Classification of Marijuana (Organic)

According to current scientific consensus, Marijuana is monotypic and consists of a single species Marijuana sativa L. Its closest relative in the plant world is Hops (Humulus lupulus L.), both species together making up the family of the Cannabaceae. Over time, people worldwide have selectively grown Marijuana for certain desired characteristics including narcotic effect, plant size, flower yield, smell and taste, etc. As a result of centuries of breeding and selection, a wide range of Marijuana varieties have been developed. Nowadays, well over 700 varieties have been described and many more are thought to exist. This has led to extensive discussion on further botanical and chemotaxonomic sub-classification. 

For forensic and legal purposes, the most important subclassification is that of the ‘drug type’ (marijuana) versus the ‘fiber type’ (hemp), with an emphasis on the total THC content of the plant. In most parts of the world, hemp varieties are not allowed to contain more than about 0.3% (by weight) of THC in the dried flower tops of the plant (Industrial Hemp Farmers Act of 2015, S. 134).

Until recently, Marijuana products used for medicinal purposes in official programs all belonged to the drug type, because of their high content of delta-9-tetrahydrocannabinol-acid (THCA), that is transformed to the biologically more active THC by heat. However, increasingly Marijuana medication is offered based on cannabidiol (CBD)-rich extracts from hemp type Marijuana that contains cannabidiolic acid (CBDA). The constituents THC, THCA, CBD and CBDA belong to a group of chemical structures called cannabinoids.

Sativa and indica 

Another commonly used subclassification, based more on phenotypic traits, distinguishes sativa from indica types of Marijuana, both regarded as a subspecies of Cannabis sativa L.  According to the botanical description of Marijuana, sativa types were originally grown in the Western world on an industrial scale for fiber, seed oil, and animal feed-stuff. They are phenotypically characterized by tall growth with few widely-spaced branches and long, thin leaves. In contrast, plants of the indica type originated in South Asia and were known historically as Indian hemp. They are characterized by shorter bushy plants and broader leaves, typically maturing relatively fast. Most Marijuana plants that are currently used as drug or medicine are a hybrid (cross-breed) of sativa and indica ancestors. Marijuana-type ruderalis is also recognized as a separate subspecies. It is a smaller and ‘‘weedy’’ plant originally from Central Russia.

Besides the botanical distinction between sativa and indica types of Marijuana, a parallel vernacular system of classifying Marijuana varieties has developed among experienced (recreational) growers and users of Marijuana. Users often talk about ‘strains’ instead of using the botanically more proper term ‘varieties’. This vernacular distinction between sativa and indica strains is an important guide for recreational users and patients alike, and is mainly based on the physical effects the strains cause. Sativa strains are typically characterized as uplifting and energetic. The effects are mostly cerebral (“head-high”), also described as spacey or hallucinogenic. This type gives a feeling of optimism and well-being. In contrast, indica strains are primarily described as calming and grounding (“body-high”). This type is said to cause relaxation, stress relief, and an overall sense of serenity. 

It is currently unclear to what extent the botanical and the vernacular use of the terms sativa and indica are overlapping. Sativa and indica strains tend to have a different smell, which may reflect a different terpene profile. Indeed, a recent study identified terpenes, and not cannabinoids, to explain the major chemical differences between the two types. 

The study suggested that hydroxylated terpenes in the Marijuana plant, including linalool, guaiol, eudesmol, and alpha-terpineol, could be considered as markers for indica strains of Marijuana.