About hemp
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A truly fascinating plant Hemp, or cannibis sativa, is a truly fascinating plant. As a natural fibre, its strength, absorption capacities and diversity of applications are second to no other. But did you also know that hemp is an important nutritional source? With an equally fascinating history, hemp also has a bright future as we look to a more sustainable and a more environmentally conscious use of resources. See the articles below for some background information about hemp; its properties, its cultivation, its history. 1. Can you get high from hemp? No! The varieties used to produce marihuana are genetically distinct from those used in the production of textiles, food and industrial products. There are a wide variety of plants in the Cannabis family. Marihuana is extracted from a variety that contains high levels of THC in the flowers and leaves. Industrial hemp has a max. THC content of 0,3%. In other words, you won’t get high from wearing a hemp T-shirt, or even from smoking it. 2. What is so ecological about hemp? Industrial hemp, or Cannabis Sativa in Latin, is an annual herbaceous plant that has been grown worldwide for centuries. Many sources even consider it to be the first cultivated crop; research dating its origin back to 4000 BC. The plant has adapted to a variety of conditions but is most suited to a moderate climate. Hemp is a remarkable plant that grows very fast (it can be harvested in just 3 months). Because it grows like a weed and has a bitter taste, it is resilient to pests and disease. It requires no irrigation, pesticide or fertiliser. In systems of crop rotation it can be used as a soil improver. As such it is a sustainable and ecological crop by its very nature, unlike conventional cotton, which requires enormous amounts of agrochemicals and relies heavily on irrigation. 3. Why was hemp originally cultivated? Historically, hemp was grown for many reasons. The seed was used for feed (both animal and human). Oil was expressed from the seeds for both cosmetic and nutritional use. The stalks were used for fibre and made into canvas, rope, bed linen, clothing and even paper. The word canvas is actually derived from the word ‘cannabis’, the Latin name for the hemp plant. Unfortunately, the application we seem most familiar with today relates to its medicinal or recreational use as a drug. 4. What role did hemp play in our history? Without hemp no long distance overseas trade would have been possible as it generated the rope and sails durable enough to survive the rough ocean crossings. Christopher Columbus would never have reached the Americas if his fleet was not rigged with hemp ropes and sails. Hemp therefore made an essential contribution to the economic boom in Europe in the 16th and 17th centuries. It is often said that most of our cultural heritage would have been lost if it was not for hemp. All the paintings of the great masters were painted on true canvas, made of hemp or sometimes linen (i.e. flax, hemp’s eco-sister). Cotton would have long disintegrated by now. The same goes for many historical books. Until the late 19th century more than three quarters of all paper was made from hemp. If historical documents, maps and books would have been printed on paper made from wood pulp, they too would have long since perished. Gütenberg printed the first bible on hemp paper. In Western Europe both flax (hemp’s eco-sister) and hemp have had similar uses. Flax can produce a finer fibre and is more suitable for finer linens, while hemp produces a rougher and stronger fibre. Many families grew hemp for its fibre, which they combed, spun into yarn and wove into sheets or towels. Servants often wore the clothes of their masters in order to soften the fabric. Hemp is indeed a fabric that ‘wears in’ rather than ‘out’ and antique hemp linens are expensive and highly sought-after items. 5. How are hemp fabrics made? The hemp stalk is first of all defoiled. The stalks are cut by predominantly mechanical means. The hemp stalks are then retted. Retting is a microbial process that loosens the stiff bast fibres. This process is necessary for producing long, fine quality fibres used for textile yarn. Retting can be done by leaving the crop on the field to rot, or immersing it in water. Water retting is more capital and labour-intensive but produces better results. However, since it had a negative impact on water plants and fish, the practice was banned in many parts of Europe. In China and Eastern Europe, where labour costs are lower, water retting is the most common method employed. It is now done in large basins rather than streams and rivers. After retting, the stalks are dried. (The landscape in many parts of rural France is still dotted with hemp ovens built for this purpose.) After drying, the stalks are scrutched and decorticated. The latter are processes which break the woody core of the stems and separate the bast fibre from the hurds. The production of hemp textiles today is very similar to traditional production methods. The only difference is related to the treatment of the raw fibre. In order to produce finer yarns and blend hemp with other fibres, the stalks are boiled in caustic soda and spun wet instead of dry. This process is called degumming and it is thanks to this innovation that hemp has become more versatile and meets 21st century consumer demands. 6. Is hemp edible? Hemp seed has proven health benefits, notably the reduction of cholesterol levels and high blood pressure. Hemp seed oil provides the ideal combination of essential polyunsaturated fatty acids which are often lacking from our typical Western diet. Polyunsaturated fatty acids (or the good fats) contribute to a healthy immune system, healthy skin, etc. The female plants produce the seeds and when grown in the right conditions, half their weight consists of seed. After the seeds are pressed for oil, the pulp is traditionally used as a highly nutritious animal feed. No need for steroids or hormones here! In many countries, hemp is consumed on a regular, if not daily basis. Only soy contains a higher amount of protein but hemp is more readily digestible. Hemp seed is fed to birds or used for fishing carp. When germinated, hemp seeds can provide a kind of ‘milk’, like soy milk, and are even richer in nutritional value. When hemp seeds are milled, they produce a flour which can be used for baking. Note that all these food products have no narcotic side effects since the hemp plant contains negligible levels of THC and because THC is in any case only present in the leaves not in the stalk or the seeds. Hemp oil also has valuable cosmetic properties. Because of the presence of gamma-linolenic acid, hemp oil is an ideal ingredient for body oils and lipid-enriched creams, which are known for their high level of penetration of the skin. 7. So why are we no longer growing hemp? If it is such a fantastic plant, why indeed did hemp disappear from our economies? To answer this question, it is important to look at both the economic and political factors. In the late 18th century, new developments in the processing of cotton made it a cheaper alternative to hemp. Another blow to the hemp industry came in the late 19th century when sailing ships were gradually replaced by steamboats. The rope and sail, previously central to the European economy, disappeared and with it, the high demand for hemp. Hemp remained as a domestic crop but was no longer cultivated commercially. While hemp lost out to cellulose based plants such as cotton and rayon, later on it had to compete with petroleum based synthetics as well. Nylon was one of the first synthetics derived from petroleum. Soon traditional ropes were replaced by synthetic alternatives, despite the fact that the inherent qualities of hemp were not surpassed by these new technologies, and that petroleum is a non-renewable resource. The only reason for replacing hemp with synthetic alternatives is the lower manufacturing costs associated with mass production. In the 1930s an increasing number of Western countries banned the cultivation of hemp, under the pretext of the presence of THC (i.e. its narcotic component). Marihuana and industrial hemp are, however, different varieties of the same plant. Nonetheless, industrial hemp suffered from the virulent anti-drug campaigns of the 1930s, it has been argued, because it was very difficult to distinguish it from medicinal hemp by sight alone. The USA banned hemp cultivation when the Marihuana Tax Act was passed in 1937. Canada followed in 1938. Interestingly enough, when supplies of abaca and jute were interrupted during World War II, the US ban on hemp was temporarily lifted (but remained under strict government control) in order to generate sufficient fibres for the US textile industry. We were surprised to learn, after a bit of research, that in Belgium, the cultivation of local hemp was already banned as early as 1921. If we put the ban in the right political and economic context of the 1930s, it is not unreasonable to suggest that other industrial interests stood to benefit from the ban on hemp. Hemp activists have described in painstaking detail how the burgeoning paper, plastic, cotton and automotive and oil industry felt threatened by new machinery developed in the 1930s for the mechanised cultivation of hemp. Rudolf Diesel, who invented the diesel engine, had actually developed it to run on vegetable (including hemp) oils. Henry Ford designed and developed a ‘plastic’ car constructed from agricultural products (including soy, cellulose and hemp fibres). However, the many ecological benefits of hemp cultivation became overshadowed by much less sustainable but economically more viable alternatives. Revolutions in chemistry made it possible to design and mass produce alternatives to many natural crops (such as rubber, sisal, hemp, …). Plastic, nylon and fossil fuel derivatives seemed then to be the materials of the future. Luckily, mentalities are changing and the virtues of traditional alternatives, like hemp, are gradually being rediscovered. Since the 1990s, farmers, environmentalists and entrepreneurs in the Western world have displayed a renewed interest in the cultivation of industrial hemp. People of vision are quickly discovering that hemp can provide an alternative to a number of unsustainable industries and help boost an ailing agricultural industry. We have slowly come to realise that a world economy reliant on petroleum is bound to cause not only an ecological disaster, but a political one as well. Petroleum is a finite resource at the centre of much of the globe’s conflicts and general instability. 8. Is there a future for hemp in Europe? Hemp is now grown as an industrial crop throughout the EU, Canada, Australia and New Zealand. Britain legalised production in 1993, Germany in 1995. European hemp is mainly used in construction and insulation materials, matting in cars and to a lesser extent for nutritional purposes. As recently as October 2005, the European Commission announced new initiatives to support the further development of the European hemp and flax industries. Hemp could take the lead in an economy set to move away from petroleum and fossil fuels towards carbohydrate (i.e. plant based) alternatives that are ecologically more sustainable. On the commercial viability of mass hemp production, sources disagree. Some argue that hemp will remain a marginal crop in Western countries given its relatively high production costs and the continued availability of cheaper alternatives or imported hemp from countries with low labour costs. However, it is important to question whether such commercial calculations take into account the environmental costs of cheaper alternatives? To what extent, furthermore, is the market prepared to pay higher prices for ecologically sound alternatives to e.g. existing insulation and construction materials, textiles etc.? These factors are more difficult to calculate and evaluate. In any case, recent years have seen a steady increase in the cultivation of industrial hemp all over Europe. Industrial hemp for textile making has not (yet) returned to Europe. So for hemp fabrics one has to turn to China where there was never a ban on hemp cultivation. We even have to acknowledge that many of the new natural fibres come from China, such as soy and bamboo. Eco die-hards have however argued against the import of hemp textiles from China. Yet Chinese imports have been at the forefront of the ‘hemp revolution’; in particular the campaign to legalise hemp production in the US. Hemp textiles, more so than industrial bi-products, can reach a broader range of consumers and thus create awareness among a larger section of the population. |
