Linseed and flax

Linseed can be grown in any of the arable areas of the UK but moisture-retentive soils are preferable because of the small root system of the plant. The pH should be about 6.5. 

Because of the comparatively small area grown, pests and diseases are not generally a serious problem. Nevertheless, linseed should not be grown more often than one year in five. It is not related to atty other break crop so it can be grown in all rotations. It leaves a good seedbed for a following crop of wheat with a fine tilth and few slugs. 

Linseed varieties show continuous improvement with regard to yield, shorter and less fibrous straw, earlier and more uruform ripening, less shattering of seed and disease resistance. Current varieties include Brighton, Juliet, Batsman and Festival. They are all brown seeded varieties as opposed to yellow (HGCA UK Descriptive List for Spring Linseed). 

The seed should be treated to control damping-off and drilled 1-2 cm deep into a fine, firm and moist seedbed. For auturrm-sown crops 800-950 seeds/m should be sown in late September/early October. For spring-sown crops 600-700 seeds/m should be sown in late March/early April when soil temperatures are 6-8 °C to obtain an established population of about 400 plants/m Seed rates will range from 44-60 kg/ha because of variation in seed size between varieties. 

On fertile soils there is little response to nitrogen, phosphate and potash and at SNS index 1 the crop has a nitrogen requirement of 50-100 kg/ha, phosphate 30kg/ha and potash lOkg/ha at index 2. 

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Linseed and flax have been heavily subsidised by the Conunon Agricultural Policy (CAP), and until recently additional funding in the form of Seed Production Aid was available for certified seed production. Breeders, Pre-Basic, Basic, Cl, C2 and C3 generations are available. 

Linseed and flax are susceptible to some important seed borne diseases. No more than 5% of seeds should be infected with the following Botrytis spp., Alternaria spp., Fusarium spp., Colletotrichum Uni and Ascochyta linicola. (In the case of flax seed even more stringent conditions apply and no more than 1% of seed should be contaminated with. linicola.) Seed crops are normally sprayed with an approved fungicide before the end of flowering in order to try to achieve these standards. 

Linseed and flax are different varieties of the same plant which has been grown in this country since Roman times. Figure 14.1 shows the main difference between the two varieties. Linseed is short-strawed with capsules (bolls) to give a higher yield of seed than flax which is long-strawed and grown for its fibre. 

For fiber production, h. is cut when the male plants are in full flower and shedding pollen. The subsequent retting and scutching processes are similar to those for - linseed and - flax. H. seed contains 32% oil, 25% protein and 20% starch. Seed of h. is also useful as food. The oil (rich in C18 2 and C18 3) was used for centuries as burning oil for lamps, and its leaves and flowers were used in pharmaceutical applications. After solvent extraction, the meal may be applied as animal feed. H. fibers are also being used for the manufacturing of paper and technical filters and for the pads of brakes and clutches as well as insulation, e.g., in house construction or in automobiles. 

Froment, M.A., Smith, J.M., Turley, D., Booth, E.J., and Kightley, S.P.J. 1998. Fatty acid profiles in the seed oil of linseed and fibre flax cultivars (Linum Usitatissimum) grown in England and Scotland. Tests Agrochem. Cult. 19, 60-61. 

Flax, widely adapted to warm and cool climates, has been cultivated for centuries in various parts of the world for its stem fiber, linen cloth, and seed. Linseed is an alternative name used for flax. Crops grown for seed are termed linseed in India and in the United Kingdom and flaxseed in Canada and the United States, and flax oil or flax seed is used in many European countries. 

Most flaxseed destined for human consumption is sold in health food stores or in capsule form as a dietary supplement. The volume of organically grown flax is increasing to meet the demands of the typical health food consumer. The edible use of linseed and its oil containing health beneficial components is expected to rise in the future. 

Flax is a versatile, blue-flowered crop. It is most likely one of the oldest cultivated plants, grown either for the oil extracted from the seed or for fibre from the stem (Figure 9.1.30). There is well-documented evidence of the use of flax fibres for textiles going back to prehistoric times (see Chapter 9.6). However, in contrast to olive oil, no precise indication of the traditional use of linseed and linseed oil for nutrition or other applications may be found. Indeed, the first reliable source for utilization of linseed oil, namely for paintings, dates back to the eleventh century, when the German monk Theophilus in his Schedula diversarum artium - De diversibus artibus described the use of linseed oil for oil paints and amber varnishes. ... 

In Europe, flax was traditionally grown, processed, and manufactured locally with the Baltic States known for linseed and fiber and Northern Ireland for fine linen... 

Heijenrath R, Peijs T (1996) Natural-flber-mat reinforced thermoplastic composites based on flax flbers and polypropylene. Adv Compos Lett 5(3) 81-85 Himmelsbach D, Holser R (2008) Flax processing use of waste streams for profit. In 2008 International conference on flax and other bast plants. Saskatoon, Canada, pp 97-103 Hocking P, Randall P, Pinkerton A (1987) Mineral nutrition of linseed and fiber flax. Adv Agron 41 221-296... 

Textile workers are exposed to a number of irritants and allergens. Plant materials are commonly used, but irritant dermatitis is perhaps more common with wool, which is of animal origin, than with most plant materials. However, irritant dermatitis has been reported from persons working with linseed oil and flax [417, 418, 419, 420, 421, 422]. Exposure to textile fibers can cause irritant reactions, usually on the hands [423]. Reactions to other additives are published occasionally, e.g., a textile worker who reacted to tamarind flour... 

Linseed Oil. Flax, used for fiber and seed production and the subsequent processing of the seed into linseed oil, is grown mainly in Canada, China and India (cf. Table 14.0). Due to its high content of linolenic acid (cf. Table 14.11), the oil readily autoxidizes, one of the processes by which some bitter substances are created. Since autoxidation involving polymerization reactions proceeds rapidly, the oil solidifies Jast drying oir). Therefore, it is used as a base for oil paints, varnishes and linoleum manufacturing, etc. A comparatively negligible amount, particularly of the coldpressed oil, is utilized as an edible oil. 

Flax is one of the oldest cultivated plants with a cultural importance dating to early prehistorical periods. Linseed was first found in the former Mesopotamia. Fragments, linseed, and capsules estimated to be from the eighth millennium BC were... 

The vegetable oil obtained from flaxseed has been used for many centuries, and flax cultivation dates back to a few millennia (Henriksen and Robinson, 1996). Phylogenetic analysis has indicated that flax was initially domesticated for oil instead of fiber (Allaby et al., 2005). This ALA-rich oil has unique properties that are useful for food and non-food applications. Eood-grade oil can be obtained by cold-pressing and commercialized as flaxseed oil. Alternatively, extraction with solvents can be performed when the oil is used for nonfood industrial applications. In this case the oil is often referred to as linseed oil ... 

Soybean meal is the most frequently used source of supplemental protein in the United States (5). Cottonseed meal is another important protein supplement. Both meals are by-products from oil extraction of the seeds. Canola meal is derived from rapeseed low in emcic acid [112-86-7] and glucosinolates. Linseed (derived from flax seed), peanut, sunflower, safflower, sesame, coconut, and palm kernel meals are other sources of supplemental protein that are by-products of oil extraction (4). 

The flax fiber from the aimual plant IJnum usitatissimum (flax family, Liuaceae) has been used siuce ancient times as the fiber for linen. The plant grows iu temperate, moderately moist climates, for example, iu Belgium, France, Ireland, Italy, and Russia. The plant is also cultivated for its seed, from which linseed oil is produced. A by-product of the seed plant is the tow fiber used iu papermakiug. 

Refs. 32-37. Includes copra, cottonseed, com germ, peanuts, flax, safflower, sunflower, sesame, palm kernels, and linseed. ... 

Linolenic acid is also important industrially it is the major constituent of linseed oil (approximately 47%) which is obtained from flax. The high degree of unsaturation present in this acid makes the oil an excellent drying agent for use in paints, varnishes and inks. 

Much of the early development of science, including polymer chemistry in the USA, focused on "application" of natural materials to our needs - cotton, wood, flax, rubber, cottonseed oil, linseed oil, and wool. 

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