Marijuana strains
Cannabis strains are either pure or hybrid varieties of the plant genus Cannabis, which encompasses the species C. sativa, C. indica and C. ruderalis.
Varieties are developed to intensify specific characteristics of the plant, or to differentiate the strain for the purposes of marketing or to make it more effective as a drug. Variety names are typically chosen by their growers, and often reflect properties of the plant such as taste, color, smell, or the origin of the variety. Cannabis strains commonly refer to those varieties with recreational and medicinal use. These varieties have been cultivated to contain a high percentage of cannabinoids. Several varieties of Cannabis, known as hemp, have a very low cannabinoid content, and are instead grown for their fiber and seed.
Relative size of cannabis types
The two species of the Cannabis genus that are most commonly grown are Cannabis indica and Cannabis sativa. A third species, Cannabis ruderalis, is very short and produces only trace amounts of tetrahydrocannabinol (THC), and thus is not commonly grown for industrial, recreational or medicinal use. However, because Cannabis ruderalis flowers independently of the photoperiod and according to age, it has been used to breed autoflowering strains.
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