles designed
to remove the fiber from the bur. The farmers will then press the cotton
through large machine, creating modules. Modules weigh about 20,000
pounds, and are just a way to store the cotton until it can be transported to
the cotton gin.
The Cotton Gin
In early 1793, Eli Whitney was encouraged by his employer to find a solution to the problem of separating cotton fibers from the sticky green seeds that grew in the bolls of inland plants. Within 10 days, he had built a model of what became known as the cotton gin. By April of that year, he had built an improved one.
It was a simple design: A cylinder full of jagged teeth inside a box with a hand crank. But its invention profoundly changed the course of American history by creating a revolution of cotton production in the country.
Before the invention of the cotton gin, a farmer was able to clean only about one pound of cotton per day. With the new machine, that number jumped to 50 pounds a day per farmer. Within ten years, the cotton industry grew from $150,000 to over $8 million.
While the cotton gin undoubtedly had remarkable effects on the economic status of the country, there were some negative effects of its invention. Its use caused the cotton industry to flourish in the south, ultimately requiring an increase in slavery.
Processing fiber
Ginning: The cotton fiber is removed from the cotton seed through a cotton gin. After the fibers, now called lint, are cleaned and dried, they are compressed into bales. A standard bale of cotton is 55 inches tall, 28 inches wide, 21 inches thick, and weighs about 500 pounds. Called a universal density bale, this holds enough cotton to make 325 pairs of jeans.
Classing: Experts in a government agency called the U.S. Classing Office measure the lint against a set of quality standards established by the U.S. Department of Agriculture. The standards are categorized into: (1) how white the lint is, (2) the amount of debris the bale has, and (3) the quality of the ginning process on that particular bale. Today, scientific instruments are used to detect the quality matching these characteristics.
From fiber to cloth
Blending: Workers use machines to blend the fibers from different bales into even mixtures. The fibers are cleaned, fluffed, and then formed into a loose rope called a card sliver.
Spinning: Through a series of processes, this card sliver is pulled until it becomes thin enough to twist into yarn. The ends of yarn are tied around bobbins, and strengthened with a solution of starch and gum. When dry, the yarn is ready to be woven or knitted.
History of Cotton
It is unknown exactly how old cotton is, however, bits of cotton bolls and cotton cloth found in Mexican caves have been proven to be at from at least 2900 B.C. Cotton was regularly used in present-day Mexico and Peru by 1000 A.D.
In the United States, it is believed that cotton seeds were planted in Florida in the mid-1500s, and in Virginia in the early 1600s. Cotton production quickly grew as one of the main industries in the South by the late 1700s, and the first cotton mills were built in America in the 1790s.
Between 1791 and 1860, U.S. production of cotton grew from two million pounds to a billion. By 1840, the country was producing 60% of all the cotton in the world. This caused many positive impacts on the nation's economy, as the profits from cotton paid for nearly 60% of all goods imported into the country. The crop also gained foreign investment.
The country suffered its first major economic depression in 1819, in an industry decline known as "cotton boom." Called the Panic of 1919, many farmers relied on the economic success of cotton and took out loans, in order to buy more slaves, and ultimately produce more cotton. However, by the end of the year, the price of cotton dropped nearly half from 33 cents a pound to about 16 cents a pound. This created a decline in the nation's entire economy. The same thing happened in the years following the Civil War.
It is also believed that cotton had a part in the reason for the Civil War. As mentioned earlier, the invention of the cotton gin meant an increased need for slavery in the South. However, northerners opposed slavery, and this increase in the number of slaves may have been one of the issues between the Union and the Confederacy. You can read more about slavery on the Ethical Issues page.
Linen is the fabric that comes from the fiber of the flax plant. Discovered over 3,500 years ago, it is probably the first vegetable fiber known to man. It is the strongest of the fibers that come from plants, and has almost three times the strength of cotton.
Linen fabric is very absorbent, and garments made from it tend to keep their wearers cool.
The flax plant
The flax that we derive our linen from today has been cultivated since prehistoric times. Before the development of the cotton industry, linen was the major source of fiber for clothing.
The plants grow to four feet tall, and will eventually produce blue or white flowers. After pollination, the flowers mature into bolls, or seedpod.
Harvesting and processing
The fiber is extracted from the stalk of flax. After the plants are mature, they are picked and the stems are tied together. They are then submerged in water, and then laid in the sun for several weeks, to allow bacteria to break down the substances holding the fiber together. Any remaining debris is then removed, and the fibers are separated in a process called hackling.
At the mill, the fiber is put together to form a long, continuous string, and then twisted on bobbins to produce the thread.
History of linen
Linen cloth has been found wrapped around the bodies of mummies in ancient Egyptian tombs. It was marketed at ports in the Mediterranean by Phoenician traders, and exported to Ireland and England. The first factory to manufacture linen was in Lisburn, Ireland in 1699. Today, Ireland is still the main producer of linen.
The first mill where flax was spun opened in 1787 in England, and power looms began weaving the fiber in 1812.
Ramie is similar to linen and is extracted from the stem of the ramie plant. With over 30 known varieties of the plant, the most common come from Asia. Another name for ramie is "China grass." Today it is primarily grown in China, Taiwan and India.
A perennial plant, it can be harvested as many as six times a year in desirable conditions. Each crop can live between 6 and 20 years.
Among the vegetable fibers, its fibers are reported as being the longest, averaging 125 millimeters.
Ramie is sometimes mixed with linen and wool to create different textures of those fabrics.
The ramie plant
Farmers plant pieces of roots, which in three months' time will grow into plants. The stems of the plant usually grow between three to seven feet tall. The leaves have a fuzzy white bottom, but are dark green on top.
Harvesting and processing of fiber
The best time to harvest the fiber is just before or after the blossoming of its flowers. The stems are bent in order to break the core and expose the bark.
Through the process of decortication, the bark, or cortex, is removed. Next, the bark is scraped to remove debris. Finally, it is washed and dried several times to remove gums and waxes, and the fiber is then extracted.