|Part of a series on|
Cannabis ruderalis, or C. sativa subsp. sativa var. spontanea, is a low-THC variety or subspecies of Cannabis which is native to Central and Eastern Europe and Russia. Many scholars accept Cannabis ruderalis as its own species due to its unique traits and phenotypes which distinguish it from Cannabis indica and Cannabis sativa; however, it is widely debated by many other scholars as to whether or not ruderalis is a subspecies of Cannabis sativa.
Cannabis ruderalis was first described by Russian botanist D. E. Janischewsky in 1924. The term ruderalis is derived from the Latin rūdera, which is the plural form of rūdus, a Latin word meaning rubble, lump, or rough piece of bronze. In botanical Latin, 'ruderalis' means 'weedy’ or ‘growing among waste.' A ruderal species refers to any plant that is the first to colonize land after a disturbance removing competition.
It is widely accepted C. ruderalis is its own species, rather than a subspecies from C. sativa. It was classified in 1924 by D. E. Janischewsky, noting the visible differences in seed, shape and size from previously classified Cannabis sativa. C. ruderalis represent feral types of Cannabis which have higher CBD levels and a more cerebral effect, this combined with the high THC levels from the C. sativa through hybridization gives the most potent strains.
C. ruderalis occupies regions farther north in latitude. Chemotaxonomic analysis reveals that C. ruderalis is shown to have lower tetrahydrocannabinol levels compared to the feral biotype of C. sativa.
Cannabis ruderalis is smaller than other species of Cannabis. C. ruderalis rarely grows over two feet in height. Plants have "thin, slightly fibrous stems" with little branching. Foliage is typically open with large leaves, C. ruderalis reaches maturity much quicker than other species of Cannabis, typically in a five to seven week period from seed.
Unlike other species of cannabis, Cannabis ruderalis enters the flowering stage based on the maturity of the plant, rather than its light cycle. With C. sativa and C. indica varieties, it is possible to keep the plant in the vegetative state indefinitely by maintaining a long daylight cycle. C. ruderalis, however, will enter the flowering stage regardless of daily light duration. Cannabis geneticists today refer to this feature as "auto-flowering". 
Origin and range
Cannabis ruderalis was first scientifically identified in 1924 in southern Siberia, although it also grows wild in other areas of Russia. The Russian botanist, Janischewski, was studying wild Cannabis in the Volga River system and realized he had come upon a third species. C. ruderalis is a hardier variety grown in the northern Himalayas and southern states of the former Soviet Union, characterized by a more sparse, "weedy" growth.
Similar C. ruderalis populations can be found in most of the areas where hemp cultivation was once prevalent. The most notable region in North America is the midwestern United States, though populations occur sporadically throughout the United States and Canada. Large wild C. ruderalis populations are also found in central and eastern Europe, most of them in Ukraine, Lithuania, Belarus, Latvia, Estonia and adjacent countries. Without human selection, these plants have lost many of the traits they were originally selected for, and have acclimated to their environment.
Cannabis ruderalis has a lower THC content than either C. sativa or C. indica, so it is rarely grown for recreational use and the shorter stature of C. ruderalis limits its application for hemp production. Cannabis ruderalis strains are high in the cannabіnoid cannabidiol (CBD), so they are grown by some medical marijuana users.
However, C. ruderalis' early, plant-age triggered "autoflowering" characteristic (which offers some agricultural advantages over the photoperiodic flowering varieties) as well as its reputed resistance to insect and disease pressures makes it attractive to plant breeders. C. indica strains are frequently cross-bred with C. ruderalis to produce autoflowering plants with high THC content, improved hardiness and reduced height. One strain, identified in 1960, is Cannabis x intersita Sojak which is a cross between C. sativa and C. ruderalis. Attempts to produce a Cannabis strain with a shorter growing season are another application of cultivating C. ruderalis. C. ruderalis when crossed with sativa and indica strains produces a plant which flowers automatically and is fully mature in 10 weeks.
Use in auto-flowering cannabis strains
Because C. ruderalis transitions from the vegetative stage to the flowering stage with age, as opposed to the light cycle required with photoperiod strains, it is bred with other household sativa and indica strains of cannabis to create "Auto-flowering cannabis strains". These strains are favorable for cultivars because they exhibit the hardiness of ruderalis plants while still maintaining the medicinal effects of sativa and indica strains. Cultivators also favor ruderalis plants due to their reduced production time, typically finishing in 3-4 months rather than 6-8 months. The Auto-flowering trait is extremely beneficial because it allows for multiple harvests in one outdoor growing season without the use of light deprivation techniques necessary for multiple harvest of photo-period strains. As a result of ruderalis genetics, auto-flowering plants typically have much higher CBD levels than photo-period cannabis.
Cannabis ruderalis is traditionally used in Russian and Mongolian folk medicine, especially for uses in treating depression. Because C. ruderalis is among the lowest THC producing biotypes of Cannabis, C. ruderalis is rarely used for recreational purposes.
In modern use, C. ruderalis has been crossed with Bedrocan strains to produce the strain Bediol for patients with medical prescriptions. C. sativa and C. indica strains bred with ruderalis plants typically exhibit the "autoflowering" phenotype exhibited by the C. ruderalis lineage, meaning that they flower when the plant reaches a certain maturity (usually ten weeks from seed) as opposed to flowering in accordance with the daily light schedules. In addition to this, due to the typically higher concentration of cannabidiol (CBD), ruderalis plants are valuable for patients looking to treat anxiety or epilepsy. C. ruderalis is also being used as a form of cancer treatment as well as sclerosis and loss of appetite.
- Resin, Harry (9 May 2014). "5 Differences Between Sativa and Indica". High Times. Archived from the original on 16 July 2015. Retrieved 15 July 2015.
- Hillig, Karl W.; Mahlberg, Paul G. (2004-06-01). "A chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae)". American Journal of Botany. 91 (6): 966–975. doi:10.3732/ajb.91.6.966. ISSN 0002-9122. PMID 21653452.
- Stearn, William (2004). Botanical Latin. Timber Press. p. 485. ISBN 9780881926279.
- Ratsch, Christian (1998). Marijuana Medicine: A World Tour of the Healing and Visionary Powers of Cannabis. Translated by John Baker. Switzerland: AT Verlag Aarau. pp. 59–60. ISBN 9780892819331.
- Stafford, Peter (1992). Psychedelics Encyclopedia. Berkeley, California: Ronin Publishing, Inc. p. 159. ISBN 9781579511692.
- Rosenthal, Ed. "Flowering Ruderalis". Cannabis Culture Magazine. Archived from the original on 2 January 2012. Retrieved 16 February 2012.
- Green, Greg (2005). The Cannabis Breeder's Bible: The Definitive Guide to Marijuana Genetics, Cannabis Botany and Creating Strains for the Seed Market. Green Candy Press. p. 14. ISBN 978-1931160278.
- Clarke, Robert Connell (1981). Marijuana Botany: An Advanced Study. Berkeley, California: Ronin Publishing, Inc. pp. 115, 157. ISBN 9780914171782.
- Booth, Martin (2005). Cannabis: A History. Picador. pp. 2–3. ISBN 9781250082190.
- Cervantes, Jorge (2006). Marijuana Horticulture: The Indoor/Outdoor Medical Grower's Bible (5th ed.). Van Patten Publishing. pp. 12. ISBN 9781878823236.
- "Euro Grow". High Times. 12 February 2010. Archived from the original on 16 July 2015. Retrieved 15 July 2015.
- DMT. "The Return of Ruderalis". Cannabis Culture Magazine. Archived from the original on 11 February 2012. Retrieved 16 February 2012.
- "Cannabis Ruderalis". Dutch Passion Seed Company. Retrieved 15 July 2015.
- "What Is Cannabis Ruderalis? | Leafly". Leafly. 2015-06-04. Retrieved 2017-04-21.
- "Cannabis Ruderalis - Seedsman Blog". Seedsman Blog. 2015-01-15. Retrieved 2017-04-21.
- Bienenstock, David (1 March 2011). "Prescription Strength". High Times. Archived from the original on 4 March 2016. Retrieved 15 July 2015.CS1 maint: BOT: original-url status unknown (link)
- "Cannabis Ruderalis". Seedsman Blog. 2015-01-15. Retrieved 2017-04-06.