Hemp

This article is about the cultivation and uses of industrial hemp, not its psychoactive cousin Cannabis. For the biology of the plant, see Cannabis. For other senses of the word hemp, see Hemp (disambiguation) & Hemp (cannabis oglalas) .

U.S. 'Marihuana' production permit. In the USA, hemp cultivation is legally prohibited, but during World War II farmers were encouraged to grow hemp for cordage, to replace manila hemp previously obtained from Japanese-controlled areas. The US government produced a film explaining the uses of hemp called Hemp for Victory.

Hemp (from Old English hænep, see cannabis (etymology)) is the common name for plants of the genus Cannabis, although the term is often used to refer only to Cannabis strains cultivated for industrial (non-drug) use. Hemp is cultivated virtually everywhere in the world except for the United States, and is growing immensely. For example, Canadian Hempseed exports surged 300% last year, according to VoteHemp.

Industrial hemp has thousands of uses, from paper to textiles to biodegradable plastics to health food to fuel. It is also runs parallel with the "Green Future" objectives that are becoming increasingly popular. Hemp requires little to no pesticides, replenishes soil with nutrients and nitrogen, and converts CO2 to Oxygen very well, considering how fast it grows. Furthermore, Hemp could be used to replace many potentially harmful products, such as tree paper (the process of which uses bleaches and other toxic chemicals, apart from contributing to deforestation), cosmetics (which often contain synthetic oils that can clog pores and provide little nutritional content for the skin), plastics (which are petroleum based and cannot decompose), and more.

Licenses for hemp cultivation are issued in the European Union and Canada. In the United Kingdom, these licenses are issued by the Home Office under the Misuse of Drugs Act 1971. When grown for non-drug purposes hemp is often called industrial hemp, and a common product is fiber for use in a wide variety of products. Feral hemp or ditch weed is usually a naturalized fiber or oilseed strain of Cannabis that have escaped from cultivation and are self-seeding.

Cannabis sativa L. subsp. sativa var. sativa is the variety grown for industrial use in Europe, Canada, and elsewhere, while C. sativa subsp. indica generally has poor fiber quality and is primarily used for production of recreational and medicinal drugs. A major difference is the amount of Δ⁹-tetrahydrocannabinol (THC) secreted in a resinous mixture by epidermal hairs called glandular trichomes. Strains of Cannabis approved for industrial hemp production in Europe and elsewhere produce only minute amounts of this psychoactive drug. Some botanists use a different taxonomic classification to circumscribe the various taxa within the genus Cannabis.

Uses

An industrial hemp crop growing in Canterbury, New Zealand

Hemp is used for a wide variety of purposes, including the manufacture of cordage of varying tensile strength, clothing, and nutritional products. The bast fibers are can be used in 100% hemp products, but are commonly blended with fabrics such as linen, cotton or silk, for apparel and furnishings, most commonly a 55/45 Hemp/Cotton blend. The inner two fibers of hemp are more woody, and are more often used in non-woven items and other industrial applications, such as mulch, animal bedding and litter. The oil from the fruits ("seeds") dries on exposure to air (similar to linseed oil) and is sometimes used in the manufacture of oil-based paints, in creams as a moisturising agent, for cooking, and in plastics. Hemp seeds are often added to wild bird seed mix. In Europe and China, hemp fibers are increasingly used to strengthen cement, and in other composite materials for many construction and manufacturing applications. Mercedes-Benz uses a "biocomposite" composed principally of hemp fiber for the manufacture of interior panels in some of its automobiles. Hemp cultivation in the United States is suppressed by laws supported by drug enforcement agencies, for fear that high THC plants will be grown amidst the low THC plants used for hemp production. Efforts are underway to change these laws, allowing American farmers to compete in the growing markets for this crop. As of 2006, China produces roughly 40% of the world's hemp fiber and has been producing much of the world's Cannabis crop through out much of history.

Food

Hemp seeds are comparable to sunflower seeds, and may be used for food and milk, tea, and for baking, like sesame seeds. Products range from cereals to frozen waffles. A few companies produce value added hemp seed items that include the seed oils, whole hemp grain (which is sterilized as per international law), hulled hemp seed (the whole seed without the mineral rich outer shell), hemp flour, hemp cake (a by-product of pressing the seed for oil) and hemp protein powder. Hemp is also used in some organic cereals. Hemp seed can also be used to make a non-dairy "milk" somewhat similar to soy and nut milks, as well as non-dairy hemp "ice cream." Within the UK, the Department for Environment, Food and Rural Affairs (Defra) treats hemp as purely a non-food crop. Seed can and does appear on the UK market as a legal food product although cultivation licences are not available for this purpose. In North America, hemp seed food products are sold in small volume, typically in health food stores or by mail order.

Nutrition

Typical nutritional analysis of shelled hempseed

Calories/100 g	567
Protein (Nx5.46)	30.6%
Fat	47.2%
Saturated fat	5.2%
Monounsaturated fat	5.8%
Polyunsaturated fat	36.2%
Carbohydrate	10.9%
Oleic 18:1 (Omega-9)	5.8%
Linoleic 18:2 (Omega-6)	27.56%
Linolenic 18:3 (Omega-3)	8.68%
Cholesterol	0.0%
Total dietary fiber	6.0%
Vitamin A (B-Carotene)	4 IU/100 g
Thiamine (Vit B1)	1.38 mg/100 g
Riboflavin (Vit B2)	0.33 mg/100 g
Vitamin B6	0.12 mg/100 g
Vitamin C	1.0 mg/100 g
Vitamin D	2277.5 IU/100 g Template:Fact
Vitamin E	8.96 IU/100 g
Sodium	9.0 mg/100 g
Calcium	74.0 mg/100 g
Iron	4.7 mg/100 g

30–35% of the weight of hempseed is oil containing 80% unsaturated essential fatty acids (EFAs), linoleic acid (LA, 55%) and alpha-linolenic acid (ALA, 21–25%). These are not manufactured by the human body and must be supplied by food. The proportions of linoleic acid and alpha-linolenic acid in hempseed oil meet human requirements for EFAs, including gamma-linoleic acid (GLA). Unlike flax oil and others, hempseed oil can be used continuously without developing a deficiency or other imbalance of EFAs. Unfortunately the unsaturated fat makes the oil rancid quickly, unless it is stored in dark coloured bottles or mixed with chemical preservatives. This makes hemp oil difficult to transport or store. The high unsaturated fat content also makes the oil unsuitable for frying. This severely limits hemp oil's potential on the food market, although some marketing potential exists as a nutritional supplement.

Hemp seed also contains 20% complete and highly-digestible protein, 1/3 as edestin protein and 2/3 as albumins. Its high quality amino acid composition is closer to "complete" sources of proteins (meat, milk, eggs) than all other oil seeds except soy.

The ALA contained in plant seed oils by itself is sufficient for nutrition, as the human body is capable of converting it into other fatty acids. But this conversion process is inefficient, and the broader spectrum of omega-3 fatty acids obtained from oily fish is easier for the body to immediately use. See Oily fish#Oils from fish or plants as a source of Omega-3 fatty acids.

Medicine

Main article: Medicinal cannabis

Fiber

The fiber is one of the most valuable parts of the hemp plant. It is commonly called "bast", meaning it grows as a stalk from the ground. Hemp fibers can be 3 to 15 feet long, running the length of the plant. Depending on the processing used to remove the fiber from the stem, the hemp naturally may be creamy white, brown, gray, black or green.

The use of hemp for fiber production has declined sharply over the last two centuries, but before the industrial revolution, hemp was a popular fiber because it is strong and grows quickly; it produces 250% more fiber than cotton and 600% more fiber than flax when grown on the same land.Template:Fact Hemp has been used to make paper. The Declaration of Independence was printed on hemp paper. It was used to make canvas, and the word canvas itself derives from cannabis.[12][13] Hemp was very popular as it had many uses. However, as other coarse-fibre plants were more widely grown, hemp fibre was replaced in most roles. Manila yielded better rope. Burlap, made from jute, took over the sacking market. The paper industry began using wood pulp. The carpet industry switched over to wool, sisal, and jute, then nylon. Netting and webbing applications were taken over by cotton and synthetics. The world hemp paper pulp production was believed to be around 120,000 tons per year in 1991 which was about 0.05 % of the world's annual pulp production volume.

In 1916, US Department of Agriculture chief scientists Lyster H. Dewe, and Jason L. Merrill created paper made from hemp pulp, which they concluded was "favorable in comparison with those used with pulp wood." Jack Herer, in the book "The Emperor Wears No Clothes" summarized the findings of Bulletin No. 404:

“

In 1916, USDA Bulletin No. 404, reported that one acre of cannabis hemp, in annual rotation over a 20-year period, would produce as much pulp for paper as 4.1 acres of trees being cut down over the same 20-year period. This process would use only 1/4 to 1/7 as much polluting sulfur-based acid chemicals to break down the glue-like lignin that binds the fibers of the pulp, or even none at all using soda ash. The problem of dioxin contamination of rivers is avoided in the hemp paper making process, which does not need to use chlorine bleach (as the wood pulp paper making process requires) but instead safely substitutes hydrogen peroxide in the bleaching process. ... If the new (1916) hemp pulp paper process were legal today, it would soon replace about 70% of all wood pulp paper, including computer printout paper, corrugated boxes and paper bags.

”

It is easy to show that the quotation from 1916 above was a very bad prediction. Pulp from wood is today produced in large quantities without chlorine, pollutions from sulfur is reduced with more than 95% with today's technology and hemp is of no significance as raw material for paper in for example the European union where cultivation of industrial hemp is legal. The long-term price for pulpwood has been low compared with any alternative except recycled paper. More about pulp technology in Bleaching of wood pulp

The decision of the United States Congress to pass the 1937 Marijuana Tax Act was based in part on testimony derived from articles in newspapers owned by William Randolph Hearst, who had significant financial interests in the timber industry, which manufactured his newsprint. The background material also included that from 1880 to 1933 the hemp grown in the United States had declined from 15,000 to 1,200 acres, and that the price of line hemp had dropped from $12.50 per pound in 1914 to $9.00 per pound in 1933. As a result of the act, the production and use of hemp discontinued.

Characteristics of hemp fibre are its superior strength and durability, resistance to ultraviolet light and mold, comfort and good absorbency (8%)Template:Fact. Hemp rope is notorious for breaking due to rot as the capillary effect of the rope-woven fibres tended to hold liquid at the interior, while seemingly dry from the outside. Hemp rope used in the age of sailing-ships was protected by tarring, a labor-intensive process and also the reason for the Jack Tar nickname for sailors. Hemp rope was phased out when Manila, which does not require tarring, became available.

There is a niche market for hemp paper, but the cost of hemp pulp is approximately six times that of wood pulp, mostly due to the small size and outdated equipment of the few hemp processing plants in the Western world. Hemp pulp is bleached with hydrogen peroxide. Hydrogen peroxide can also be used for wood pulp. Kenaf is another fast-growing plant which can be used as a replacement for wood pulp. Kenaf paper has been produced in commercial quantities.

A modest hemp industry exists. Recent developments in processing have made it possible to soften up coarse fibres to a wearable level.

Harvesting

Hemp stem.

Smallholder plots are usually harvested by hand. The plants are cut at 2 to 3 cm above the soil and left on the ground to dry. Mechanical harvesting is now common, using specially adapted cutter-binders or simpler cutters.

The cut hemp is laid in swathes to dry for up to four days. This was traditionally followed by retting, either water retting (the bundled hemp floats in water) or dew retting (the hemp remains on the ground and is affected by the moisture in dew moisture, and by molds and bacterial action). Modern processes use steam and machinery to separate the fibre, a process known as thermo-mechanical pulping.

Fuel

Biofuels such as biodiesel and alcohol fuel can be made from the oils in hemp seeds and stalks, and the fermentation of the plant as a whole, respectively, but the energy from hemp is low compared with the volume of the harvested hemp.

Henry Ford grew marijuana on his estate after 1937Template:Fact, possibly to prove the cheapness of methanol production at Iron Mountain. He made plastic cars with wheat straw, hemp and sisal. (Popular Mechanics, Dec. 1941, "Pinch Hitters for Defense.") In 1892, Rudolph Diesel invented the diesel engine, which he intended to fuel "by a variety of fuels, especially vegetable and seed oils."

Cultivation

Hemp being harvested

Millennia of selective breeding have resulted in varieties that look quite different. Also, breeding since circa 1930 has focused quite specifically on producing strains which would perform very poorly as sources of drug material. Hemp grown for fibre is planted closely, resulting in tall, slender plants with long fibres. Ideally, according to Defra in 2004 the herb should be harvested before it flowers. This early cropping is done because fibre quality declines if flowering is allowed and, incidentally, this cropping also pre-empts the herb's maturity as a potential source of drug material. However, in these strains of industrial hemp the tetrahydrocannabinol (THC) content would have been very low regardless.

The name Cannabis is the genus and was the name favoured by the 19th century medical practitioners who helped to introduce the herb's drug potential to modern English-speaking consciousness. Cannabis for non-drug purposes (especially ropes and textiles) was then already well known as hemp.

The name "marijuana" is Spanish in origin and associated almost exclusively with the herb's drug potential. That marijuana is now well known in English as a name for drug material is due largely to the efforts of US drug prohibitionists during the 1920s and 1930s.

Varieties

There are broadly three groups of Cannabis varieties being cultivated today:

• Varieties primarily cultivated for their fibre, characterized by long stems and little branching, extreme red, yellow, blue of purple coloration, or thickness of stem and solid core called hemp cannabis oglalas & more generally called industrial hemp
• Varieties grown for seed from which hemp oil is extracted
• Varieties grown for medicinal, spiritual development 1, 2, 3, 4, 5, 6, 7 or recreational purposes.

A nominal if not legal distinction is often made between hemp, with concentrations of the psychoactive chemical THC far too low to be useful as a drug, and Cannabis used for medical, recreational, or spiritual purposes.

Diseases

Main article: List of hemp diseases

Historical cultivation

While the fibre has been grown for millennia in Asia and the Middle East, commercial production of hemp in the West took off in the eighteenth century. Due to colonial and naval expansion of the era, economies needed large quantities of hemp for rope and oakum. The endless European Wars, and ever expanding naval fleets, all used the material. To this end, the young Republic of America became a large hemp producer. The Gulf and Carolina states had very large hemp industries. In fact the market was second only to cotton fibre. Machinery was invented in the United States for producing hemp fibre. An unpleasant task performed by prison labour was the manufacture of rope and boat caulking. Before the age of nylon rope, hemp rope had a short lifetime and was ever in need of replacement. In the 19th century it was cultivated by binders.

'"From the 1881 Household Cyclopedia':

The soils most suited to the culture of this plant are those of the deep, black, putrid vegetable kind, that are low, and rather inclined to moisture, and those of the deep mellow, loamy, or sandy descriptions. The quantity of produce is generally much greater on the former than on the latter; but it is said to be greatly inferior in quality. It may, however, be grown with success on lands of a less rich and fertile kind by proper care and attention in their culture and preparation.

In order to render the grounds proper for the reception of the crop, they should be reduced into a fine mellow state of mould, and be perfectly cleared from weeds, by repeated ploughings. When it succeeds grain crops, the work is mostly accomplished by three ploughings, and as many harrowings: the first being given immediately after the preceding crop is removed, the second early in the spring, and the last, or seed earth, just before the seed is to be put in. In the last ploughing, well rotted manure, in the proportion of fifteen or twenty, or good compost, in the quantity of twenty-five or thirty-three horse-cart loads, should be turned into the land; as without this it is seldom that good crops can be produced. The surface of the ground being left perfectly flat, and as free from furrows as possible; as by these means the moisture is more effectually retained, and the growth of the plants more fully promoted.

It is of much importance in the cultivation of hemp crops that the seed be new, and of a good quality, which may in some measure be known by its feeling heavy in the hand, and being of a bright shining color.

The proportion of seed that is most commonly employed, is from two to three bushels [per acre], according to the quality of the land; but, as the crops are greatly injured by the plants standing too closely together, two bushels, or two bushels and a half may be a more advantageous quantity.

As the hemp plant is extremely tender in its early growth, care should be taken not to put the seed into the ground at so early a period, as that it may be liable to be injured by the effects of frost; nor to protract the sowing to so late a season as that the quality of the produce may be effected. The best season, on the drier sorts of land in the southern districts, is as soon as possible after the frosts are over in April; and, on the same descriptions of soil, in the more northern ones, towards the close of the same month or early in the ensuing one.

The most general method of putting crops of this sort into the soil is the broadcast, the seed being dispersed over the surface of the land in as even a manner as possible, and afterwards covered in by means of a very light harrowing. In many cases, however, especially when the crops are to stand for seed, the drill method in rows, at small distances, might be had recourse to with advantage; as, in this way, the early growth of the plants would be more effectually promoted, and the land be kept in a more clean and perfect state of mould, which are circumstances of importance in such crops. In whatever method the seed is put in, care must constantly be taken to keep the birds from it for some time afterwards.

This sort of crop is frequently cultivated on the same piece of ground for a great number of years, without any other kind intervening; but, in such cases, manure must be applied with almost every crop, in pretty large proportions, to prevent the exhaustion that must otherwise take place. It may be sown after most sorts of grain crops, especially where the land possesses sufficient fertility, and is in a proper state of tillage.

Thick stands of fibre hemp compete well with weeds.

As hemp, from its tall growth and thick foliage, soon covers the surface of the land, and prevents the rising of weeds, little attention is necessary after the seed has been put into the ground, especially where the broadcast method of sowing is practised; but, when put in by the drill machine, a hoeing or two may be had recourse to with advantage in the early growth of the crop.

In the culture of this plant, it is particularly necessary that the same piece of land grows both male and female, or what is sometimes denominated simple hemp. The latter kind contains the seed.

When the grain is ripe (which is known by its becoming of a whitish-yellow color, and a few of the leaves beginning to drop from the stems); this happens commonly about thirteen or fourteen weeks from the period of its being sown, according as the season may be dry or wet (the first sort being mostly ripe some weeks before the latter), the next operation is that of taking it from the ground; which is effected by pulling it up by the roots, in small parcels at a time, by the hand, taking care to shake off the mould well from them before the handsful are laid down. In some districts, the whole crop is pulled together, without any distinction being made between the different kinds of hemp; while, in others, it is the practice to separate and pull them at different times, according to their ripeness. The latter is obviously the better practice; as by pulling a large proportion of the crop before it is in a proper state of maturity, the quantity of produce must not only be considerably lessened, but its quality greatly injured by being rendered less durable.

After being thus pulled, it is tied up in small parcels, or what are sometimes termed baits.

Where crops of this kind are intended for seeding, they should be suffered to stand till the seed becomes in a perfect state of maturity, which is easily known by the appearance of it on inspection. The stems are then pulled and bound up, as in the other case, the bundles being set up in the same manner as grain, until the seed becomes so dry and firm as to shed freely. It is then either immediately threshed out upon large cloths for the purpose in the field, or taken home to have the operation afterwards performed.

The hemp, as soon as pulled, is tied up in small bundles, frequently at both ends.

It is then conveyed to pits, or ponds of stagnant water, about six or eight feet in depth, such as have a clayey soil being in general preferred, and deposited in beds, according to their size, and depth, the small bundles being laid both in a straight direction and crosswise of each other, so as to bind perfectly together; the whole, being loaded with timber, or other materials, so as to keep the beds of hemp just below the surface of the water.

It is not usual to water more than four or five times in the same pit, until it has been filled with water. Where the ponds are not sufficiently large to contain the whole of the produce at once, it is the practice to pull the hemp only as it can be admitted into them, it being thought disadvantageous to leave the hemp upon the ground after being pulled. It is left in these pits four, five, or six days, or even more, according to the warmth of the season and the judgment of the operator, on his examining whether the hempy material readily separates from the reed or stem; and then taken up and conveyed to a pasture field which is clean and even, the bundles being loosened and spread out thinly, stem by stem, turning it every second or third day, especially in damp weather, to prevent its being injured by worms or other insects. It should remain in this situation for two, three, four, or more weeks, according to circumstances, and be then collected together when in a perfectly dry state, tied up into large bundles, and placed in some secure building until an opportunity is afforded for breaking it, in order to separate the hemp. By this means the process of grassing is not only shortened, but the more expensive ones of breaking, scutching, and bleaching the yarn, rendered less violent and troublesome.

After the hemp has been removed from the field it is in a state to be broken and swingled, operations that are mostly performed by common laborers, by means of machinery for the purpose, the produce being tied up in stones. The refuse collected in the latter process is denominated sheaves, and is in some districts employed for the purposes of fuel. After having undergone these different operations, it is ready for the purposes of the manufacturer.

History

Hemp use dates back to the Stone Age, with hemp fibre imprints found in pottery shards in China and Taiwan over 10,000 years old. These ancient Asians also used the same fibres to make clothes, shoes, ropes, and an early form of paper.

Hemp cloth was more common than linen until the mid 14th centuryTemplate:Fact. The use of hemp as a cloth was centered largely in the countryside, with higher quality textiles being available in the towns. Virtually every small town had access to a hemp fieldTemplate:Fact .

In late medieval Germany and Italy, hemp was employed in cooked dishes, as filing in pies and tortes, or boiled in a soup.

The traditional European hemp was by tradition and due to its low narcotic effect not used as a drug in Europe. It was cultivated for its fibers and for example used by Christopher Columbus for ropes on his ships.

Thomas Jefferson drafted the United States Declaration of Independence on hemp paper.

In the Napoleonic era, many military uniforms were made of hempTemplate:Fact . While hemp linens were coarser than those made of flax, the added strength and durability of hemp, as well as the lower cost, meant that hemp uniforms were preferred.

Hemp was used extensively by the United States during WWII. Uniforms, canvas, and rope were among the main textiles created from the hemp plant at this time. Much of the hemp used was planted in the Midwest and Kentucky. Historically, hemp production made up a significant portion of Kentucky's economy and many slave plantations located there focused on producing hemp.

By the early twentieth century, the advent of the steam engine and the diesel engine ended the reign of the sailing ship. The advent of iron and steel for cable and ships' hulls further eliminated natural fibers in marine use, although hemp had long since fallen out of favour in the sailing industry in prefernce to manilla hemp. The invention of artificial fibers in the late thirties by DuPont further put strain on the market.

Major hemp producing countries

Typical Japanese Shinto shrine with paper streamers & rope made out of unprocessed hemp fibre.

From the 1950s to the 1980s the Soviet Union was the world's largest producer (3,000 km² in 1970). The main production areas were in Ukraine, the Kursk and Orel regions of Russia, and near the Polish border.

Other important producing countries were China, North Korea, Hungary, the former Yugoslavia, Romania, Poland, France and Italy.

In Japan, hemp was historically used as paper and a fiber crop; it was restricted as a narcotic drug in 1948. The ban on marijuana imposed by the US authorities was alien to Japanese culture, as cannabis had been freely used in Japan for over 10,000 years.Template:Fact There is archaeological evidence that cannabis was used for clothing and the seeds were eaten in Japan right back to the Jōmon period (10,000 to 300 BC). Many Kimono designs portray hemp, or "Asa" (Template:Lang-ja), as a beautiful plant.

Canada, the United Kingdom, and Germany all resumed commercial production in the 1990s. British production is mostly used as bedding for horses; other uses are under development. The largest outlet for German fibre is composite automotive panels. Companies in Canada, UK, US and Germany among many others process hemp seed into a growing range of food products and cosmetics; many traditional growing countries still continue to produce textile grade fibre.

Hemp is illegal to freely grow in the US and several other countries because the plant is related to marijuana. In such countries, hemp is imported from China and the Philippines. The US is the only industrialized country where hemp is illegal to grow.

Future of hemp

In the last decade, hemp was widely promoted as a crop for the future. This is stimulated by new technologies which make hemp suitable for industrial paper manufacturing, as a renewable energy source (biofuel), and the use of hemp derivatives as replacements for petrochemical products.

In America, pro-hemp laws have been passed in a dozen states, five in North Dakota (ND) alone. Under the new ND law, farmers no longer need permission from the DEA to grow industrial hemp, which now is distinguished from "marijuana".[14] ND was very close to its first growing season, but the DEA delayed the applications too late to begin the season.

Hemp Plastic is a new technology based on 20-100% hemp fiber-based plastics that can be molded or injection molded. The use of fiber-reinforced composites and other natural plastics are expected to become more popular as oil prices rise and the world becomes more environmentally aware.

The increased demand for health food has stimulated the trade of shelled hemp seed, hemp protein powder and hemp oil as well as finished and ready-to-eat food products (waffles, granola bars, ice cream, and milk for example) using these derivatives as ingredients. The use of hemp oil in the manufacture of body care products has also increased.

THC in hemp

Hemp contains delta-9-tetrahydrocannabinol (THC), which is the psychoactive ingredient found in hashish and marijuana. While THC is present in all Cannabis plant varieties to some extent, industrial Hemp does not contain an amount to produce any intoxicating effect, even in significant quantities. In varieties grown for use as a drug, where males are removed in order to prevent fertilization, THC levels can reach as high as 20-30% in the unfertilized females which are given ample room to flower. In hemp varieties grown for seed or fibre use, the plants are grown very closely together and a very dense biomass product is obtained, rich in oil from the seeds and fibre from the stalks and low in THC content. EU and Canadian regulations limit THC content to 0.3% in industrial hemp.

On October 9, 2001, the US Drug Enforcement Administration (DEA) ruled that even traces of THC in products intended for food use would be illegal as of February 6, 2002. This Interpretive Rule would have ruled out the production or use of hempseed or hempseed oil in food use in the USA, but after the Hemp Industries Association (HIA) filed suit the rule was stayed by the United States Court of Appeals for the Ninth Circuit on March 7, 2002. On March 21, 2003, the DEA issued a nearly identical Final Rule which was also stayed by the Ninth Circuit Court of Appeals on April 16, 2003. On February 6, 2004, the Ninth Circuit Court of Appeals issued a unanimous decision in favor of the HIA in which Judge Betty Fletcher wrote, "[T]hey (DEA) cannot regulate naturally-occurring THC not contained within or derived from marijuana-i.e. non-psychoactive hemp is not included in Schedule I. The DEA has no authority to regulate drugs that are not scheduled, and it has not followed procedures required to schedule a substance. The DEA's definition of "THC" contravenes the unambiguously expressed intent of Congress in the Controlled Substances Act (CSA) and cannot be upheld". On September 28, 2004, the HIA claimed victory after DEA declined to appeal to the Supreme Court of the United States the ruling from the Ninth Circuit Court of Appeals protecting the sale of hemp-containing foods. Industrial hemp remains legal for import and sale in the U.S., but U.S. farmers still are not permitted to grow it.

Strong opposition to trace amounts of THC, a chemical shown by scientific research to be less addictive and less harmful than nicotine or alcohol, leads some of its critics, like Jack Herer in The Emperor Wears No Clothes, to charge ulterior motives such as protection of the synthetic-fibre, wood pulp, petrochemical, and pharmochemical industries. The US government's position has not been completely constant, as shown by the wide-spread cultivation of industrial hemp in Kentucky and Wisconsin during World War II. Critics of the HIA, however, argue that the necessities of the war and the unavailability of adequate synthetic substitutes outweighed the (unfounded) social, health, and public safety risks of producing hemp.

The presence of (some) THC in hemp varieties and the fear that fields with hemp can hide cultivation of cannabis with more THC has hampered the development of hemp in many countries, most notably, the United States. However, this has been proven as a fallacy by marijuana growers and botanists alike.

Marijuana is often female only, and kept completely isolated from any males, to keep the THC production up and seed production low. There are specially developed strains that require a very specific growing operation, and there is much care put into increasing THC production. Hiding marijuana in a hempfield would create a variety of problems. One is, the dense Hemp would most likely "choke out" the marijuana, taking valuable and necessary nutrients and sunlight that the marijuana needs to produce THC. Even more, the male hemp plants would fertilize the marijuana plants, which would have several side effects. First, the marijuana would produce seeds, quickly lowering it's value. Energy growing seeds quickly diminishes THC content. More importantly, the fertilization essentially crossbreeds the Hemp and marijuana (only in the THC potent Females). While the Hemp will not produce any more THC, the marijuana, once "tainted" by the Hemp, will produce significantly less THC, depending on how long and how close the contact is with the Hemp.

If marijuana was successfully hidden and grown in a hempfield, the resulting plant matter would be of very little street value. It would be full of seeds and stems (because of fertilization), be malnutritioned (because Hemp, like a strong weed, sucks up nutrients and grows taller, taking the available sun), and above all, have a very low THC content, making it undesirable to even the indiscriminate marijuana smokers. There is a consensus between experts and marijuana growers alike; the risk to reward ratio is far out of proportion for it to even be considered.

Gallery of images

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External links

General

• Hemp.com Information portal and store
• Hemp.co.uk Information since 1996
• Zelfoaustralia.com Zelfo is 100% 'hemp plastic'
• hempdidge.com 100% hemp musical instruments
• Essential oil of Cannabis sativa L. strains, by Vito Mediavilla and Simon Steinemann
• Plant Cultures: hemp botany, history, uses
• Read Congressional Research Service (CRS) Reports regarding Hemp as an Agricultural Commodity
• The Emperor Wears No Clothes
• Hemp For Victory American Department of Agriculture video
• State Taxation of Harvested Marijuana Exhibit
• Famous users of industrial hemp.

Hemp industry

• Hemp Bio-fuels in New Zealand
• Canadian Hemp Trade Alliance
• Hemp Industries Association
• The Hemp Report (subscription)
• Hemp For Victory
• IndustrialHemp.net
• Industrial Hemp Directory
• International Hemp Association
• National Non Food Crop Centre
• Open Directory Project - Business/Agriculture and Forestry/Industrial Hemp
• Ontario Hemp Alliance
• Saskatchewan Hemp Association
• Vote Hemp
• Montana Hemp Council