Taxonomy of Cannabis
"The biological (reproductive) definition of a species states that all specimens of a population are of a single species if they are naturally able to sexually reproduce, generating fertile offspring. This is the case throughout the genus Cannabis, and by this definition, therefore, there are no clear biological grounds to separate it into different species.However, within the species Cannabis sativa L., several subspecies are sometimes identified (Small and Cronquist, 1976).
"Despite this, modern Cannabis taxonomy remains confused, as a scientific minority prefers to define species according to their typological or morphological characteristics. In 1974, Schultes et al. described three putative species, Cannabis sativa L. (a typically tall species used for fibre, seed or psychoactive use), Cannabis indica Lam. (a short, wide-leafed plant from Afghanistan, used to produce resin) and Cannabis ruderalis Jan. (a short unbranched roadside plant with minimal drug content)."
"EMCDDA Insights: Cannabis production and markets in Europe," European Monitoring Centre for Drugs and Drug Addiction (Lisbon, Portugal: 2012), p. 21.