Humans have used cannabis for at least 5,000 years as seeds were found in Siberian burial mounds built in 3000 B.C. In the 18th century, European scientists noticed different species inside the cannabis genus. Swedish botanist Carl Linnaeus gave European hemp the official name Cannabis sativa in 1753. Thirty-two years later, French biologist Jean-Baptiste Lamarck noted that plants from India had different physical characteristics from sativa and gave them the classification Cannabis indica. In 1924, Russian botanist D.E. Janichevsky identified a rare species he called Cannabis ruderalis, though some researchers suspect this plant is a hybrid of the other two. Over the years, farmers have crossbred the two species together and created countless hybrid strains falling into three general categories: sativa-dominant, indica-dominant and 50/50.

Differences in Physical Characteristics

Sativas are typically tall and thin and can grow up to six feet indoors and 20 feet outside, whereas indicas are short and stout and grow only two-to-four feet making them better suited to indoor cultivation. Sativas have many long branches with narrow leaves that are typically a lighter green, while indicas have fewer, shorter branches with wider blades. Sativas take 10-to-16 weeks to grow, sometimes even 20 weeks, whereas indicas mature in eight-to-12 weeks. Ruderalis is the shortest plant of all, usually reaching only two feet, with the least amount of leaves. Tetrahydrocannabinol (THC) and cannabidiol (CBD) are two important chemical ingredients found in cannabis, with THC being the substance primarily responsible for the psychoactive effects. Ruderalis holds very little THC, which is one of the main reasons why it never became popular.

Geographic Origination of the Strains

Many experts believe cannabis first appeared in the Central Asian regions of Mongolia and southern Siberia. Sativa thrived in warmer climates closer to the equator in Southeast Asia, Africa, Thailand, Mexico and Colombia. The indica species flourished in the Hindu Kush mountain range that runs from Afghanistan to Pakistan, and made it to Morocco, Nepal and Turkey. Indica survived the cooler weather and high altitude by generating a protective coat of resin. One reason growers created hybrids of sativa with indica was so that sativa could live in harsher climates. The ruderalis species is the hardiest of them all. It originated in central Russia but grows everywhere from the Himalayas to Eastern Europe.

The Benefits and Effects

Sativa offers a more energetic and cerebral high that often promotes creativity. It is the more social choice, good for deep conversations and laughter, and better suited for daytime use. Sativa often has a higher percentage of THC, and clinical studies suggest that certain strains can potentially help treat depression, fatigue and attention deficit hyperactivity disorder (ADHD).
Indica, on the other hand, is better suited for relaxation and stress relief in the evenings. Indica tends to have a higher percentage of CBD, which has valuable antiepileptic, anti-inflammatory and neuroprotective effects. Compared to the head high of sativa, indica produces more of a body high that helps with chronic pain, muscle spasms and nausea. The sedative properties often induce sleepfulness and can help with insomnia, sleep apnea and anxiety.
Hybrids often achieve a balance between the two. For instance, a sativa-dominant hybrid may be cerebral and stimulating while still relaxing the body, and an indica-dominant hybrid can provide higher CBD levels and sedation without putting the person to sleep. The effects ultimately vary according to the strain and the user’s biochemistry.