# Cannabis ruderalis
**Cannabis ruderalis** Janisch. is a putative third species of the genus *Cannabis*, described in 1924 by the Russian botanist D. E. Janischevsky for short, wild plants of central Russia that lacked the domestication traits of cultivated hemp and drug cannabis[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A582737-1) • [2](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/inline-files/Williams%20et%20al.%20-%20Industrial%20Hemp%20as%20a%20Modern%20Commodity%20Crop%281%29_0.pdf). Most modern authorities treat the name as a synonym of *Cannabis sativa* L., the single species of the genus, but the term remains in wide use for day-neutral, [autoflowering cannabis](https://www.edgepedia.org/autoflowering-cannabis) and for the wild-type plants from which that trait is thought to derive[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A582737-1) • [3](https://journals.sagepub.com/doi/10.1089/can.2018.0039).
| Key fact | Detail |
|---|---|
| Author and date | First published by Janischevsky in 1924, in *Uchen. Zap. Saratovsk. Gosud. Chernyshevskogo Univ.* 2(2): 14[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A582737-1) |
| Status at Kew | Treated as a synonym of *Cannabis sativa*; accepted at species rank only under alternative taxonomies[1](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A582737-1) |
| Vernacular criteria | "Ruderalis" is applied to plants showing one to three of: CBD roughly equal to THC, wild-type morphology, or early day-neutral (autoflowering) flowering[3](https://journals.sagepub.com/doi/10.1089/can.2018.0039) |
| Signature trait | Photoperiod-insensitive flowering, genetically mapped to at least two loci, Autoflower1 and Autoflower2, in the *C. sativa* gene pool[4](https://pubmed.ncbi.nlm.nih.gov/38625758/) |
| Putative origin | High-latitude populations, theorized to have originated in Siberia[5](https://onlinelibrary.wiley.com/doi/full/10.1111%2Ftpj.16769) |
| Drug content | Described by Schultes and colleagues (1974) as a short, unbranched roadside plant with minimal drug content[6](https://www.euda.europa.eu/system/files/media/publications/documents/683/web_INSIGHTS_CANNABIS_350894.pdf) |
## Origin of the name and the taxonomic debate
The name was published in 1924 by Janischevsky, a colleague of N. I. Vavilov, who examined differences in the fruits (achenes) between wild and domesticated plants of central Russia and referred domesticated plants to *C. sativa* and wild plants to *C. ruderalis*[7](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/media/documents/Small%20et%20at.%20A%20Practical%20and%20Natural%20Taxonomy%20for%20Cannabis.pdf) • [8](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/inline-files/Williams%20et%20al.%20-%20Industrial%20Hemp%20as%20a%20Modern%20Commodity%20Crop%281%29_0.pdf). In botanical Latin, *ruderalis* means weedy or growing among waste, and refers to plants that are the first to colonize disturbed land[9](https://doi.org/10.1139/gen-2023-0005).
Whether *Cannabis* comprises one species or several has been disputed for a century. Ernest Small and Arthur Cronquist, in their 1976 treatment, argued that all *Cannabis* is diploid, that there appear to be no barriers to successful hybridization within the genus, and that variation is continuous, leading them to recognize a single highly variable species, *C. sativa*, with *C. ruderalis* reduced to synonymy[7](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/media/documents/Small%20et%20at.%20A%20Practical%20and%20Natural%20Taxonomy%20for%20Cannabis.pdf). In their infraspecific scheme, Vavilov's earlier name *C. sativa* subsp. *sativa* var. *spontanea* (1922) has nomenclatural priority over Janischevsky's later *C. sativa* var. *ruderalis* (1924)[10](https://journals.sagepub.com/doi/pdf/10.1089/can.2018.0039?cf-mal-redirected=true). A minority of botanists, following Schultes and colleagues in 1974, have recognized three species: *C. sativa* (tall, used for fiber, seed, or psychoactive purposes), *C. indica* (short, wide-leafed, resinous), and *C. ruderalis*[6](https://www.euda.europa.eu/system/files/media/publications/documents/683/web_INSIGHTS_CANNABIS_350894.pdf). Chemotaxonomic work by Hillig and Mahlberg (2004) instead indicated that *C. ruderalis* is a form of *C. sativa*, and later genomic studies were not able to distinguish *C. sativa*, *C. indica*, and *C. ruderalis* from each other, findings that lend support to the single-species view[8](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/inline-files/Williams%20et%20al.%20-%20Industrial%20Hemp%20as%20a%20Modern%20Commodity%20Crop%281%29_0.pdf) • [9](https://doi.org/10.1139/gen-2023-0005).
## What the term means in practice
Because the formal name is a synonym, "ruderalis" today functions mainly as a vernacular label. McPartland's 2018 review of cannabis systematics notes that the term is applied to plants exhibiting one to three characteristics: a cannabinoid profile in which CBD is roughly equal to THC, wild-type morphology, or early flowering, sometimes called autoflowering, meaning day-neutral flowering that is not induced by the light cycle[3](https://journals.sagepub.com/doi/10.1089/can.2018.0039). The label covers a diverse range of plants, including recent hybrids, and does not map cleanly onto formal subspecies[11](https://www.sciencedirect.com/science/article/abs/pii/B9780443154898000013).
## Autoflowering genetics
The trait most associated with ruderalis is photoperiod insensitivity. *Cannabis sativa* is normally a short-day plant whose flowering is controlled by day length, but some plants flower in response to maturity regardless of photoperiod, a trait proposed to have been introgressed from high-latitude populations classified by some as *C. ruderalis*[12](https://pmc.ncbi.nlm.nih.gov/articles/PMC9533707/). The trait has been suggested to be inherited in a simple recessive Mendelian fashion, though peer-reviewed data on this have been limited[12](https://pmc.ncbi.nlm.nih.gov/articles/PMC9533707/).
Recent genetic mapping has given the trait a concrete basis. Genotyping of mapping populations and a diversity panel confirmed a correlation between alleles of the *CsFT1* gene, an ortholog of the flowering-time gene FLOWERING LOCUS T, and photoperiod response, and affirmed that at least two independent loci, named Autoflower1 and Autoflower2, are involved in the photoperiodic control of flowering in the *C. sativa* gene pool[4](https://pubmed.ncbi.nlm.nih.gov/38625758/). Dowling and colleagues identified Autoflower2 as the locus harboring *CsFT1*, and noted that cultivars such as 'Russian Auto CBD', selected from Russian landraces, may carry an Autoflower2 allele derived from the putative *C. ruderalis*, which is theorized to have originated in Siberia[5](https://onlinelibrary.wiley.com/doi/full/10.1111%2Ftpj.16769). A separate study reported a splice site mutation in the *CsPRR37* gene in autoflowering cultivars, indicating that more than one molecular route to day-neutral flowering exists[13](https://www.mdpi.com/2077-0472/15/15/1635).
## Use in breeding
Breeders cross photoperiod-sensitive and photoperiod-insensitive cultivars to produce hybrids that flower under extended photoperiods while retaining enhanced vegetative development, and autoflowering lines are used to shorten the crop cycle[13](https://www.mdpi.com/2077-0472/15/15/1635). In agronomic trials, photoperiod-insensitive (autoflowering) hemp has shown different growth patterns from photoperiod-sensitive types, with the latter generally producing larger plants[14](https://journals.ashs.org/downloadpdf/view/journals/hortsci/59/12/article-p1795.pdf).
## References
1. [Cannabis ruderalis Janisch., Plants of the World Online, Royal Botanic Gardens, Kew](https://powo.science.kew.org/taxon/urn%3Alsid%3Aipni.org%3Anames%3A582737-1)
2. [Small, E. & Cronquist, A. (1976). A Practical and Natural Taxonomy for Cannabis. Taxon 25(4): 405-435](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/media/documents/Small%20et%20at.%20A%20Practical%20and%20Natural%20Taxonomy%20for%20Cannabis.pdf)
3. [McPartland, J. M. (2018). Cannabis Systematics at the Levels of Family, Genus, and Species. Cannabis and Cannabinoid Research](https://journals.sagepub.com/doi/10.1089/can.2018.0039)
4. [A FLOWERING LOCUS T ortholog is associated with photoperiod-insensitive flowering in hemp (Cannabis sativa L.), PubMed](https://pubmed.ncbi.nlm.nih.gov/38625758/)
5. [Dowling et al. (2024). A FLOWERING LOCUS T ortholog is associated with photoperiod-insensitive flowering in hemp. The Plant Journal](https://onlinelibrary.wiley.com/doi/full/10.1111%2Ftpj.16769)
6. [Chapter 1: Botany and cultivation of cannabis, EMCDDA Insights](https://www.euda.europa.eu/system/files/media/publications/documents/683/web_INSIGHTS_CANNABIS_350894.pdf)
7. [Identification and mapping of major-effect flowering time loci Autoflower1 and Early1 in Cannabis sativa L., PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC9533707/)
8. [Williams, D. W. (ed.). Industrial Hemp as a Modern Commodity Crop, ASA/CSSA/SSSA](https://hemp.ucdavis.edu/sites/g/files/dgvnsk12601/files/inline-files/Williams%20et%20al.%20-%20Industrial%20Hemp%20as%20a%20Modern%20Commodity%20Crop%281%29_0.pdf)
9. [Genomics-based taxonomy to clarify cannabis classification, Genome](https://doi.org/10.1139/gen-2023-0005)
10. [Cannabis Systematics at the Levels of Family, Genus, and Species (PDF)](https://journals.sagepub.com/doi/pdf/10.1089/can.2018.0039?cf-mal-redirected=true)
11. [Exploring the historical, botanical, and taxonomical foundations of cannabis: A review, ScienceDirect](https://www.sciencedirect.com/science/article/abs/pii/B9780443154898000013)
12. [Leckie et al. Identification and mapping of major-effect flowering time loci Autoflower1 and Early1 in Cannabis sativa L., PMC](https://pmc.ncbi.nlm.nih.gov/articles/PMC9533707/)
13. [Current Context of Cannabis sativa Cultivation and Parameters Influencing Its Development, Agriculture (MDPI)](https://www.mdpi.com/2077-0472/15/15/1635)
14. [HortScience 59(12):1795-1799 (2024)](https://journals.ashs.org/downloadpdf/view/journals/hortsci/59/12/article-p1795.pdf)
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*Topic: Encyclopedia › Life and health › Plants and algae › Seed plants › Other flowering plants › Rosids › Rosales, Fagales, and Cucurbitales*
*Initially written Sep 17, 2026 · Reviewed: Sep 30, 2026; Oct 21, 2026 · Edited: Oct 15, 2026; Oct 21, 2026 · Last review: Oct 21, 2026*
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