Cannabis is the botanical name of a genus of annual flowering plants in the Cannabaceae family. There are over 150 species and 11 genera included in the family. The hop plant, often utilized in the production of beer, is another member of the Cannabaceae family.
When grown under favorable conditions, some strains of Cannabis produce fairly large amounts of a chemical known as tetrahydrocannabinol, a cannabinoid commonly called THC. Cannabis grown for its THC content is commonly referred to as marijuana.
Occasionally plants in the Cannabis genus are referred to as hemp. However, the term hemp is more appropriately reserved to describe low THC content Cannabis that is cultivated for purposes like CBD oil, fiber, fuel, lubricants, etcetera, as opposed to THC content.
The Cannabis genus is made up of three species, they are:
Cannabis indica and Cannabis sativa can both be cultivated for their THC content, and are employed to produce substances that include marijuana, hashish, hash oil.
Cannabis ruderalis is rarely, if ever, cultivated for its THC content. However, ruderalis plants are sometimes crossed with indica and sativa plants that are cultivated for their THC content.
Although Cannabis indica and Cannabis ruderalis are sometimes scientifically classified as subspecies of Cannabis sativa, there are some differences in these plants that make them worthy of being considered as three totally separate species.
Image: Cannabis sativa
Author: Prof. Dr. Otto Wilhelm Thome
From: Flora von Deutschland, Osterreich und der Schweiz
Source: Wikimedia Commons
Cannabis indica originated in Asia, further from the equator than C. sativa. It is now cultivated in most parts of the globe. For centuries in Asia, especially areas that surround the Himalayas, Cannabis indica has been cultivated by humans to produce hashish.
When allowed to grow freely, an indica plant seldom exceeds 7 feet/2 meters in height. Cannabis indica plants take less time to mature and need less light than sativa plants.
Cannabis indica strains don't get as tall as Cannabis sativa strains but they are more bushy. A short Cannabis indica strain is well suited to growing in an area where height is a consideration, like when being grown indoors.
Cannabis sativa probably originated in Asia, relatively close to the equator. It is now cultivated in most parts of the globe. When grown outdoors, some Cannabis sativa plants can attain a height of 20-26 feet/6-8 meters.
Cannabis sativa plants cultivated to produce marijuana, are generally higher in THC than indica plants. This means marijuana from a mainly, or pure, Cannabis sativa strain will produce a stronger high, when compared with a similar weight of marijuana from a Cannabis indica plant.
Cannabis sativa plants need more light and take more time to mature than indica plants, they are better suited to growing outdoors. Although, there are strains with some sativa heritage that can be grown indoors.
Cannabis ruderalis originated from stray Cannabis sativa seeds that were employed in the production of hemp, and grew wild.
It can be found growing wild across the globe, often in patches and along roads near places where hemp was once cultivated. These wild plants are commonly referred to as ditch weed.
Cannabis ruderalis doesn't grow tall, usually 3 feet/0.9 meters or less. It can grow in harsh climates that would stunt or kill indica and sativa plants.
It will flower according to its age regardless of photoperiod, the plants daily exposure to light. Both Cannabis indica and Cannabis sativa require a shorter day to trigger flowering.
Though not cultivated for its THC content, some breeders have crossed sativa and indica strains with ruderalis to produce auto-flowering marijuana strains.
Auto-flowering marijuana strains are those that start to flower when the plant gets to a certain age, rather than requiring shorter days to induce flowering.
Cross - Plants of two distinct types that are bred to produce a new distinct type of plant, called a hybrid. Crosses are attempted in order to isolate desired characteristics of the parent plants while eliminating or minimizing undesired characteristics.
Cultivate - To encourage plant growth by providing enriched growing conditions.
Genus - Genus, plural form genera, is a rank that families are divided into based on similar characteristics. In the case of marijuana plants Cannabis is the genus. Species that make up the Cannabis genus are Cannabis indica, Cannabis ruderalis, Cannabis sativa.
Hemp - Cannabis plants that are cultivated for purposes other than THC content. Some laws are based on considering a Cannabis plant with THC levels below a certain threshold, to be a hemp plant.
Hybrid - A marijuana hybrid is produced by crossing two genetically different plants. A hybrid is bred for specific traits that the breeder desires.
Marijuana - Cannabis plants that are bred and cultivated to have a high THC content. Most strains grown as marijuana are capable of producing marijuana with an 8%-14% THC content, by weight. More potent strains can reach 15%, or higher.
Plant Variety - A plant variety is a legal term that gives plants that possess unique qualities some protection under the law. Similar to a copyright. In some countries where marijuana is illegal, marijuana strains can't be classified as plant varieties for protection, because they are illegal.
sp. and spp. - Unknown or undisclosed species may be referred to using the abbreviation sp. (singular) or spp. (plural) in place of the specific species name(s). The term Cannabis sp. would mean 1 unknown or undisclosed species from the Cannabis genus. The term Cannabis spp. could mean the entire genus, or 2 or more unknown or undisclosed species from the genus.
Species - Species is a rank that genera are divided into based on similar characteristics. A species is a group of living entities that are reproductively isolated, share a common gene pool, and a common niche. Some people consider the Cannabis genus is made up of three species. Other people consider the Cannabis genus is made up of one species called Cannabis sativa, with Cannabis indica and Cannabis ruderalis as subspecies.
Strain - The term marijuana strain is used to indicate a group of marijuana plants that have developed characteristics that make them different, when compared to other marijuana strains. The term strain has no legal status but it is commonly used by marijuana growers and breeders to differentiate between plants that are grown for their THC content. Examples of marijuana strains are big bud, haze, white widow.
Subspecies - Subspecies is a rank below that of species. A subspecies is a group of living entities that differ from the species itself, and if applicable, other such subdivisions within that species.
Variety - Variety is a type of living entity that has developed an appearance distinct from other varieties in the species it came from, but will hybridize freely with other varieties in the same species. Varieties often develop in nature as a result of being geographically separated, for a long period of time, from the species of plant they originated from. Varieties can also be mutant plants. Not to be confused with the legal term plant variety. Some people use the term marijuana variety in place of marijuana strain.