Industrial hemp has many uses, including paper, textiles, biodegradable plastics, health food, and fuel. It is one of the fastest growing biomasses known, and one of the earliest domesticated plants known. It also runs parallel with the “Green Future” objectives that are becoming increasingly popular. Hemp requires little to no pesticides, no herbicides, controls erosion of the topsoil,and produces oxygen. Furthermore, hemp can be used to replace many potentially harmful products, such as tree paper (the processing of which uses bleaches and other toxic chemicals, and contributes to deforestation), cosmetics, and plastics, most of which are petroleum-based and do not decompose easily.
Licenses for hemp cultivation are issued in Europe and Canada. In the United Kingdom, these licenses are issued by the Home Office under the Misuse of Drugs Act of 1971. When grown for non-drug purposes hemp is referred to as industrial hemp, and a common product is fiber for use in a wide variety of products, as well as the seed for nutritional aspects as well as for the oil. Feral hemp or ditch weed is usually a naturalized fiber or oilseed strain of Cannabis that has escaped from cultivation and is 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. The major difference between the two types of plants is the appearance and the amount of Δ9-tetrahydrocannibinol (THC) secreted in a resinous mixture by epidermal hairs called glandular trichomes. Strains of Cannabis approved for industrial hemp production produce only minute amounts of this psychoactive drug, not enough for any physical or psychological effects. Typically, Hemp contains below 0.3% THC, while Cannabis grown for marijuana can contain anywhere from 6 or 7 % to 20% or even more.
Industrial Hemp is produced in many countries around the world. Major producers include Canada, France, and China. The United States is the only industrialized nation to continue to ban industrial hemp. While the Hemp is imported to the United States more than to any other country, theUnited States Government does not distinguish between marijuana and non-psychoactive Cannabis used for industrial and commercial purposes.
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
*Hemp has been grown for at least the last 12,000 years for fiber (textiles and paper) and food. It has been effectively prohibited in the United States since the 1950s.
*George Washington and Thomas Jefferson both grew hemp. Ben Franklin owned a mill that made hemp paper. Jefferson drafted the Declaration of Independence on hemp paper.
*When US sources of “Manila hemp” (not true hemp) was cut off by the Japanese in WWII, the US Army and US Department of Agriculture promoted the “Hemp for Victory” campaign to grow hemp in the US.
*Because of its importance for sails (the word “canvass” is rooted in “cannabis”) and rope for ships, hemp was a required crop in the American colonies.
*Henry Ford experimented with hemp to build car bodies. He wanted to build and fuel cars from farm products.
*BMW is experimenting with hemp materials in automobiles as part of an effort to make cars more recyclable.
*Much of the bird seed sold in the US has hemp seed (it’s sterilized before importation), the hulls of which contain about 25% protein.
*Hemp oil once greased machines. Most paints, resins, shellacs, and varnishes used to be made out of linseed (from flax) and hemp oils.
*Rudolph Diesel designed his engine to run on hemp oil.
*Kimberly Clark (on the Fortune 500) has a mill in France which produces hemp paper preferred for bibles because it lasts a very long time and doesn’t yellow.
*Construction products such as medium density fiber board, oriented strand board, and even beams, studs and posts could be made out of hemp. Because of hemp’s long fibers, the products will be stronger and/or lighter than those made from wood.
*The products that can be made from hemp number over 25,000.
*Industrial hemp and marijuana are both classified by taxonomists as Cannabis sativa, a species with hundreds of varieties. C. sativa is a member of the mulberry family. Industrial hemp is bred to maximize fiber, seed and/or oil, while marijuana varieties seek to maximize THC (delta 9 tetrahydrocannabinol, the primary psychoactive ingredient in marijuana).
*While industrial hemp and marijuana may look somewhat alike to an untrained eye, an easily trained eye can easily distinguish the difference.
*Industrial hemp has a THC content of between 0.05 and 1%. Marijuana has a THC content of 3% to 20%. To receive a standard psychoactive dose would require a person to power-smoke 10-12 hemp cigarettes over an extremely short period of time. The large volume and high temperature of vapor, gas and smoke would be almost impossible for a person to withstand.
*If hemp does pollinate any nearby marijuana, genetically, the result will always be lower-THC marijuana, not higher-THC hemp. If hemp is grown outdoors, marijuana will not be grown close by to avoid producing lower-grade marijuana.
*Hemp fibers are longer, stronger, more absorbent and more mildew-resistant than cotton.
*Fabrics made of at least one-half hemp block the sun’s UV rays more effectively than other fabrics.
*Many of the varieties of hemp that were grown in North America have been lost. Seed banks weren’t maintained. New genetic breeding will be necessary using both foreign and domestic “ditchweed,” strains of hemp that went feral after cultivation ended. Various state national guard units often spend their weekends trying to eradicate this hemp, in the mistaken belief they are helping stop drug use.
*A 1938 Popular Mechanics described hemp as a “New Billion Dollar Crop.” That’s back when a billion was real money.
*Hemp can be made in to a variety of fabrics, including linen quality.
*The US Drug Enforcement Agency classifies all C. sativa varieties as “marijuana.” While it is theoretically possible to get permission from the government to grow hemp, DEA would require that the field be secured by fence, razor wire, dogs, guards, and lights, making it cost-prohibitive.
*The US State Department must certify each year that a foreign nation is cooperating in the war on drugs. The European Union subsidizes its farmers to grow industrial hemp. Those nations are not on this list, because the State Department can tell the difference between hemp and marijuana.
*Hemp was grown commercially (with increasing governmental interference) in the United States until the 1950s. It was doomed by the Marijuana Tax Act of 1937, which placed an extremely high tax on marijuana and made it effectively impossible to grow industrial hemp. While Congress expressly expected the continued production of industrial hemp, the Federal Bureau of Narcotics lumped industrial hemp with marijuana, as it’s successor the US Drug Enforcement Administration, does to this day.
*Over 30 industrialized democracies do distinguish hemp from marijuana. International treaties regarding marijuana make an exception for industrial hemp.
*Canada now again allows the growing of hemp.
* Hemp growers can not hide marijuana plants in their fields. Marijuana is grown widely spaced to maximize leaves. Hemp is grown in tightly-spaced rows to maximize stalk and is usually harvested before it goes to seed.
*Hemp can be made into fine quality paper. The long fibers in hemp allow such paper to be recycled several times more than wood-based paper.
*Because of its low lignin content, hemp can be pulped using less chemicals than with wood. Its natural brightness can obviate the need to use chlorine bleach, which means no extremely toxic dioxin being dumped into streams. A kinder and gentler chemistry using hydrogen peroxide rather than chlorine dixoide is possible with hemp fibers.
*Hemp grows well in a variety of climates and soil types. It is naturally resistant to most pests, precluding the need for pesticides. It grows tightly spaced, out-competing any weeds, so herbicides are not necessary. It also leaves a weed-free field for a following crop.
*Hemp can displace cotton which is usually grown with massive amounts of chemicals harmful to people and the environment. 50% of all the world’s pesticides are sprayed on cotton.
*Hemp can displace wood fiber and save forests for watershed, wildlife habitat, recreation and oxygen production, carbon sequestration (reduces global warming), and other values.
*Hemp can yield 3-8 dry tons of fiber per acre. This is four times what an average forest can yield.
*If one tried to ingest enough industrial hemp to get ‘a buzz’, it would be the equivalent of taking 2-3 doses of a high-fiber laxative.
*At a volume level of 81%, hemp oil is the richest known source of polyunsaturated essential fatty acids (the “good” fats). It’s quite high in some essential amino acids, including gamma linoleic acid (GLA), a very rare nutrient also found in mother’s milk.
*While the original “gruel” was made of hemp seed meal, hemp oil and seed can be made into tasty and nutritional products.
Prepared by the North American Industrial Hemp Council, October 1997
If you would like more information about hemp use and research, please visit the links below:
Cannabis Sativa Industrial hemp has many uses, including paper, textiles, biodegradable plastics, health food, and fuel. It is one of the fastest growing biomasses known, and one of the earliest
Extension Richland County
University of Wisconsin-Madison
Feral Hemp, aka “Ditch Weed”
Feral Hemp aka “Ditch Weed”
There are no publicly available seed collections of hemp (Cannabis Sativa) in the United States after previous collections were destroyed when the government never expected hemp would return as a crop. However, this prohibition has now effectively ended.
The Hemp Farming Act, part of the 2018 Farm Bill, removed hemp, previously labeled a Schedule 1 narcotic, from the Controlled Substances Act of 1970. Now that hemp is once again federally legal to grow there is a great need develop a new seed bank so researchers and breeders can produce high quality and high yielding cultivars that are regionally adaptive.
Despite active efforts to kill feral hemp populations throughout the Midwest, there are still large standing populations. Collecting seeds from these populations will be key to the success of the hemp industry in the United States.
If you are aware of any feral hemp populations, please contact Dr. Shelby Ellison of the University of Wisconsin-Madison. Dr. Ellison will send along collection instructions or make arrangements
to collect seeds.
Feral Hemp, aka Ditch Weed, is being sought for collection of its' seeds. Dr. Shelby Ellison is asking for help in collection of the seeds.