There's a fair amount of confusion surrounding the botany of Cannabis even among botanists. Until the 1960s, botanists considered that there was only one species of Cannabis: C. sativa, but by 1963 an additional species, C. ruderalis, was considered to have enough distinct characteristics to single it out as a distinct phenotype. Shortly thereafter, Cannabis sativa var. spontanea (large fruited sativas versus fiber sativas) was added as well as C. indica shortly after that. In the last decade most botanists would add the recently defined C. afghani. Today most scientists believe that the species is Cannabis, part of the family Cannabaceae, found in the genus Humulus along with the hops plant. But because of thorough domestication and a long association with humans spanning nearly seven thousand years, the notion that there are individual Cannabis species is not completely agreed upon. Today's popular mixed strains and hybrids and cross-hybrids add further to the confusion.

These different phenotypes or species have also been positively identified on the basis of the psychoactive resin's chemical composition. Indicas generally have higher levels of cannabidiol (CBD) and lower levels of tetrahydrocannabinol (THC) than sativas. Sativas generally have lower levels of CBD and higher levels of THC than indicas. We will come back to these differences in chemical composition later.

How does a botanist identify these different species or phenotypes? If the plant is tall (6-18 feet), with long thin leaves and sparsely branched with long internodes it is C. sativa. Sativas are thought to have originated in a large geographical area running from Central Asia through Central Europe at approximately the 45-50th parallel. If the plant is short (1-2 feet), sparsely branched and auto flowers it is C. ruderalis. Unlike the other Cannabis species C. ruderalis will flower independent of the amount of light provided. C. ruderalis originates in Siberia but can now be found on all the world's continents, including Antarctica. If the plant is short - four feet or less and has short internodes, dense branching with dark green short broad leaves - and its flowering is determined by hours of daylight it is C. indica. Indicas originate from the 30th parallel across the greater Himalayas (Afghanistan, Pakistan, India and Nepal). C. afghani is similar to C. indica but found at 3000 feet in altitude in the mountainous regions of Afghanistan. C. afghani is commonly known as "kush."

Domesticated types, mixed strains and hybrids are subject to the selective pressures of human cultivation and have expanded the possible range of phenotype definition. Today there are some blended indicas that can feel like sativas and blended sativas that have indica characteristics. So what is the medicinal effect of indicas generally? Because of the higher levels of CBD Indicas are superb as muscle relaxants and provide the best full-on analgesic effect. C. indicas are excellent for pain management as it provides the whole-body buzz. Indicas are bronchodilating (they open the airways) and lower one's blood pressure. Indicas are euphoric in nature and can also lower depression. Indicas can increase appetite, but also put one to sleep before they can do anything about it. Indicas make an obviously night time choice for medicating as they are excellent at enhancing sleep.

What typifies the sativa high? The sativa medicinal high is uplifting, stimulating and energetic. No "couchlock" here. Sativa is cerebral in nature ... the mind trips the light fandango and there's a feeling of optimism. They can be great for depression also as long as they don't raise anxiety. Because of sativas' energetic mode they can induce a wee bit of anxiety in some folks, something to watch out for if used for depression. Some sativas that are extremely high in THC can also be spacey or psychedelic in nature. Sativas can also be surprisingly decent for pain, but they operate differently that indicas which gel the body. When using a sativa it is not that you don't still have your pain, but your mind is delightfully otherwise occupied. Sativas are a good choice for daytime medicinal use.

As an FYI - most folks in the Pacific Northwest have not explored the medicinal nature of sativas as well as they have explored indicas. In the Pacific Northwest most the medicinal and street marijuana is grown indoors. Growers, particularly non-patient growers, tend to want to maximize their yields and are most concerned about the almighty dollar. Indicas tend to have shorter growing seasons and are easier to grow and are usually more profitable. Sativas have longer growing seasons and are harder to grow, but in the long run may be more medicinally useful for some patients. Have you had your sativa today?

This story originally published in Mary Jane Magazine #4 , Spring 2011.