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0.3 percent

Why Hemp Is Defined as Less than 0.3 Percent THC (It’s More Annoying Than You Think)

1969 was a wild year: Nixon was elected president, the Soviets were sending probes to Venus and completing the first space walk in earths orbit, while the Americans would land on the moon. The first Led Zeppelin album was released, the Beatles gave their last public performance, the Stonewall riots occurred. The first ATM was used, the Manson family was running wild, and Woodstock took place. The first episodes of Scooby Doo, the Brady Bunch, and Monty Python all debuted, as did the first colour television broadcast.

Canada and the Le Dain Commission

In this busy year, a little known Canadian named Ernest Small would receive a doctorate from UCLA as a culmination of his studies on plant evolution, and come home to work for the government agency Agricultural and Agri-foods Canada (AAFC).

This is also the year Canada launched the Le Dain Commission to study the issue of cannabis prohibition. A total of 12,000 people would participate in hearings, including John Lennon. Ernest Small would serve as the botanical expert.

After three years, the Le Dain commission recommended that cannabis prohibition be put to an end. During this time, at an experimental farm, Health Canada had also tasked Dr. Small with growing cannabis to study the possibility of providing standardized cannabis for medical use.

Successive Canadian governments would continue to ignore the Le Dain Commission’s findings for the next half a century, while many U.S. states would attempt to decriminalize cannabis.

Dr. Ernest Small would go on to publish numerous books on cannabis (and other plants) over the next decade, but it was the 1976 publication, A Practical and Natural Taxonomy for Cannabis that would prove his most influential.

0.3 Percent: Completely Arbitrary

While his work would go a long way in clarifying that cannabis Sativa, cannabis indica, hemp, and Indian hemp are all in fact the same plant, it would also lead to a new division, labelled cannabis and hemp.

While trying to define subtypes of cannabis, he and co-author Arthur Cronquist (an American scientist well known for his work on taxonomic systems) would settle on THC levels as the key differentiating factor between them.

In their own words: “It will be noted that we arbitrarily adopt a 0.3 percent delta-9 THC dry weight basis in young, vigorous leaves of relatively mature plants as a guide to discriminating two classes of the plant.”

Doctors Small and Cronquist would continue to be very open about their process, freely admitting that this was not the defining boundary between intoxicating and non-intoxicating cannabis. That limit is generally believed to hover around one percent THC.

Limit Leads to Laws

This arbitrary limit would eventually become the legal definition of hemp in Canada in 1998, when the country began licensing commercial hemp cultivators. It would be adopted again by the Farm Bill in the U.S. in 2018. Europe, in an attempt to appear stricter, would (again arbitrarily) adopt a 0.2 percent threshold.

Elsewhere, there is a range of between 0.2 percent, 0.3 percent, 0.5 percent, 0.6 percent, and one percent. One country even specifies that under 0.3 percent is industrial cannabis, 0.3 to one percent is considered recreational cannabis, and anything over one percent is medical.

“It will be noted that we arbitrarily adopt a 0.3 percent delta-9 THC dry weight basis in young, vigorous leaves of relatively mature plants as a guide to discriminating two classes of the plant.”

Dr. Ernest Small and Dr. Arthur Cronquist

Upper limits on THC are also now being sought in some places, and it should be noted that of all these ranges, only the one percent differentiation between intoxicating and non-intoxicating is backed by any kind of actual science.

Nearly a century after cannabis was first criminalized—in Canada it was 1923—the entire world is still choosing to regulate the plant in a non-scientific manner. These arbitrary limits directly affect not only cannabis patients, but hundreds of industries worldwide, and we don’t seem to be anywhere near a common solution.