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further classified as: Cannabis sativa (= C. sativa var. sativa), Cannabis indica (= C. sativa var. indica), Cannabis ruderalis (= C. sativa var. spondanea), Cannabis afghanica (= C. sativa var. afghanica). Each has distinct growth patterns, look, smell, taste, etc.
Cannabis Sativa
    Cannabis sativa (= C. sativa var. sativa), originated predominately in Asia, the Americas, and Africa. Each area of origin has specific characteristics, but all have the following general traits: tall, leggy stature with spacious internodal length, a large sprawling root system, large narrow-bladed leaves, and somewhat sparse flowers when grown indoors under lights. Sativas bloom several weeks to months later than indica strains. While good producers outdoors, often growing to 15 feet (4.5 m) or more, indoors pure sativa strains often grow too tall too fast—some up to ten feet in three months-to be practical for grow room cultivation. An HID bulb is unable to efficiently illuminate tall plants, and the yield-per-watt-of-light or yield-per-square-foot-of-space is very low. Mexican, Columbian, Thai, and Jamaican strains can be very potent, with a high THC to CBD ratio that produces a soaring, energetic, “speedy” high. But potency can also be minimal, with low levels of THC. Most exported Columbian, Mexican, Thai, and Jamaican marijuana is poorly treated throughout life and abused when dried and packed. This abuse causes more rapiddegradation of THC. Consequently, seeds from fair smoke are often more potent than the parent.
    Central African sativas, including the THC-potent ‘Congolese’, grow similarly to Columbian strains, with a tall leggy stature, often growing more than 15 feet (4.5 meters) tall with loosely packed buds.
    South Africa has major seaports. Sailors brought Cannabis sativa from many different places and planted it in South Africa. Consequently, potency of South African weed can be very high or very low, and can grow short, tall, leggy, bushy, etc. The famous ‘Durban Poison’ yields potent, pale-green, early buds and is the best-known South African strain.
    Asian sativas, including Thai, Vietnamese, Laotian, Cambodian, and Nepalese, have diverse growth characteristics and vary significantly in potency. While Thai and other sativas from the area are often super THC-potent, they are some of the most difficult to grow indoors and the slowest to mature. Thai strains produce very light, wispy buds after flowering for about four months on plants with large, sprawling branches. Thai, Vietnamese, Cambodian, and Laotian sativas are more prone to grow into hermaphroditic adults.
    Nepalese sativas can grow oversized leaves on tall leggy plants that produce sparse, late-blooming buds, but other strains from this region develop into short, compact plants that bloom earlier. Tetrahydrocannabinol (THC) production and potency is often quite high, but can also be second-rate.
    Hemp strains are all considered to be Cannabis sativa. Hemp, affectionately referred to as “rope,” is Cannabis sativa grown for fiber content. Hemp is often seeded and contains very, very low levels of THC.

This leaf from an industrial hemp plant came from the French entity Chanvre & Co. Industrial “no high” cannabis will pollinate drug cannabis.
Cannabis Indica
    Cannabis indica (= C. sativa var. indica) originated in Pakistan and India. Indica is prized by indoor growers and breeders for its squat, bushy growth; condensed root system; stout stems; broad leaves; and dense, THC-laden, fat heavy flowers. Foliage is very dark green, and in some strains, leaves around buds turn reddish to purple. Short, whitish pistils turn reddish to purplish in hue. A few indicas from this part of the world have narrower leaves, long white pistils, and pale green foliage. Indica strains generally contain a higher ratio of CBD to THC, which causes an effect often described as a heavy, incapacitating “sit-on-your-head” stone. Potency of the “high” ranges from fair to