Hemp originated in Central Asia. Hemp cultivation for fibre was recorded in China as early as 2800 bce and was practiced in the Mediterranean countries of Europe early in the Christian era, spreading throughout the rest of Europe during the Middle Ages. It was planted in Chile in the 1500s and a century later in North America.
Hemp, (Cannabis sativa), also called industrial hemp, plant of the family Cannabaceae cultivated for its fibre (bast fibre) or its edible seeds. Hemp is sometimes confused with the cannabis plants that serve as sources of the drug marijuana and the drug preparation hashish. Although all three products—hemp, marijuana, and hashish—contain tetrahydrocannabinol (THC), a compound that produces psychoactive effects in humans, the variety of cannabis cultivated for hemp has only small amounts of THC relative to that grown for the production of marijuana or hashish.
Cultivation and processing
The hemp plant is a stout, aromatic, erect annual herb. The slender canelike stalks are hollow except at the tip and base. The leaves are compound with palmate shape, and the flowers are small and greenish yellow. Seed-producing flowers form elongate, spikelike clusters growing on the pistillate, or female, plants. Pollen-producing flowers form many-branched clusters on staminate, or male, plants.
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Hemp is grown in temperate zones as an annual cultivated from seed and can reach a height of up to 5 metres (16 feet). Crops grow best in sandy loam with good drainage and require average monthly rainfall of at least 65 mm (2.5 inches) throughout the growing season. Crops cultivated for fibre are densely sowed and produce plants averaging 2–3 metres (6–10 feet) tall with almost no branching. Plants grown for oilseed are planted farther apart and are shorter and many-branched. In fibre production, maximum yield and quality are obtained by harvesting soon after the plants reach maturity, indicated by the full blossoms and freely shedding pollen of the male plants. Although sometimes pulled up by hand, plants are more often cut off about 2.5 cm (1 inch) above the ground.
Conversely, European growing conditions for CBD resemble fiber conditions and the crop is often dual harvested for fiber and CBD. This CBD is produced at lower concentrations in the tops of fiber varieties. This method creates a dual-purpose production system and resembles densely-packed hemp fiber production as opposed to bushy, flowering marijuana.
In the regulatory realm, technically anything containing (even the minutest) concentrations of tetrahyrdocannabinol (THC) are regulated under the Drug Enforcement Agency’s Controlled Substance Act; however, the federal government allows states to create their own cannabis policies.
This confusion exists because marijuana was created by selectively breeding Indian hemp for Tetrahyrdocannabinol (THC). THC is the major differentiating factor between hemp and marijuana.
Growing for Phytocannabinoids
The major similarity when growing hemp and marijuana is when growing for the cannabinoids. In hemp’s case, farmers grow for the CBD and other minor cannabinoids, but legally require less than 0.3% of the cannabinoid THC. As for marijuana, unless growing for a particular ratio of THC : CBD, growers want the highest concentrations of THC and CBD possible. Because these production schemes both desire high concentrations of cannabinoids found in the floral material; the current growing conditions are similar.
Hemp and marijuana are both cannabis. But, hemp and marijuana are different varieties of the Cannabis sativa species.
For this reason, certain states have passed legislation for recreational and/or medical marijuana as well as the legal production of industrial hemp. The 2014 Farm Bill protects hemp production for research purposes and pilot scales within universities and State departments of agriculture. This is a federal bill.
Just like a marijuana grower, a hemp farmer growing for high concentrations of CBD would want to remove the male plants from the field or facility before pollination. This allows for less seed and higher concentrations of phytocannabinoids in each plant. Under this growing condition, hemp grown for phytocannabinoids like CBD commonly resembles marijuana production patterns.