It's fairly common for people who are unacquainted with cannabis to wonder: Is hemp weed? Although hemp and marijuana are both classified biologically as cannabis, there are a number of important differences between them. These differences are evident in the way each variety is used.
The differences are also documented in the language, laws, and regulations that apply to both. We break down the anatomy, history, use, and legality of the hemp plant to get to the heart of not only what distinguishes it from marijuana, but also what makes it such a viable, versatile commodity.
What is hemp?
A variety of Cannabis sativa L, hemp is a dioecious plant, which means it can be separated into male and female plants. These plants have served a wide variety of purposes for more than 10,000 years: for fiber (from the plant's stems), protein (from seeds), and oils and smokable portions (from the leaves and flowers). Hemp fibers can be used to make items including paper, clothing, furnishing fabric, rope, and building materials.
The whole hemp plant, from stalk to seed, can also be used to make fuel and feedstock. For more specific applications, hemp can be divided into four categories:
- Bast fibers
- Hurds, or shives
- Leaves and flowers
Does hemp have THC?
The hemp plant produces a broad range of cannabinoids, including tetrahydrocannabinol (THC), the intoxicating cannabinoid in marijuana. However, hemp does not produce enough THC to create intoxicating effects when consumed.
Although the hemp plant doesn't produce a significant amount of THC, it is capable of producing the non-intoxicating and medicinally rich cannabidiol (CBD) in high concentrations. In fact, hemp-derived CBD is rapidly becoming one of the most popular forms of the therapeutic cannabinoid on the market today.
Many countries differentiate hemp vs. marijuana by the amount of THC produced per weight of a dry plant. In the U.S., industrial hemp is defined as a Cannabis sativa L. plant not containing more than 0.3% THC. The European Union has set the limit at 0.2%, while in Great Britain the limit is zero, unless growers have a cultivation license to grow industrial hemp with no more than 0.2% THC.
Can you smoke hemp?
Hemp isn't completely absent of intoxicating compounds, but that doesn't mean it will get you high. Hemp plants simply don't produce enough THC to have an intoxicating effect. CBD, though psychoactive, is a non-intoxicating cannabinoid and won't produce any form of a euphoric high on its own.
Technically speaking, you can smoke hemp if really want to but it won't get you high. In fact, smoking is not the best way to tap into the therapeutic potential of the cannabinoids that hemp is rich in, most notably CBD. For that, you'll be better served by consuming a hemp-derived CBD product such as CBD oil or tincture.
How are hemp varieties chosen?
Depending on the desired final product, hemp cultivars are chosen based on several factors, including:
- Stem quality
- Cannabinoid content
- Resistance to disease
- Time to harvest
- Hemp oil content
- Seed production per acre
CBD production, in particular, has become a major factor in recent years. As the CBD market continues to grow, more and more cultivars are also being chosen based on their CBD production and unique aromatic, or terpene, profiles.
What is hemp used for?
CBD oil is extracted from hemp leaves and flowers. The CBD oil extracted from hemp can be used for treating a wide variety of ailments, hence the ever-growing popularity of CBD-focused cultivation.
Hemp fibers are primarily used for textiles, paper, building materials, and other industrial products. Raw materials such as hurds, or shives, are short woody fibers typically found inside the stalk. They're used for making bedding materials, absorbents, particle board, ceiling panels, compost, and other industrial products.
Bast fibers make up the outer portion of the stalk and are typically split into three categories — primary, or line fiber, secondary, and tow. They are categorized according to their cell strength and cell wall thickness, which will determine the fiber's strength, durability, and ultimately what it can be used for.
How is hemp used as a food product?
Hemp seeds are rich in protein, dietary fiber, vitamins, and minerals. They contain an optimal ratio of omega-6 to omega-3 fatty acids for healthful consumption. A 2008 study also found that hemp proteins are more digestible for humans than common soy protein isolates (SPIs) used in food products.
Hemp can be used as a food product as either raw seeds or oils. Hemp oil is pressed from the seeds for a concentration of protein, meaning both food product forms are utilizing hempseed as a nutritional resource. Seeds can also be ground up for flour or mixed with water to create hempseed milk.
What are hemp fibers and leaves used for?
CBD oil is extracted from hemp leaves and flowers. The CBD oil extracted from hemp can be used for treating a wide variety of ailments, hence the ever-growing popularity of CBD-focused hemp cultivation.
Hemp fibers are primarily used for textiles, paper, building materials, and other industrial products. Hurds, or shives, are short woody hemp fibers typically found inside the stalk. They're used for making hempcrete, bedding materials, absorbents, particle board, ceiling panels, compost, and other industrial products. Bast fibers make up the outer portion of the stalk and are typically split into three categories — primary, or line fiber, secondary, and the tow. They are categorized according to their cell strength and cell wall thickness, which will determine the fiber's strength, durability, and ultimately what it can be used for.
How is hemp processed?
Many types of processing techniques are utilized to process hemp seeds and stalks. The technique used depends on the purpose of the final product.
Seeds can be consumed whole, or refined by being pressed or crushed to produce hemp seed oil and flour. These seeds are also hulled, or shelled, to make them more palatable. The remaining shells, which are rich in fiber, can also be used for making flour.
Hemp stalks are processed through decorticating, a multistep method for removing the long fibers from the rest of the plant. The steps taken during the intermediate processing period include:
Hemp stalks have tough cellular tissue that makes up their surface and must be dissolved through a process called retting. There are three modes of retting:
- Field retting: The plants are cut and laid on the field for four to six weeks, turned periodically. During this time, any bacteria on the plant's surface will break down the outer layer of the stalk. The retted stalks are then dried.
- Water retting: The stalks are immediately dried after harvesting, then placed into water for a few days. The water is used to soften the outer layer of the stalks and to help promote the growth of additional bacteria which helps accelerate the process.
- Chemical retting: Acids, bases, and special enzymes are used to break down the compounds that hold together the strong bast fibers.
All retted stalks should be dried until they have less than 15% moisture. Anything above 15% can potentially harbor and promote the growth of fungi and bacteria. If the stalks get too dry, meaning less than 10% moisture, they can become too brittle to transport.
The decorticating process typically involves three stages:
- Scutching: The stalks are passed through a series of rollers to break apart the hemp fibers. During this step, the woody core is pushed out and separated from the pliable fibers. This is another step where proper drying comes into play. The sweet spot is between 10% and 15% moisture and is key here. If the stalks are too dry, they will be crushed into a powder. If they are too moist, they won't break and separate properly.
- Hackling: The short and intermediate fibers are combed out of the stalk.
- Twisting: The fibers are individually twisted into yarn.
Modern decorticating techniques employ steam explosion (treating the fibers with steam through a pressurized chamber) and ultrasonic breaking (breaking down fibers using ultrasonic waves) to maintain the integrity of the fibers throughout the process. These techniques are not as harsh on the stalks and allow processors to use the fibers on already fabricated cotton and wool processing machinery.
3. Baling and storing
Hemp stalk is baled for transportation and long-term storage using traditional farming balers. Large, round balers are best because they allow for more thorough drying as they don't pack the hemp as tightly as square balers. Hemp bales should be stored in a dry environment in conditions intended to reduce as much humidity as possible. It's also important to check for wet patches during baling to further avoid mold.
How is hemp cultivated differently than marijuana?
Other key differences between hemp and marijuana have to do with cultivation and harvesting. Male plants flower much faster than females and do not produce nearly as much fiber. In stark contrast to marijuana fields, most female hemp fields include sporadically placed males. The male hemp plants release pollen for the female plant to produce seeds that will either be used for future crops or sold as food.
In marijuana fields, male plants are typically eliminated to ensure the maximum production of sinsemilla flowers.
While marijuana cultivation requires ample spacing to reduce the risk of mold or bacteria, hemp can be planted more densely. Most marijuana crops are planted at one plant per four square feet. Hemp plants that are grown for oil are planted at roughly 40 to 60 plants per four square feet. Those grown for fiber are even more densely planted at a rate of about 100 to 120 plants per four square feet.
Hemp plants are almost always cultivated outdoors, as opposed to marijuana plants, which are often planted in greenhouse or indoor settings. Because hemp is susceptible to the same predators, diseases, and insects that attack marijuana, many cultivators employ a technique called crop rotation, in which alternating crops are planted in the same place, to avoid any buildup of these organisms and to allow nutrients to return to the soil.
The specific order of crop rotation and types of crops being rotated with hemp will depend on the location of the farm. Hemp is also used as a rotational crop at farms where it is not the primary agricultural product.
Is hemp cultivation legal in the U.S.?
The 2014 Agricultural Act, more commonly known as the 2014 Farm Bill, signed by Democratic President Barack Obama, includes section 7606, which allows for universities and state departments of agriculture to cultivate industrial hemp, as long as it is cultivated and used for research. Under the 2014 Agricultural act, state departments and universities must also be registered with their state, and defer to state laws and regulations for approval to grow hemp.
As part of the Agriculture Improvement Act of 2018, or the 2018 Farm Bill, signed by Republican President Donald Trump, the Hemp Farming Act of 2018 reclassified hemp (with less than 0.3% THC) from Schedule I, the most restrictive classification of controlled substances by the federal government, and are considered highly prone to abuse and to not have any medicinal benefits. This move to federally legalize industrial production of the plant allowed for cultivation and distribution as a legal agricultural product.
Under the Hemp Farming Act, hemp cultivation is no longer limited to state departments and universities. In addition, the act allows farmers rights to water, crop insurance, and federal agricultural grants, as well as legal access to national banking. Hemp may also be transported across state lines.
Prior to the Hemp Farming Act of 2018, 41 states had passed industrial hemp-related legislation. Thirty-nine of those states legalized statewide cultivation programs that defined hemp specifically to differentiate it from marijuana, establish licensing requirements, and regulate production.
The Hemp Farming Act now requires state departments of agriculture to consult with their governors and chief law enforcement officers on a regulatory program, which will then be submitted to the United States Secretary of Agriculture for approval. According to Section 297B of the bill, state hemp regulatory programs must include a system to maintain information on all land where cultivation takes place, procedures for testing THC levels in hemp, and procedures for disposing of products that violate THC content restrictions.
World history of hemp
Hemp has been cultivated on a global scale for thousands of years. The oldest documented evidence of hemp cultivation is a rope, which dates back to 26,900 BCE, found in today's Czech Republic.
Some of the earliest known prolific uses of hemp began in China about 10,000 BCE, where it was used for making clothing, rope, and paper. The Yangshao people, who lived in China from roughly 5000 BCE, wove hemp and pressed it into their pottery for decorative purposes. From about 5000 to 300 BCE, the plant was also grown in Japan and used for fiber and paper.
Cannabis played a large role in the Greco-Roman cultures as a source of fiber, intoxication, and medicine. Cannabis seeds were discovered in the ruins of Pompeii, and Greek rhetorician Athenaeus made note of hemp being used to make rope between 170 and 230 CE. Roman author and naturalist Pliny the Elder also made reference to a cannabis root decoction as a treatment for joint stiffness and gout in the first century BCE.
Exactly how and when hemp originated in the New World is still highly debated. Though long thought to be introduced to the Americas by Christopher Columbus, hemp has been discovered in Native American civilizations that predate Columbus' arrival. William Henry Holmes' “Prehistoric Textile Art of Eastern United States” report from 1896 notes hemp from Native American tribes of the Great Lakes and Mississippi Valley.
Hemp products from pre-Columbian native civilizations were also found in Virginia. Vikings, who used the plant for making rope and sails, may also have brought seeds with them when they attempted to colonize the New World.
Jamestown settlers introduced hemp to colonial America in the early 1600s for rope, paper, and other fiber-based products; they even imposed fines on those who didn't produce the crop themselves. U.S. presidents George Washington and Thomas Jefferson grew hemp.
Hemp was a prominent crop in the United States until 1937, when the Marihuana Tax Act virtually obliterated the American hemp industry. During World War II, the crop saw a resurgence in the U.S., as it was used extensively to make military items including uniforms, canvas, and rope. The U.S. Department of Agriculture (USDA) even released a short documentary, “Hemp for Victory,” in 1942, which promoted the plant as a useful crop for the war cause.
The World War II hemp resurgence was short-lived, though. Until the passing of the 2014 Farm Bill, the Controlled Substances Act of 1970 kept industrial production dormant. Today, hemp is rapidly becoming an indispensable resource for CBD oil and other CBD products.
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