Over the centuries, people have cultivated hemp plants for their edible seeds and fiber. The hemp plant is high yield, versatile, and has a range of uses. We use it for textiles, medicine, food products, cosmetics, building, and so much more. Meanwhile, a quick browse for sustainable products and hemp is bound to crop up. So what is hemp, is it a sustainable material, and how is it used today?
Hemp is a species of cannabis plants. We know its scientific name to be Cannabis Sativa L. We also refer to it as industrial hemp.
Industrial hemp is not the same as marijuana plants, although they both belong to the family of cannabis Sativa plants. There are different varieties of cannabis cultivated for three primary purposes. Growers produce the first group of cannabis for recreational purposes; these include marijuana and hashish. They grow the second group for seeds, from which we extract oil, and the third group is mainly for fiber. We categorize the second and third groups as industrial hemp2.
An acre of hemp produces as much fiber as 2-3 acres of cotton per year. The hemp plant is tolerant of frosty climates and has a strong resistance to pests and weed encroachment. Hemp grows well with moderate amounts of water and fertilizer. An acre of hemp can produce the same amount of paper that we get from about 4 acres of trees. As such, hemp has many qualities that make it valuable as a more preferred sustainable resource.
Perhaps the best thing about hemp is that it is an organic material. It propagates rapidly, and every part of the plant is useful.
The cannabis plant species known as hemp has low tetrahydrocannabinol (THC) content and is not useful for recreational purposes. Whereas THC is present in all hemp varieties, industrial hemp contains only small levels.
Another natural compound found in hemp is cannabidiol; CBD is present in all Cannabis Sativa plants, including hemp and marijuana. A wide variety of treatments people use for mental disorders, insomnia, and glaucoma contain THC and CBD. THC and CBD have similar molecular structure but have a fundamental difference in their effects on the human body.
CBD binds weakly to the body’s CB1 receptors, but THC has no such difficulty. It binds strongly and causes a person to experience a feeling of euphoria. On the other hand, CBD does not give a person the feeling of being “high.” Because of their low binding strength, CBD products have THC to help bind to the cb1 receptors. Hemp products used for their THC contents need CBD to help reduce the unwanted psychoactive effects.
The psychoactive effects of THC make it a controlled substance; therefore, legal hemp must contain 0.3 THC or less on a dry weight basis. In the United States, hemp is no longer under the controlled substances act. Washington DC and 33 other states enforced cannabis-related laws and made medical cannabis with high levels of THC legal.
The distinction between industrial hemp and other varieties of the cannabis family is that hemp contains negligible THC amounts. Thus industrial hemp does not give the high effect of marijuana and other varieties of cannabis. Marijuana can contain up to 30% THC on a dry weight basis. In the variety grown for recreation, they remove the male plants to prevent fertilization.
Hemp might be one of the first cultivated plant fibers. Agriculture started about 10,000 years ago, and research has traced hemp back to 8000 BC. We believe it to be one of the oldest proofs of human industry. Archaeologists discovered a piece of clothing made with hemp that dates back to 8,000 BC in Mesopotamia. Mesopotamia is an area in modern-day Iraq and Taiwan. They also found pottery shards imprinted with hemp in China.
There are references to an emperor of China; Emperor Shen Nung teaching his subjects to cultivate hemp for cloth. China seems to have the longest history of hemp cultivation. They began using hemp to make paper around 150 BC. Other historical uses of hemp include pottery, food, and medicine.
The hemp plant is also culturally significant to some ancient civilizations. The Hindus and Persians’ ancient religious documents refer to it as a “sacred grass” or “king of seeds.”
Hemp arrived in Europe around 1200 BC, and from there, it spread quickly to other parts of the world.
Immigrants introduced hemp to North America in 1606. Farmers were legally bound to engage in hemp cultivation in the 1700s. Hemp was a prominent American crop from 1776 to 1937. Even George Washington, a former President of the United States, had a hemp farm on his estate.
In 1916, the United States Department of Agriculture published findings that proved hemp was a more sustainable paper source. Some years later, the government placed the marijuana tax act on the sale of all cannabis products, strongly discouraging hemp cultivation.
An experimental car produced by henry ford in 1942 used hemp fiber instead of steel for the car’s body. The body proved to be ten times stronger than steel. In the same year, the United States Department of Agriculture launched a “hemp for victory” program. This encouraged the production of about 150,000 acres of hemp.
The soviet union was the world’s largest hemp producer from the 1950s to the 1980s. Their major production sites were in Ukraine, the Orel regions of Russia, and near the Polish border. China, Romania, Italy, Poland, France were also producing hemp around that time. The United Kingdom, Germany, and Canada resumed commercial hemp production in the 1990s.
In the United States, the controlled substances act of 1970 classified hemp and marijuana illegal. The federal government imposed strict regulations on the cultivation of marijuana and industrial hemp. The hemp industry suffered greatly as a result of this long-term prohibition of hemp and marijuana.
Prohibition remained in place until President Donald Trump signed the 2018 farm bill into law. The farm bill made hemp and all of its derivatives legal. The 2018 farm bill was a success after several previous attempts to legalize hemp.
Prior, in 2014, President Barack Obama had signed the farm bill that allowed limited hemp farming. At this time, policy permitted only state departments of agriculture and educational research institutions to pilot industrial hemp farming.
The Canadian government also banned the cultivation of cannabis. However, research conducted between 1994 to 1998 showed that farmers could grow industrial hemp as a separate breed from marijuana. This influenced the decision made by Health Canada to give controlled hemp farming a chance. Canada issued the first industrial hemp farming license in May 1998. Since then, the number of permits has grown.
Presently, companies in Canada, the United Kingdom, Germany, and the United States use hemp seed in food and cosmetics products.
Throughout history, we have successfully used hemp for a variety of purposes. We use the leaves, stalks, and seeds to produce clothing, medicine, fuel, and clothing . Thanks to how quickly the plant grows, it is capable of supplying resources continuously.
Hemp fiber is mildew resistant and is highly durable. It is long, usually measuring over 1.8 meters with individual cylindrical cells with an irregular surface. Hemp fibers last twice as long as cotton fibers, and they are longer and less flexible than flax. Their coloring is usually yellowish, greenish, greyish, or dark brown. They rarely dye it.
The Italian hemp industry processes some fibers with a whitish color and luster to make them similar to linen. Hemp fiber is durable and unaffected by water. The fabric made from hemp fiber is suitable for people with sensitive skin as it does not cause allergies. Fabric producers often combine hemp fiber with other fibers like flax, silk, cotton, and polyester.
As a result, manufacturers use hemp fibers to make hemp clothing and furnishings. Many familiar with hemp’s use as a fabric praise its softness and long-lasting qualities. Further, as it's naturally breathable and durable, it makes an excellent raw material for socks through t-shirts. Hemp backpacks with their distinctive Himalayan styles have also become popular for those seeking an earth-friendly look and practicality. Often made in Nepal, these carry-alls are better for the environment than cotton or nylon, and they last longer too.
Other uses for the fiber includes mulch, litter, and animal bedding. Hemp fibers have good tensile strength and are also useful for strong ropes, twine, cable, strings, and other cords. Other manufacturers across sectors also use the fiber to make ship sails, burlap sacks, artificial sponges, and canvas. They also make sturdy and comfortable shoes from hemp fiber.
The adaptation of hemp in textiles may help to reduce the unfavorable environmental impact of cotton and plastic-based fibers.
Paper manufacturers also use hemp to produce all types of paper, from tissue to cardboard. Its content is 70% cellulose. Proponents suggest hemp paper proves superior compared to tree-based paper. Paper made from hemp can last 100 years without degrading. The manufacturing process of hemp paper requires less toxic chemicals than tree paper. Further, we can recycle it a lot more times than we can recycle paper made from trees.
These qualities make hemp perfect for everything from writing paper to hemp drinking straws.
About 70% of the cannabis plant’s total weight is the hurd or inner woody core. The hurd has no THC content and has found uses in housing construction. When they combine the unslaked lime with the silica present in the hurd, it creates a chemical bond similar to cement. The bond formed is both fire and waterproof. The hurd provides excellent insulation. Hurd is cheaper than wood and more sustainable than other building materials that perform similar functions.
“Hempcrete” is a concrete formula made of hemp. It is seven times stronger, three times more pliable, and weighs only half as much as traditional concrete. Hempcrete is an excellent option for the construction of walls and foundations.
Hemp seeds are non-intoxicating, and historically they are used as bird feed. The shelled seeds are called hemp hearts, and you can eat them directly as health food. They are a valuable food product that contains protein. Two tablespoons of hemp hearts contain two grams of fiber, five grams of protein, and 300mg of potassium. You’ll also benefit from receiving 15% of your vitamin A requirement and 25% of your daily iron needs.
The protein in hemp seeds is more nutritious and costs less to produce when compared to soybean protein. Therefore, food manufacturers have begun using Hemp seed protein in products using milk, cheese, tofu, butter, salad oils, ice cream, etc.
You’ll also find hemp seeds ground into a nutritious flour. We can use hemp seed flour to bake cookies, bread, and pasta.
For a long time, those who keep birds have used hemp seeds for feed. Birds that feed on hemp seeds live longer and produce more offspring. Further, farmers have begun to feed livestock with a cake made from hemp seeds, a meal made from pressing them together. This cake is highly nutritious and satisfies the dietary needs of most animals.
Pressed hemp seeds release oil. As a result, industry can use hemp seed oil to produce non-toxic diesel fuel. They can also use hemp to make paint, detergent, ink, varnish, and lubricating oil. We also use the oil extracted from hemp for cooking and in plastic products.
Hemp oil contains nutrients researchers have shown as beneficial to the skin and hair. It is a special ingredient in some zero waste makeup products, skincare products, and hair care creams. Hemp seeds are a viable source of these products because they account for half the mature plant’s weight.
We can derive two fuel types from hemp; biodiesel from the seeds and biofuel from the hemp stalks. We source the biodiesel from hemp seed oil, while the biofuel comes from hemp stalks. Just like corn, we can convert hemp to ethanol fuel. And it is even more viable than corn as a source of ethanol fuel because of its abundance of biomass. Biodiesel obtained from hemp works well with conventional diesel engines.
The fuel from hemp is environmentally friendly and more affordable than fossil fuels. The fuel is biodegradable and pollutes less than fossil fuel-based sources. The process of producing hemp fuel is non-toxic and has a less negative effect on the environment. We can grow hemp almost anywhere, unlike fossil fuel, which we can only source from specific locations. This means it will be easier to access hemp fuel. If hemp fuel becomes as popular as fossil fuel, we can grow our own renewable, endless fuel supply.
Hemp has an abundance of cellulose from which we can make biodegradable plastics. If properly harnessed, hemp has the potential to be a replacement for plastic. This is great for the environment because plastic products made from nonrenewable resources pollute the environment. Plastic made from hemp cellulose is stronger and better for the environment than those made from petrochemicals. Although, like other plastics, it still poses serious concerns.
The use of hemp for medicine is controversial due to the psychoactive effects of tetrahydrocannabinol. But more and more people are finding CBD products effective in promoting their physical and mental wellbeing. Epidiolex is a prescription drug used to treat rare forms of epilepsy that contains CBD. Medication containing CBD can treat inflammation, anxiety, pain, psychosis, nausea, and inflammatory bowel disease.
Hemp is a stout, strong-smelling, straight-standing herb with slender hollow stalks except at the tip and base. Its leaves are palmate shaped, and it sprouts small greenish-yellow flowers.
Hemp plants grow faster than trees; they are ready for harvest in about 60 to 120 days. Further, hemp farming requires less space than tree farming for equivalent yields.
Hemp crops grow well on most soils suitable for farming. To ensure successful hemp cultivation, the soil should be free of weeds. It should also be in a fine mellow state of mould. Soil fertilization is essential in ensuring a bountiful harvest of hemp. Well-rotted manure will suffice perfectly for that purpose.
It is essential to plant only new seeds that are of excellent quality. You can determine if a seed is of good quality by its weight and color to a limited extent. A good seed feels heavy and has a shiny bright color. It is important to ensure that you do not sow the hemp plants too close together, as this can cause low growth or crop injuries. At their early stage, hemp plants are very tender. It is important to protect the plants from frost and pests like birds. The hemp plant can favorably compete with weeds as it grows.
Hemp produces more biomass than any plant species grown in a wide range of locations and climatic conditions. However, the location of the farm can affect yield and quality1.
Harvest time for hemp cultivated exclusively for fiber is before the plant flowers. This is because the fiber quality may reduce once it flowers. Harvesting hemp does not cause erosion as opposed to logging, which causes water pollution and loss of topsoil. Farmers harvest hemp by hand or with mechanical harvesters. They cut the plants at about 2cm above the soil. Once cut, farmers leave the harvested hemp on the ground to dry for about four days.
After this comes the retting. Traditionally there are two types of retting; we have dew retting and wet retting. In wet retting, bundles of hemp float in water. Growers lay the hemp on the floor in dew retting, where dew, molds, and bacteria action affects it. We know the modern process as thermo-mechanical pulping. It is the use of steam and machinery to separate the fiber.
After completing the retting process, drying, crushing, and shaking follow to complete the fiber extraction process.
Selective breeding has produced hemp varieties with distinct physical differences. To mitigate hemp’s sometimes controversial use for medicine and recreation, breeders have directed their efforts towards creating varieties that have negligible amounts of tetrahydrocannabinol.
The US is one of the few countries in the lead of adopting hemp use. The 2018 farm bill passed in America was a win for hemp farmers. It is also an important step towards a more sustainable natural resource management.
The HIA continues to educate the public about the benefits of hemp. The association aims to dispel the misconceptions surrounding the hemp plant. With public acceptance and industrial maximization, hemp could once again become America’s top cash crop. Although the USA has made hemp legal, the USDA wants to retain control over many aspects of the industry. So it may take a while for large-scale hemp farming to spread across the country.
In Canada, the law permits farmers to grow industrial hemp under controlled circumstances. A person who wants to go into hemp farming in Canada would need special licenses, permits, and authorization.
Scientists may discover even more uses for hemp, making it even more profitable than it already is.
Cannabis Sativa L, otherwise known as hemp cannabis, is a plant that proves itself useful in more than one way. They make a wide variety of products we use in our everyday life, from its oil, seed, fibers, and other extracts. The plant has the potential to push sustainable consumerism forward and revolutionize the world’s economy. Cultivating hemp can also make our industrial processes more eco-friendly.
|Industrial Hemp Harvest and Storage, Best Management Practices, Alberta Agriculture and Rural Development|
|Roseberg, R & Summers, S & Jones, Gordon & Sikora, Vladimir & Noller, Jay & Rondon, Silvia & Jeliazkov (Zheljazkov), Valtcho & Angima, Sam. (2019). What is Industrial Hemp?.|