Flax is a plant raised for its fiber and seed. The fiber is made into linen fabric and a variety of other products, including rope, thread, high-quality paper, and composite materials. The seeds contain linseed oil, which is used primarily in the production of paints and varnishes. Linseed oil is also used in other coatings, such those that seal concrete roads against frost damage. Flax seeds and oil may also be used in cooking or taken in nutritional supplements.
There are about 230 species of flax. Only one species, Linum usitatissimum, is grown commercially. Different varieties of this species are grown for fiber and for seed.
The flax plant stands from 3 to 4 feet (0.9 to 1.2 meters) high and has either white or blue flowers. The variety grown for fiber has a slender stem that branches near the top. Seed flax is bushier than fiber flax and bears more seeds.
Flax may be attacked by a number of fungus diseases. These diseases include rust, wilt, and pasmo. Before planting flax, farmers treat the seeds with chemicals called fungicides to protect them against these diseases. Farmers also plant varieties of flax that are resistant to disease.
World production of fiber flax amounts to about 1,010,000 tons (915,000 metric tons) annually. Belgium and France are the leading countries in fiber flax production. Other leading growers include Belarus, China, and Russia. The United States and Canada do not raise fiber flax. World flaxseed production totals about 140 million bushels, or 3,920,000 tons (3,560,000 metric tons) yearly. Leading flaxseed-producing countries include Canada, China, India, Kazakhstan, Russia, and the United States.
Growing and processing fiber flax.
Fiber flax grows best in cool, moist climates with rainy summers. It is planted in the spring after the danger of frost has passed. Fiber flax is generally grown in rotation with other crops. Rotation helps reduce the effects of diseases.
Fiber flax is harvested three to four months after planting. If the plants are harvested too early, the fibers will be fine and silky, but weak. If the plants become too ripe, the fibers will be stiff and rough and difficult to spin into yarn. Farmers harvest fiber flax with a machine that pulls the stalks from the ground. On some farms, workers harvest flax by hand.
After the plants have been harvested, the flax stems are soaked in water. This process, which is called retting, rots the stalk and exposes the fibers that lie under the woody part of the stem. There are two methods of retting—dew-retting and water-retting. In dew-retting, farmers spread the flax in the field and allow the dew to rot the plants for several weeks. During the dew-retting process, the stems are turned several times and the seeds are removed. In water-retting, the seeds are removed first and the stems are then soaked in large tanks of warm water for four to eight days.
After retting, the flax stems are dried and sent through a machine that breaks them into small pieces called shives. Next, in a process called scutching, the machine separates the shives from the fibers by beating the stems with a whirling paddle or blade. In the next step, called hackling, the tow (short) and line (long) fibers are straightened and separated from each other by combing.
After combing, the fibers are baled and sent to mills for processing. The seeds that were removed from the plants are processed for oil.
Growing and processing seed flax.
Seed flax grows best in areas with cool climates and dry summers. Most seed flax is planted in early spring. In the fall, combines harvest the flax and separate the seeds from the rest of the plant. The seeds are then shipped to mills to be processed.
In the mill, the flaxseeds are ground into a meal and steamed. The oil is then removed either by squeezing the meal in a hydraulic press or by treating the meal with chemicals called solvents. Flaxseeds consist of about 40 percent oil and 60 percent water and solid matter. One bushel of seeds produces about 21/2 gallons (9.5 liters) of linseed oil. The meal that remains after processing is used as a high-protein feed for livestock. People also use ground flaxseed to make breads and other foods.
In the United States, the unused portions of the seed flax plant are processed to remove the tow fibers. The fibers are made into yarn and into paper for cigarettes, Bibles, and other products.
History.
Flax is one of the oldest cultivated crops. Flaxseeds that have been found in Syria and Turkey indicate that the plant might have been grown as early as 7000 B.C. The Egyptians began cultivating flax about 5000 B.C. By about 1000 B.C., the cultivation of flax had spread to Western Europe. In the A.D. 700’s, the areas that are now Belgium and France became leading producers of fine linen.
The first settlers in the United States and Canada planted fiber flax so they could make linen. But the invention of a cotton gin by Eli Whitney in 1793 made cotton yarn more economical than linen yarn. As a result, the two countries eventually abandoned fiber flax production. Flaxseed production declined in the United States and Canada in the 1950’s because of the increasing popularity of latex paints over oil-based paints.
