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Report 5 (of 5): High
Hopes - France
Introduction
Hemp or Cannabis sativa (meaning
'useful hemp') is a member of the family Cannabinaceae,
a small group of herbaceous plants. Often misunderstood
because of its association with marijuana, hemp growing
is among the world's oldest industries. Hemp differs
from marijuana because it contains very low levels
of cannabinoids (THC), the chemical known to produce
the psychoactive and intoxicating effects of marijuana.
Hemp is a unique crop because every part of it can
be used and it is an excellent renewable source of
food, fibre and energy. With a relatively short growth
time of 120 days, hemp is an efficient and economical
crop for farmers to grow.
Hemp has been grown for at least 12,000
years and has many uses. The seed is used to make
food and beauty products, the stalks produce fibre
and cellulose for everything from clothing and building
products to car parts and fuel. Unlike many plants,
it can be grown in most locations and climates with
only moderate water and fertiliser. This has made
it a valuable and environmentally friendly crop.
Hemp has been grown in France since
around 200 BC and today France is the world's largest
producer of industrial hemp, used primarily for paper-making
and for animal bedding. La Chanvriere de l'Aube (LCDA)
is a French company with a turnover of around US$10
million, which specialises in the production and processing
of hemp. It is a co-operative, working with hemp farmers
in the Champagne region of eastern France. Originally
set up to supply hemp fibre to the paper industry, it
now also uses the by-products of this process in animal
bedding and building materials.
Advantages of Hemp
Hemp is one of the most environmentally
friendly crops to be found, as it actually improves
soil condition. Hemp grows tall and thick, shading
and mulching the ground, while its deep taproots break
up and aerate the soil. This contributes to healthy
microbial life and nutrient content in the soil, and
the shading eliminates competing weeds. It is also
naturally resistant to most insects, moulds, and other
pests. Hemp requires little fertiliser and few if
any pesticides, which means it is cheap and requires
minimal effort to grow. It also means the environment
is not contaminated.
Other advantages include:
- Hemp fibres are longer, stronger,
more absorbent and more mildew-resistant than cotton.
- Hemp can be made into a variety
of fabrics, and fabrics of at least 50 per cent
hemp are more effective than other fabrics at blocking
the sun's ultraviolet rays.
- Hemp can be made into fine quality
paper. The long fibres in hemp allow such paper
to be recycled several times more than wood-based
paper and produce more pulp for paper-making.
- With a low lignin content, hemp
can be pulped using fewer chemicals than when pulping
wood. Its natural brightness means no chlorine bleach
is required, so this extremely toxic dioxin does
not need to be used.
- Hemp can displace wood fibre and
save forests for watershed, wildlife habitat and
recreation as well as for oxygen production and
carbon sequestration which reduces global warming.
The Hemp Plant
The hemp plant is harvested for its
fibres, seed, seed meal and seed oil. Due to the similar
leaf shape, hemp is frequently confused with marijuana.
Although the plants are from the same species, hemp
contains virtually no THC (delta-9-tetrahydrocannabinol),
which is the active ingredient in marijuana. Hemp
cannot be used as a drug because it produces virtually
no THC.
Characteristics
Hemp is a bast fibre plant similar
to flax, jute and ramie, meaning that it has particularly
long, slender primary fibres on the outer portion
of the stalk. An annual plant that grows from seed,
hemp can be cultivated on a range of soils, but tends
to grow best on land that is well drained, non-acidic
and rich in nitrogen. Hemp typically requires no pesticides
because is grows so quickly and attracts few pests.
In northern latitudes, hemp is usually
planted between early March and late May and averages
2-4 metres in height in four months of growth.
Hemp crops are harvested at different
times for different products. Harvesting stalks for
high quality primary fibre occurs as soon as the crop
is in flower, usually in August. Harvesting for seed
production and stalks occurs four to six weeks after
flowering, when male plants begin to shed pollen.
Primary hemp fibre
Hemp fibre possesses properties similar
to other bast and excels in fibre length, strength,
durability, absorbency, anti-mildew and anti-microbial
properties.
The valued primary fibres are contained
around the hollow, woody core of the hemp stalk. Primary
fibres are long, averaging 8 inches (20 cm) in length.
They can be spun and woven to a fine, crisp, linen-like
fabric and used for clothing, home furnishing textiles
and carpeting. Anti-mildew and anti-microbial properties
make them very suitable for sails, tarpaulins, awnings,
and floor coverings. Hemp fibre blended with wool,
cotton, linen or other fibres adds strength, durability,
absorbency and breathability, making hemp-blended
fabrics cool and comfortable to wear and touch.
Once a hemp crop has matured and been
harvested, primary fibres are separated from the stalk
through a process called retting - cut stalks
are left in the field for several weeks to allow natural
humidity and bacteria to decompose the naturally occurring
glue in the stalk that holds the fibres together.
When the retting process is complete, the fibres are
readily separated from the core, and processed for
specific products. The stalks are baled and stored
in dry, covered areas on the farms until they are
sent to be processed.
Core fibre
Core fibre is derived from the sturdy,
wood-like hollow stalk of the hemp plant. Sometimes
referred to as hurds, this fibre is up to twice
as absorbent as wood shavings, making it excellent
for animal bedding and garden mulch.
Core fibre can be blended with lime
to create a strong yet lightweight concrete or plaster.
Its high cellulose content means it can be used in the
manufacture of plastics. Like primary fibre, it is biodegradable
and possesses anti-mildew and anti-microbial properties.
Uses of Hemp
The main suppliers of hemp seed for
industrial-scale planting are the French, and many
growing, harvesting and processing technologies have
been developed in France. The French co-operative,
LCDA, invests 10 per cent of its gross profit in research
and development, as a result of which many new applications
are being promoted by the company.
Paper
Hemp paper is naturally acid-free.
The oldest printed paper in existence is 100 per cent
hemp. Hemp's cellulose level is almost three times
that of wood, so it makes superior paper and yields
four times as much pulp per acre as do trees. The
hemp paper process also uses less energy and fewer
chemicals than tree paper processing and does not
create the harmful dioxins, chloroform, or any of
the other 2,000 chlorinated organic compounds that
have been identified as by-products of the wood paper
process.
Building materials
Hemp mixed with lime has been used
as a building material in France since 500 AD. Today
it is used to make floors, walls, bricks and insulation
panels. Hemp hurds are often mixed with natural lime
and water, and sometimes plaster of Paris (pure gypsum)
or sand is added. It can be poured like cement and
hardens to become mould and insect resistant.
The material sets in a matter of hours.
It becomes a lighter, tawny colour when dry, and has
a texture similar to cork. It is many times lighter
than cement and it offers both heat and sound insulation.
The mix can be poured as a floor, or between sheets
of plywood for walls, where hemp replaces several
layers of conventional building materials.
In France LCDA have developed and
patented building materials that contain hemp: an
easy-to-install insulation material and lightweight
concrete suitable for non-load-bearing walls.
Plastics
Hemp hurds can be used as an alternative
ingredient for making different plastics because of
a naturally high level of strength. The hurds are
crushed and beaten until a fine powder is made and
then polymerised to different degrees depending on
what type of plastic is desired. The blending materials
range from polypropylene and polyethylene to polyester.
The plastics are made without using petroleum, unlike
most of today's plastics, and are biodegradable so
they can be broken down and recycled.
Automotive parts
The single largest use for hemp fibre
produced in North America is to reinforce the base
of moulded interior car parts. This technology was
pioneered in Europe and has been used by North American
car makers because of the following features:
- high tensile strength
- effective replacement for glass
fibre
- greatly reduced moulding time
- lighter finished part
- ease of processing and recycling
- consistent quality and availability
of supply.
Textiles
Hemp fibre is a popular choice for
making textiles because it is strong, comfortable
and colourfast. Hemp is a versatile fibre and can
be mixed well with cotton, silk, linen and wool. The
high cellulose content of the plant means that it
can be used to make synthetic textiles such as rayon,
too. Hemp clothing is strong and holds its shape,
stretching less than any other natural fibre. It is
durable, comfortable, and resistant to mould and ultraviolet
light.
Fuel
Hemp oil is so versatile it can be
used instead of diesel fuel. Before petroleum and
electric light bulbs, lamps burning hemp seed oil
illuminated homes around the world. One hectare (2.5
acres) of seed hemp produces about 1,000-1,500 litres
of hemp oil plus several thousand kilograms of cellulose-rich
fibre. One hectare of fibre hemp produces about 8,000-11,000
kg of dry biomass.
As a renewable resource from living
plants, hemp does not contribute to the greenhouse
effect. The growing plants absorb as much carbon dioxide
(CO2) as will later be released when oil
or other plant matter is burnt. Unlike fossil fuels
(oil, coal, gas) or nuclear fuels, hemp could supply
raw materials for thousands of years, without ever
changing our climate and without producing hazardous
waste.
Food
Hemp seed (really a tiny nut) comprises
a hull and a meaty inner core. Hemp seed is a good
source of two essential fatty acids (EFAs), Omega-3
and Omega-6, which are known to prevent or alleviate
a wide range of conditions including diabetes, heart
disease and acne (if used in the proper quantities),
and which can help build the immune system. These
EFAs cannot be produced by the body and so must be
present within the diet. Hemp seed is also a nutritious
source of vitamins and minerals including beta carotene,
vitamins A, C and E, and it does not contain any cholesterol.
Animal bedding
Currently, most of the hemp hurds
produced in the European Union are sold as bedding
for horses and other animals. Compared to cereal straw,
hemp bedding exposes sensitive animals to less dust
and fewer fungal spores and it has a much higher absorbency.
It therefore requires less maintenance and minimises
odours.
Do it yourself?
From the work done by LCDA to promote
alternative uses of hemp and the by-products of processing,
it is evident that markets can be developed to increase
the value of this hardy and environmentally useful
crop. However, while it is legal to grow hemp in France,
this does not mean that anyone can grow it. Would-be
growers must first find a buyer for their future crop;
then they must get an official agreement; finally,
they must buy certified seeds of authorised varieties
from the Hemp Growers Association. Elsewhere, it is
advisable check the local regulations before investing
in seed or processing equipment.
Glossary
Carbon sequestration is the
process of storing carbon in biomass or the soil,
underground or in oceanic ecosystems for a long period
of time. Storing carbon reduces or slows the atmospheric
build-up of carbon dioxide, a greenhouse gas. Increasing
carbon sequestration can temporarily offset greenhouse
gas emissions, which contribute to global warming.
Cellulose is a carbohydrate
that forms the main component of cell walls of plants
and wood. It is the most important constituent of
paper and cardboard, and can also be used to produce
plastics.
Websites
http://www.thehia.org/
The Hemp Industries Association represents the interests
of the hemp industry and encourages research and development
of new hemp products.
naihc.org
The North American Industrial Hemp Council promotes
the expansion of industrial hemp usage.
http://www.hemptech.org/
Hemptech is the Industrial Hemp Information Network,
a worldwide network of communications and hemp professionals
working to reintroduce industrial hemp into our economy.
It publishes books and reports, as well as providing
consulting and other information services to the growing
hemp industry.
http://www.hempfood.com/
The Hemp Food Association
http://www.globalhemp.com/
The Global Hemp website is designed to provide value
added information for those interested in learning
more about hemp. The intention of the available information
is to provide hemp related materials that are grouped
together in one place for users' convenience.
http://www.kenex.com/
Kenex works with private firms to develop quality
hemp based products for a wide array of modern uses
including: body care, cosmetics, foodstuff, building
materials, automobile interior parts, pulp and paper,
animal bedding and feed. It also supplies certified
hemp seed.
Further Reading from the ITDG Development
Bookshop
Hemp Horizons: Past, present and
future of industrial hemp
John Roulac
£14.95, 1997, Green Books, ISBN: 0930031938
This document is an output from
a project funded by the UK Department for International
Development (DFID) and the European Commission (EC)
for the benefit of developing countries. The views
expressed are not necessarily those of DFID or the
EC.
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