Ruderalis

Ruderalis refers to small, weedy, day-neutral (auto-flowering) cannabis populations, named by D. E. Janischevsky (1924) as Cannabis ruderalis from feral populations in the Volga region and Siberia. The epithet derives from Latin rudus/ruderis ("rubble, waste ground"), referencing the plant's ruderal ecology in disturbed habitats. Its defining trait is photoperiod-independent (autoflowering) reproduction, triggered by plant age rather than day length — a trait now widely introgressed into commercial autoflowering cultivars. ⚠️ Taxonomic status is disputed: Schultes et al. (1974) and Hillig (2005) treated it as a distinct species; Small & Cronquist (1976) and McPartland (2018) consider it a feral escape of C. sativa or at most a subspecies (C. sativa subsp. spontanea). Clarke & Merlin (2013) regard many "ruderalis" populations as feralized hemp. Genomic studies (Sawler et al. 2015; Ren et al. 2021) generally support monotypic treatment, though Hillig (2005) identified a distinct Central Asian ruderal gene pool. → See also: Auto-flowering, Landrace.