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The history of Hemp (Cannabis Sativa) provides a fascinating story dating
back more than 6,000 years. China has an unbroken history of Hemp textile
production dating from before 4,500 BC with the spread to Asia around 1,000
BC and reaching Europe around 800 BC.
It became an important crop of enormous economic and social value supplying
much of the world's need for food and bast fibre.
Sailing ships became dependent on Canvas (from the word cannabis), Hemp rope
and oakum due to it being 3 times stronger than Cotton and rot resistant in
salt water. In 1175 Hemp was taxed and in 1535 Henry VIII passed an act
compelling all landowners to sow 1/4 of an acre, or be fined. During this period Hemp was a
major crop and up to the 1920's 80% of clothing was made from Hemp textiles.
The biggest decline for the U.K. fibres came from Cotton and with the advent
of the 'Spinning Jenny' in the 1870's Cotton prices fell dramatically.
A further crisis for Hemp arose in America during the 1930's due to
propaganda created by companies with vested interest from the new petroleum
based synthetic textile companies and the large and powerful newspaper /
lumber barons who saw Hemp as the biggest threat to their businesses (they
created the confusion between Cannabis Indica (marijuana) and Cannabis
Sativa (Hemp).
Traditionally, Hemp was processed by hand which was very labour intensive
and costly, not lending itself towards modern commercial production. In 1917
American George W. Schlichten patented a new machine for separating the
fibre from the internal woody core ('Hurds') reducing labour costs by a
factor of 100 and increasing fibre yield by a factor of 60. Mr Schlichten
and his machines disappeared, not surprisingly!
During World War II the supplies of Hemp from the East were being cut off so
American farmers were encouraged to grow Hemp for military use (webbing,
canvas etc.) under the banner of "Hemp For Victory". After the war, licenses
were subsequently revoked, at a similar time to the last Hemp crops being
grown in the U.K.
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In 1971 Cannabis became caught up in the politics of the Opiate laws and
became classed as a restricted plant under the misuse of drugs act.
In the 1990's new agricultural initiatives were put forward in Europe
towards sustainable alternative crops to alleviate the massive surpluses of
food being produced. Farmers in the U.K. felt disadvantaged and lobbied the
Home Office into harmonizing legislation across the EC. In 1992 / 93 the
first licenses were granted for growing Hemp of the low THC varieties (THC
is the narcotic substance found in the plants leaves) under the ruling that
Hemp is grown for "special purposes" or "in the public interest".
At present, approximately 2,500 hectares are being grown. To put this into
perspective, in 1992 600,000 hectares of land were put to set-aside. This
area of Hemp would give a yield of over 6 million tons of biomass and
120,000 tons of fibre. 4 billion pounds worth of tree pulp is imported into
the U.K. every year leaving a trade deficit of £2.3 billion (1992 Figures).
Cotton and Bast fibres such as Jute and Sisal are all imported. The use of
fibre grown on subsidised U.K. set aside land could easily resolve this
trade deficit. Hemp is now once again, after being demonised through
propaganda and prohibition, set to make a comeback in the light of awareness
of our current non-sustainable future and continued damage to the
environment. Unfortunately in uncertain political times for the Government
and the vested interest of companies that sustain them, visions and benefits
are put aside as to pander to the whims of the status quo and short-term
non-sustainable future. Agenda 21, due to be published in June may show a
way forward for industry and mankind. The future of Hemp is only restricted
by an awareness of it's true potential as the environmental benefits of Hemp
are outstanding.
Hemp is said historically to have over 25,000 diverse uses ranging from
paints, printing inks, varnishes, paper, bibles, Government documents, bank
notes, food, textiles (the original 'Levi's' jeans were made from Hemp
cloth), canvas (Hemp canvases were used by the great masters) and building
materials. With modern technical developments uses have increased to
composite boards, motor vehicle brake and clutch pads, plastics, fuels,
bio-diesel and Eco-solid fuel. In fact anything that can be made from a
hydrocarbon (fossil fuel) can be made from a carbohydrate (William Hayle,
1930).
The plant is a prolific and sustainable environmental crop growing at any
latitude from Norway to the Equator. Currently most raw materials are
imported from China and Hungary.
The processes for extraction of fibres are firstly retting which is the
natural breakdown of the lignin in the bark of the plant to release the
fibres, which usually takes two weeks. After this the plant stem is
mechanically broken to extract the coarse long fibres. These are then
scutched to remove the woody core hurds and other dusts and foreign matters.
The coarse fibres are then hackled to remove any debris and carded ready for
spinning. Fibres can now be spun to NM 15 count and by blending are suitable
for knits. The physical advantages of Hemp fibre are its strength and
ability to withstand temperatures of 600oc without denigration. The fibres
also block more of the UV rays, an important factor in the changing ozone
layer, and are more insulative than cotton.
Due to the decline of the textile trade, especially regarding long fibres,
the Hemp Union Ltd. feel the way forward is in using current short fibre
spinning technology. New processing experiments in Europe are now able to
produce fibres comparable with cotton.
The main current market places that have Hemp awareness are America and
Germany, also Spain, Austria, Switzerland, Australia, Canada, France and
Norway. It would appear that the growth rate of the market place in some of
these countries is about 90%. The whole project has to be market led and
proactive in creating public awareness.
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