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What is hemp?

The word "hemp" comes from the Old English word for the cannabis plant.

Hemp plants are among the most hardy of all plants; they can survive on a clear-cut mountainside and can help start an ecosystem's healing process going again. They require, as all plants do, sunlight, soil, and moisture. Their harvest cycle can be anywhere from 3 months to a year.

Hemp plants naturally grow to anywhere from about one to three meters in height. They have strong root systems, sufficient for use as an effective guard against soil erosion. They are "strong growers", i.e. they grow quickly and use a lot of stored energy in doing so, and thus have a natural resistance to weeds; they overpower them. For this reason, they requirelittle or no herbicides. They also have few animal or insect enemies.

Hemp has two well-known distinctive properties. Firstly, it contains an excellent source of fibrous materials. The stalk of any plant will contain structural fibres; this is what keeps the plant standing straight and pointing away from the Earth, towards the light of the sun. Generally,the larger the plant, the more weight to be held upright, the stronger thefibres are required to be. This can be seen, in an excessive way, in thedifference between a daisy and a redwood.

The fact that hemp is basically a large bush means that it needs a strong structural canestalk. In fact, the hemp plant produces some of the strongest natural fibres known to man. These fibres can be extracted via machinery and used in the production of nearly anything that requires structural fibres. The fibres also contain less lignin than wood fibre, requiring less chemical processing.

Secondly, the flowering "top" of the plant naturally contains small amounts of tetrahydrocannabanol (THC). This is a relatively safe psychoactive substance which, when present in the bloodstream of human and other mammal brains, triggers a "cannabanoid" neuroreceptor, causing various sensual and sensory effects. It appears then that either THC isvery similar to a neurochemical produced by the human body itself, tostimulate these receptors in what could be described as an emotional process;or, there may be an ancient symbiotic benefit associated with THC and thehuman brain which co-evolved in both man and plant.

Less well known properties include the nutritive properties of the hemp seed. Rich in essential fats and oils, the seeds could provide a nutritional boost to a food-culture which mistakenly percieves all fat as a badthing; which is more and more lacking in the important fats oils; and which isbeing inundated with downright dangerous fats, oils, and synthetic substitutes. The seeds can be ground into a flour, not unlike other strictly cereal crops like wheat or oats.

What can be made out of hemp?

Paper
Producing paper from hemp would alleviate the burden placed upon the environment by the forest industry. Not only can hemp produce more paper per crop area, it also grows in a much shorter cycle and thus can be harvested much more often than a tree crop. 1 acre of hemp produces as much paper as 4.1 acres of trees. 75-90% of all paper in the world was made with hemp fibre until 1883: books, maps, money, records, etc. including the Gutenburg Bible (15th C.)
Canvas
Hemp was responsible for 90% of ship's sails before the 19th century. Hemp canvas was also the art canvas of choice of many of the greatest painters, including Rembrandt and Van Gogh.
Rope
70-90% of all rope, twine and cordage was made from Hemp until 1937. It is now largely made from petrochemical fibres such as nylon.
Textiles
Hemp is softer than cotton, warmer than cotton, more water-absorbant than cotton, has 3 times the tensile strength of cotton, and is many times more durable than cotton. It must be noted that ~50% of chemicals used in American agriculture today are used in cotton growing. Hemp growing requires no chemicals and it has few weed or insect enemies. Hemp was, until the 1820's, often used to make all kinds of textiles and fabrics for clothes, tents, linens, rugs, drapes, quilts, bedsheets, towels, diapers, flags, etc.
Biomass
Biomass is the use of dead organic materials - which could easily be supplied en masse by crops of hemp - as an alcohol-based fuel. Henry Ford designed a biomass car which was in itself largely organic (wood, hemp plastic, etc.) Burning petrochemicals releases both carbon dioxide (CO2) and poisonous corbon monoxide (CO) from the chemicals; burning biomass releases only the CO2 which the plants breathed in during their life.
Paint and Varnish
In 1935, 58,000 tons of hemp seeds were used in America just for the manufacture of paint and varnish from their oil. After that year, a certain chemical company began manufacturing most of the synthetic petrochemical oils that have since been in use, since hemp was soon after prohibited.
Building Materials
As newer polymer-glue technologies have developed, building materials can now be constructed by reconstituing individual fibre strands, orienting them to the same direction, sandwiching layers together and gluing them: examples include OSB (Oriented strand board) and Engineered Lumber. These fibre strands could just as easily come from Hemp or straw as trees.
Plastic
The process of making some plastics involve polymerizing cellulose, of which hemp is an excellent source. These could be used in place of petroleum-based plastics, such as PVC.

Hemp Paper

"There are 2.4 million boxes of official government documents tucked away in federal buildings across [Canada]. Each box weighs between 11 and 13 kilograms [around 25lbs] and holds one cubic foot of paper."

--- Winnipeg Free Press, "Offices die, paper lives on... and on", Jan 13 1996The progression in the early 90's towards a "paperless office" anda "paperless society" was mostly an illusion; paper has remained one ofthe most readable and efficient physical media for still text and pictures.

But the drain on the forests has not decreased, and North America is stillusing a lot of paper in it's offices. Paper need not be made from wood!It has been made from papyrus, rice, straw, and hemp among many other plants.

Hemp paper is strong and durable and requires less chemical processingthan wood pulp paper.

Engineered Lumber and Oriented Strand Board

In Europe during World War II, due to bombings of steel factories, theprocess of engineering lumber from strands and chips of wood wasdeveloped.

Engineered lumber has many times the structural strength of timber,has a smaller mass-to-structural-strength ratio than wooden members andrequires less wood to produce.

To engineer lumber, a mills start with thin sheets, strips, strands,and chips of wood veneer or another source of cellulose. This practiceis much less wasteful than cutting rectangular sticks out of cylindricallogs. The fibrous sheets and strips are sandwiched together with asort of polymer glue. The glue holding these fibres together givesthe engineered lumber it's strength. This allows floor joists to beincredibly thin I-beams yet support twice as much weight as standardstructural lumber without squeaking.

Similar to structural members, strands and chips canbe compressed into a board shape to engineer sheathing, usually termedOriented Strand Board. The oriented fibre strands create a solid sheetwhich can be applied to framing to create a wall surface, and can then becovered in siding or painted.

Scrap wood veneer is currently the most common component inengineered lumber and oriented strand board, although that need notbe the case. Flaxstraw, kenaf, hemp, and ramie all provide suitablecellulose fibres for these applications.

Insulation

"[In Europe,] a new building insulation made from hemp core, Isochanvre,is catching on. By a process first discovered by the Egyptians 4,000 yearsago, the hemp core is transformed into a mineral material. The productprovides sound and thermal insulation, and is waterproof, rotproof, andfire-proof."

- The Watershed Sentinel, June/July 1995

Plastics and other Polymers

Plastics, and many other synthetic materials, are formed by a process calledpolymerization, which is a means of makinglong chains of atoms form a molecule with unusual properties. These materialsare called

polymers.

Polymers are formed out of monomers, which are derived from a chemicalfeedstock, usually petroleum-based. This may be replaced by a renewable cellulosefeedstock such as hemp fibre.

Reference source for this page and other pages at Cat's-Eye Technologies, unless specifically noted in the text, is the wholly remarkable book

The Emperor Wears No Clothes

1995 Edition. By Jack Herer. Editors: Chris Conrad, Lynn & Judy Osburn.

H.E.M.P. (Help End Marijuana Prohibition)
5632 Van Nuys Blvd., #210, Van Nuys, CA 91401
(818)377-5886
ISBN 1-878125-00-1.

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