A History of Hemp

Hemp, or industrial hemp typically found in the northern hemisphere, is a variety of the Cannabis sativa plant species that is grown specifically for the industrial uses of its derived products. It is one of the fastest growing plants and was one of the first plants to be spun into usable fiber 10,000 years ago. It can be refined into a variety of commercial items including paper, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food and animal feed.

Although cannabis as a drug and industrial hemp both derive from the species Cannabis sativa and contain the psychoactive component tetrahydrocannabinol (THC), they are distinct strains with unique hytochemical compositions and uses. Hemp has lower concentrations of THC and higher concentrations of cannabidiol (CBD), which eliminates its psychoactive effects. The legality of industrialhemp varies widely between countries. Some governments regulate theconcentration of THC and permit only hemp that is bred with anespecially low THC content.

Etymology

The etymology is uncertain but there appears to be no common Proto-Indo-European source for the various forms of the word; theGreek term kánnabis is the oldest attested form, which may have been borrowed from an earlier Scythian or Thracian word. Then it appears to have been borrowed into Latin, and separately into Slavic and from there into Baltic, Finnish, and Germanic languages. Following Grimm’slaw, the “k” would have changed to “h” with the first Germanic sound shift, after which it may have been adapted into the Old English form, hænep. However, this theory assumes that hemp was not widely spread among different societies until after it was already being used as a psychoactive drug, which Adams and Mallory(1997) believe to be unlikely based on archaeological evidence. Barber (1991) however, argued that the spread of the name “kannabis” was due to its historically more recent drug use, starting from the south, around Iran, whereas non-THC varieties of hemp are older and prehistoric. Another possible source of origin is Assyrian qunnabu, which was the name for a source of oil, fiber, and medicine in the1st millennium BC.

Uses

Hemp seed

Hemp is used to make a variety of commercial and industrial products including rope, textiles, clothing, shoes, food, paper, bio-plastics, insulation, and biofuel. The bast fibres can be used to make textiles that are 100% hemp, but they are commonly blended with other fibres, such as flax, cotton or silk, as well as virgin and recycled polyester, to make woven fabrics for apparel and furnishings. The inner two fibres of the plant are more woody and typically have industrial applications, such as mulch, animal bedding and litter. When oxidized (often erroneously referred to as”drying”), hemp oil from the seeds becomes solid and can be used in the manufacture of oil-based paints, in creams as a moisturising agent, for cooking, and in plastics. Hemp seeds have been used in bird feed mix as well. A survey in 2003 showed that more than 95% of hemp seed sold in the European Union was used in animal and bird feed.

Food

Hemp seeds can be eaten raw, ground into hemp meal, sprouted or made into dried sprout powder. The leaves of the hemp plant can be consumed raw in salads. Hemp seeds can also be made into a liquid and used for baking or for beverages such as hemp milk, hemp juice, and tea. Hemp oil is cold-pressed from the seed and is high in unsaturated fatty acids.

In the UK, the Department for Environment, Food and Rural Affairs treats hemp as a purely non-food crop, but with proper licensing and proof of less than 0.2% THC concentration, hemp seeds can be imported for sowing or for sale as a food or food ingredient. In the U.S., imported hemp can be used legally in food products and, as of 2000, was typically sold in health food stores or through mail order.

Nutrition

A 100-gram portion of hulled hemp seeds supplies 586 calories. They contain 5% water, 5% carbohydrates, 49% total fat, and 31%protein. Hemp seeds are notable in providing 64% of the Daily Value(DV) of protein per 100-gram serving. Hemp seeds are a rich source of dietary fibre (20% DV), B vitamins, and the dietary minerals manganese (362% DV), phosphorus (236% DV), magnesium (197% DV), zinc(104% DV), and iron (61% DV). About 73% of the energy in hempseed is in the form of fats and essential fatty acids, mainly polyunsaturated fatty acids, linoleic, oleic, and alpha-linolenic acids.

Hempseed’s amino acid profile is comparable to other sources of protein such as meat, milk, eggs and soy. Protein digestibility-corrected amino acid scores (PDCAAS), which attempt to measure the degree to which a food for humans is a “complete protein”, were 0.49–0.53 for whole hemp seed, 0.46–0.51 for hempseed meal, and 0.63–0.66 for hulled hempseed.

Storage

Hemp oil oxidises and turns rancid within a short period of time if not stored properly; its shelf life is extended when it is stored in a dark airtight container and refrigerated. Both light and heat can degrade hemp oil.

Fibre

Hemp fibre has been used extensively throughout history, with production climaxing soon after being introduced to the New World. For centuries, items ranging from rope to fabrics, to industrial materials were made from hemp fibre. Hemp was also commonly used to make sail canvas. The word “canvas” is derived from the word cannabis. Pure hemp has a texture similar to linen. Because of its versatility for use in a variety of products, today hemp is used in a number of consumer goods, including clothing, shoes, accessories, dog collars, and homewares.

Building material

Main article: hempcrete

Concrete-like blocks made with hemp and lime have been used as an insulating material for construction. Such blocks are not strong enough to be used for structural elements; they must be supported by a brick, wood, or steel frame. However, hemp fibres are extremely strong durable and have been shown to be usable as a replacement for wood for many jobs, including creating very durable and breathable homes. The most common use of hemp lime in building is by casting the hemp and lime mix while wet around a timber frame with temporary shuttering, and tamping the mix to form a firm mass; after the removal of the temporary shuttering, the solidified hemp mix is then ready to be plastered with a lime plaster.

The first example of the use of hempcrete was in 1986 in France with the renovation of the Maison de la Turquie in Nogent-sur– Seineby the innovator Charles Rasetti. In the UK hemp lime was first used in 2000 for the construction of two test dwellings in Haverhill. Designed by Modece Architects, who pioneered hemp’s use in UK construction, the hemp houses were monitored in comparison with other standard dwellings by BRE. Completed in 2009, the Renewable House is one of the most technologically advanced made from hemp-based materials. The first US home made of hemp-based materials was completed in August 2010 in Asheville, North Carolina.

A panellized system of hemp-lime panels for use in building construction is currently under test in a European Union-funded research collaboration led by the University of Bath. The panels are being designed to assure high-quality construction, rapid on-site erection, optimal hydrothermal performance from day one, and energy-and resource-efficient buildings. The 36-month-long work programme aims to refine product and manufacturing protocols, produce data for certification and marketing, warranty, insurance cover, and availability of finance. It also includes the development of markets in Britain, France, and Spain.

Hemp is used as an internal plaster and is a mixture of hemp hurd (shive) mixed with larger proportions of a lime-based binder. Hemp plaster has insulation qualities.

Plastic and composite materials

A mixture of fibreglass, hemp fibre, kenaf, and flax has been used since 2002 to make composite panels for automobiles. The choice of which bast fibre to use is primarily based on cost and availability. Various car makers are beginning to use hemp in their cars, including Audi, BMW, Ford, GM, Chrysler, Honda, Iveco, Lotus, Mercedes, Mitsubishi, Porsche, Saturn, Volkswagen and Volvo. For example, the Lotus Eco Elise and the Mercedes C-Class both contain hemp (up to 20kg in each car in the case of the latter).

Paper

Hemp paper varieties consisting exclusively or to a large extent from pulp obtained from fibres of industrial hemp. The products are mainly speciality papers such as cigarette paper, banknotes and technical filter papers. Compared to wood pulp, hemp pulp offers a four to five times longer fibre, a significantly lower lignin fraction as well as a higher tear resistance and tensile strength. However, production costs are about four times higher than for paper from wood, so hemp paper could not be used for mass applications as printing, writing and packaging paper.

Jewellery

Hemp and bead Jewellery

Hemp jewellery is the product of knotting hemp twine through the practice of macramé. Hemp jewellery includes bracelets, necklaces, anklets, rings, watches and other adornments. Some jewellery features beads made from crystals, glass, stone, wood and bones. The hemp twine varies in thickness and comes in a variety of colours. There are many different stitches used to create hemp jewellery, however, the half knot and full knot stitches are most common.

Shoes

In recent years, hemp has been growing in popularity as a material used in shoes. Today you can find boots, athletic shoes, sandals and dress shoes that are made with 100% hemp fibre, or textiles that blend hemp fibres with materials such as cotton, jute, virgin polyester, and recycled polyester. The strength of hemp fibres make sit an ideal material for shoes because it’s durable. In addition ,it’s breathable and naturally antimicrobial, so it doesn’t hold on to odors. Because hemp can be grown sustainably, shoes, clothing, and accessories made with hemp are representative of the sustainable fashion movement.

Hemp rope

Hemp rope was used in the age of sailing ships, though the rope had to be protected by tarring, since hemp rope has a propensity for breaking from rot, as the capillary effect of the rope-woven fibrest ended to hold liquid at the interior, while seeming dry from the outside. Tarring was a labour-intensive process, and earned sailors the nickname “Jack Tar”. Hemp rope was phased out whenManila, which does not require tarring, became widely available. Manila is sometimes referred to as Manila hemp, but is not related to hemp; it is abacá, a species of banana.

Animal bedding

Hemp shives are the core of the stem, hemp hurds are broken parts of the core. In the EU, they are used for animal bedding (horses, for instance), or for horticultural mulch. Industrial hemp is much more profitable if both fibres and shives (or even seeds) can be used.

Water and soil purification

Hemp can be used as a “mop crop” to clear impurities out of waste water, such as sewage effluent, excessive phosphorus from chicken litter, or other unwanted substances or chemicals. Additionally, hemp is being used to clean contaminants at the Chernobyl nuclear disaster site, by way of a process which is known as phytoremediation—the process of clearing radioisotopes and a variety of other toxins from the soil, water, and air.

Weed control

Hemp crops are tall, have thick foliage, and can be planted densely, and thus can be grown as a smother crop to kill tough weeds. Using hemp this way can help farmers avoid the use of herbicides, gain organic certification, and gain the benefits of crop rotation. However, due to the plant’s rapid and dense growth characteristics, some jurisdictions consider hemp a prohibited and noxious weed, much like Scotch Broom.

Biofuels

Biodiesel can be made from the oils in hemp seeds and stalks; this product is sometimes called “hempoline“. Alcohol fuel(ethanol or, less commonly, methanol) can be made by fermenting the whole plant.

Filtered hemp oil can be used directly to power diesel engines. In1892, Rudolf Diesel invented the diesel engine, which he intended to power “by a variety of fuels, especially vegetable and seed oils, which earlier were used for oil lamps, i.e. the Argand lamp.”

Production of vehicle fuel from hemp is very small. Commercial biodiesel and biogas is typically produced from cereals, coconuts, palm seeds and cheaper raw materials like garbage, wastewater, dead plant and animal material, animal faeces and kitchen waste.

Processing

Traditionally, hemp stalks would be water-retted first before the fibres were beaten off the inner hurd by hand, a process known as scutching. As mechanical technology evolved, separating the fibre from the core was accomplished by crushing rollers and brush rollers that would produce a nearly clean fibre. After the Marijuana Tax Act was implemented in 1938, the technology for separating the fibres from the core remained “frozen in time”.

Only in 1997, did Ireland, parts of the Commonwealth and other countries begin to legally grow industrial hemp again.

Cultivation

Hemp is usually planted between March and May in the northern hemisphere, between September and November in the southern hemisphere. It matures in about three to four months.

Millennia of selective breeding have resulted in varieties that display a wide range of traits; e.g. suited for a particular environments/latitudes, producing different ratios and compositions of terpenoids and cannabinoids (CBD, THC, CBG, CBC, CBN…etc.), fibre quality, oil/seed yield etc. Hemp grown for fibre is planted closely, resulting in tall, slender plants with long fibres.

Use of industrial hemp plant and its cultivation was commonplace until the 1900s, when it was associated with its genetic sibling akaDrug-Type Cannabis species (which contain higher levels of psychoactive THC). Influential groups misconstrued hemp as a dangerous ‘drug’, even though it is not a ‘drug’ and it has the potential to be a sustainable & profitable alternative crop.

The seeds are sown from mid-April to mid-May with grain drills to4–6 cm sowing depth. Hemp needs less fertilizer than corn does. A total of 60–150 kg of nitrogen, 40–140 kg phosphorus (P2O5) and75–200 kg of potassium per acre for hemp fibre made before sowing and again later, maybe three to four weeks. When practised, especially in France double use of fibre and seed fertilization with nitrogen doses up to 100 kg / ha rather low. Organic fertilizers such as manure can utilize industrial hemp well. Neither weeds nor crop protection measures are necessary.

Harvesting

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, and by moulds and bacterial action).

Location and crop rotation

For profitable hemp farming, particularly deep, humus-rich,nutrient-rich soil with controlled water flow is preferable. Waterlogged acidic, compressed or extremely light (sandy) soils primarily affect the early development of plants.[citation needed]Steep and high altitudes of more than 400 m above sea level are best avoided. Hemp is relatively insensitive to cold temperatures and can withstand frost down to −5 °C. Seeds can germinate down to 1–3°C. Hemp needs a lot of heat, so earlier varieties come to maturation. The water requirement is 300–500 l/kg dry matter. This is around 1/14th that of cotton, which takes between 7,000 and 29,000l/kg, according to WWF. Roots can grow up to 3 feet into the soil and use water from deeper soil layers.

Hemp benefits crops grown after it. So, it is generally grown before winter cereals. Advantageous changes are high weed suppression, soil loosening by the large hemp root system, and the positive effect on soil tilth. Since hemp is very self-compatible, it can also be grown several years in a row in the same fields(monoculture).

Diseases

Hemp plants can be vulnerable to various pathogens, including bacteria, fungi, nematodes, viruses and other miscellaneous pathogens. Such diseases often lead to reduced fibre quality, stunted growth, and death of the plant. These diseases rarely affect the yield of a hemp field, so hemp production is not traditionally dependent on the use of pesticides.

Environmental impact

Hemp is considered by a 1998 study in Environmental Economics to be environmentally friendly due to a decrease of land use and other environmental impacts, indicating a possible decrease of ecological footprint in a US context compared to typical benchmarks. A 2010study, however, that compared the production of paper specifically from hemp and eucalyptus concluded that “industrial hemp presents higher environmental impacts than eucalyptus paper”; however, the article also highlights that “there is scope for improving industrial hemp paper production”. Hemp is also claimed to require few pesticides and no herbicides, and it has been called a carbon negative raw material. Results indicate that high yield of hemp may require high total nutrient levels (field plus fertilizer nutrients) similar to a high yielding wheat crop.

Producers

The world-leading producer of hemp is China, which produces more than 70% of the world output. France ranks second with about a quarter of the world production. Smaller production occurs in the rest of Europe, Chile, and North Korea. Over 30 countries produce industrial hemp, including Australia, Austria, Canada, Chile, China,Denmark, Egypt, Finland, Great Britain, Germany, Greece, Hungary,India, Italy, Japan, Korea, Netherlands, New Zealand, Poland,Portugal, Romania, Russia, Slovenia, Spain, Sweden, Switzerland,Thailand, Turkey and Ukraine.

The United Kingdom and Germany resumed commercial production in the 1990s. British production is mostly used as bedding for horses; other uses are under development. Companies in Canada, the UK, theUnited States, 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.

Australia

In the Australian states of Tasmania, Victoria, Queensland, NewSouth Wales, and most recently, South Australia, the state governments have issued licences to grow hemp for industrial use. The first to initiate modern research into the potential of cannabis was the state of Tasmania, which pioneered the licensing of hemp during the early 1990s. The state of Victoria was an early adopter in 1998,and has reissued the regulation in 2008.

Queensland has allowed industrial production under licence since 2002, where the issuance is controlled under the Drugs Misuse Act1986. New South Wales now issues licences under a law, the HempIndustry Regulations Act 2008 (No 58), that came into effect as of 6 November 2008. Most recently, South Wales legalized industrial hemp under South Australia’s Industrial Hemp Act 2017, which commenced on 12 November 2017.

France

France is Europe’s biggest producer (and the world’s second largest producer) with 8,000 hectares cultivated.[83] 70-80% of the hemp fibre produced in 2003 was used for speciality pulp for cigarette papers and technical applications. About 15% was used in the automotive sector, and 5-6% was used for insulation mats. About 95% of hurds were used as animal bedding, while almost 5% was used in the building sector. In 2010/2011, a total of 11,000 hectares (27,000acres) was cultivated with hemp in the EU, a decline compared with previous year.

Russia and Ukraine

From the 1950s to the 1980s, the Soviet Union was the world’s largest producer of hemp (3,000 km2 in 1970). The main production areas were in Ukraine, the Kursk and Orel regions of Russia, and near the Polish border. Since its inception in 1931, the Hemp BreedingDepartment at the Institute of Bast Crops in Hlukhiv (Glukhov), Ukraine, has been one of the world’s largest centres for developing new hemp varieties, focusing on improving fibre quality, per-hectare yields, and low THC content.

After the collapse of the Soviet Union, the commercial cultivation of hemp declined sharply. However, at least an estimated 2.5 million acres of hemp grow wild in the Russian Far East and Black Sea regions.

United Kingdom

In the United Kingdom, cultivation licences are issued by the Home Office under the Misuse of Drugs Act 1971. When grown for non drug purposes, hemp is referred to as industrial hemp, and a common product is fibre for use in a wide variety of products, as well as the seed for nutritional aspects and for the oil. Feral hemp or ditch weed is usually a naturalized fibre or oilseed strain of Cannabis that has escaped from cultivation and is self-seeding.

United States

Hemp was made illegal to grow without a permit in the U.S. under the Controlled Substances Act passed in 1970 because of its relation to marijuana and any imported hemp products must meet a zero tolerance level. Some states have made the cultivation of industrial hemp legal, but farmers in many states have not yet begun to grow it because of resistance from the federal Drug EnforcementAdministration, making “large-scale hemp growing” in theUnited States “not viable” as late as 2013. In 2013, after the legalization of cannabis in the state, several farmers inColorado planted and harvested several acres of hemp, bringing in the first hemp crop in the United States in over half a century. Colorado, Vermont, California, and North Dakota have passed laws enabling hemp licensing. All four states are waiting for permission to grow hemp from the DEA. Currently, Oregon has licensed industrial hemp as of August 2009. Congress included a provision in the Agricultural Act of 2014 that allowed colleges and state agencies to grow and conduct research on hemp in states where it is legal. Hemp production in Kentucky, formerly the United States’ leading producer, resumed in 2014. Hemp production in North Carolina resumed in 2017, and in Washington State the same year. By the end of 2017, at least34 U.S. states had industrial hemp programs. In 2018, New York began taking strides in industrial hemp production, along with hemp research pilot programs at Cornell University, Binghamton University and SUNY Morrisville.

History

Hemp is possibly one of the earliest plants to be cultivated. An archaeological site in the Oki Islands near Japan contained cannabis achenes from about 8000 BC, probably signifying the use of the plant Hemp use archaeologically dates back to the Neolithic Age in China, with hemp fibre imprints found on Yangshao culture pottery dating from the5th millennium BC. The Chinese later used hemp to make clothes, shoes, ropes, and an early form of paper. The classical Greek historian Herodotus (ca. 480 BC) reported that the inhabitants of Scythia would often inhale the vapours of hemp-seed smoke, both as ritual and for their own pleasurable recreation.

Textile expert Elizabeth Wayland Barber summarizes the historical evidence that Cannabis sativa, “grew and was known in the Neolithic period all across the northern latitudes, from Europe(Germany, Switzerland, Austria, Romania, Ukraine) to East Asia (Tibet and China),” but, “textile use of Cannabis sativa does not surface for certain in the West until relatively late, namely theIron Age.” “I strongly suspect, however, that what catapulted hemp to sudden fame and fortune as a cultigen and caused it to spread rapidly westwards in the first millennium B.C. was the spread of the habit of pot-smoking from somewhere in south-central Asia, where the drug-bearing variety of the plant originally occurred. The linguistic evidence strongly supports this theory, both as to time and direction of spread and as to cause.”

Jews living in Palestine in the 2nd century were familiar with the cultivation of hemp, as witnessed by a reference to it in the Mishna(Kil’ayim 2:5) as a variety of plant, along with Arum, that sometimes takes as many as three years to grow from a seedling. In late medieval Germany and Italy, hemp was employed in cooked dishes, as filling in pies and tortes, or boiled in a soup. Hemp in later Europe was mainly cultivated for its fibres and was used for ropes on many ships, including those of Christopher Columbus. The use of hemp as a cloth was centred largely in the countryside, with higher quality textiles being available in the towns.