Hemp, a species of cannabis plant, has been valued since ancient times for its fibers and seeds, but it’s been illegal to grow in the U.S. for decades. That all changed in late 2018 with the passage of the 2018 Farm Bill. It included a section legalizing hemp production, paving the way for what many are calling the next big cash crop.
Hemp has many uses, ranging from food to fiber, but it’s also the source of the hemp-derived compound cannabidiol (CBD), which shows promising medical uses. The CBD market in the U.S. was estimated at $600 million in 2018, with projections shooting up over $20 billion by 2022.1
The change in hemp’s legal status was a long time coming and paves the way for this beneficial plant to be treated like other crops, instead of an illegal substance.
The History of Hemp
The legalization of hemp is cause for celebration for more than just hemp supporters, who have been spearheading legalization attempts for decades. The move has ramifications for human health and the environment, now that this plant will no longer be treated as an illicit drug.
Hemp has been valued for thousands of years, with perhaps the oldest discovery of hemp dating back to a piece of hemp fabric from 8,000 B.C.2 As noted by the National Hemp Association, hemp has been used throughout the world for centuries:3
“The spread of cannabis took place from China to the Middle East and the Mediterranean area and, subsequently, to Europe, probably via nomadic peoples. Starting around the year 600, the Germans, Frankish tribes and Vikings produced rope, cloth and garments from hemp fiber.
In the Middle Ages, most people wore hemp sandals. Many farmers grew hemp on a small scale. Since the Middle Ages, the industrial use of hemp has seen a number of peaks.”
In the 17th century, for instance, ships took to the seas with sails and lines made from braided hemp fibers. Hemp clothing was also popular, and Rembrandt used hemp paper for sketching. In the U.S., Presidents Washington and Jefferson grew hemp, and according to the Hemp Industries Association (HIA), “Americans were legally bound to grow hemp during the Colonial Era and Early Republic.”4
By the 19th century, however, alternative materials like cotton and wood pulp began to take hemp’s place, making it less popular. In 1937, the Marijuana Tax Act was passed, which grouped hemp with marijuana, making hemp sales heavily taxed. The financial strain caused may hemp businesses to close and the hemp industry further declined.5
WWII brought with it a brief boost for hemp, with the U.S. Department of Agriculture (USDA) encouraging U.S. farmers to grow the plant and the government offering subsidies for hemp cultivation. About 1 million acres of hemp were planted in the U.S. during that time, and the stiff fiber was used to make parachutes, uniforms, tarps and other products useful to the war industry.
“After the war ended, the government quietly shut down all the hemp processing plants and the industry faded away again,” the HIA noted.6 The final nail in the coffin came with the passage of the Controlled Substances Act of 1970, which grouped hemp and marijuana together as Schedule 1 substances, a classification reserved for drugs with "high potential for abuse" and "no accepted medical use."
Three years later the Drug Enforcement Agency (DEA) was formed to enforce the newly created drug schedules, and the fight against marijuana and hemp use began.
Marijuana Versus Hemp: What’s the Difference?
While both marijuana and hemp come from the cannabis plant, hemp is low in tetrahydrocannabinol (THC), which is the substance that produces the “high” associated with marijuana use. Whereas hemp typically contains 0.3 percent THC or less, marijuana may contain anywhere from 5 to 35 percent THC, according to HIA.
Interestingly, the 0.3 percent for THC in hemp came about quite by accident when a couple of Canadian scientists designated that number in a 1976 report they wrote on the two plants. Later, the DEA used the same number when they were formulating rules to ban hemp and all products with THC in them. The 0.3 percent later became part of federal law with the 2014 Farm Bill, explained later in this article.7
And while the THC percentage varies in marijuana depending on which part of the plant is used, the Alcohol & Drug Institute at the University of Washington says the average THC in marijuana dried leaves and buds in the U.S. can vary from less than1 percent to 20 percent.8
Marijuana is typically used for medicinal or recreational purposes, whereas hemp can be used for a variety of applications ranging from food and medicine to clothing, construction, body care and even plastic. You can’t get high from hemp, but its high CBD content makes it attractive for medicinal purposes.
Further, whereas marijuana must be grown in a carefully controlled atmosphere, hemp is easy to grow and thrives in most climates. Generally speaking, cannabis sativa, which has long and narrow leaves, is grown outdoors and has higher CBD and low THC, producing no psychoactive effects.
Cannabis idica, on the other hand, has shorter, wider leaves, grows best indoors and contains higher THC, which produces the high most recreational marijuana users are after.
However, because many hybrids have been produced, it’s not possible to identify these qualities from plant name alone.9According to the 2014 Farm Bill, hemp refers to cannabis sativa plants containing 0.3 percent or less of THC, and that definition remained unchanged in the 2018 Bill.