Talk:Cannabis conservation

Talk

Discussion for: Cannabis conservation • View • Links • Related changes

Use this page for verification notes, disputes, and action items. Keep narrative content on the article.

Page scope

Cannabis conservation is the overview above the conservation articles: what is being conserved, the reports of loss and what each stands on, crossing and eradication as threats, who holds the material, the legal limits, the two broad methods and the gaps named in the literature. Definitions of a landrace and how one is maintained belong to Landrace Cannabis. Holdings by number belong to Gene bank. Storage trials and regrowing belong to Ex situ conservation. Reserves, farms and protected areas belong to In situ conservation. Measures of loss belong to Genetic erosion. How outside alleles enter a population belongs to Genetic contamination. Campaigns and their figures belong to Eradication. Treaty terms belong to Genetic resources.

Data verification

Record source conflicts, dating problems and sources not used here. Keep narrative content on the article.

Discussion

Sources

• McPartland and Small (2020), PhytoKeys 144: 81–112; Welling and colleagues (2016), Frontiers in Plant Science 7: 1113; Clarke and Merlin (2016), Critical Reviews in Plant Sciences 35: 293–327; Small and Marcus (2002), in Trends in New Crops and New Uses: the reviews that report loss.
• Ren and colleagues (2021), Science Advances 7: eabg2286; Lynch and colleagues (2025), Nature 643: 1001–1010; Balant and colleagues (2025), Plants, People, Planet 7: 1771–1788: wild-growing plants and sampling.
• Chouvy and Afsahi (2014), International Journal of Drug Policy 25: 416–423; Chouvy (2024), International Journal of Drug Policy 129: 104479; Bachir and colleagues (2022), Cannabis and Cannabinoid Research 7: 603–615; Benkirane and colleagues (2024), Genetic Resources and Crop Evolution 71: 2037–2051: Morocco.
• Canavan and colleagues (2022), Biological Conservation 274: 109709; Aina and colleagues (2025), Scientific Reports 15: 20423; Ford and colleagues (2024), Ecology and Evolution 14: e11325: feral stands.
• Food and Agriculture Organization (2010, 2014); Convention on Biological Diversity (1992); International Treaty on Plant Genetic Resources for Food and Agriculture (2001); Single Convention on Narcotic Drugs (1961); Bellon and colleagues (2017), Evolutionary Applications 10: 965–977; Maxted, Magos Brehm and Kell (2013): the general frame.

Who is making the case

The reviews that call for conservation are written largely from the side of use. Welling and colleagues' title speaks of fast-tracking cultivar development, and one of its authors worked at Ecofibre, whose collection the review describes. McPartland's affiliation in the 2020 paper includes GW Pharmaceuticals. Aina and colleagues and Ford and colleagues work on collecting for the American hemp repository. Clarke and Merlin's section on seed banks quotes Watson and Clarke's call to act "before it is too late".

Varieties, genes and purity

Words such as "extinct", "pure", "contaminated" and "corrupted" are the authors'. McPartland and Small use "corrupted" of landraces in their centres of diversity, and Bachir and colleagues use "contaminated" of Moroccan varieties. Chouvy holds that kif remains distinct after earlier crossing.

Clarke and Merlin say both that "the majority" of landraces are no longer grown and that "the vast majority" may already be extinct. The first is about cultivation and the second is about survival. Neither comes with a count.

What the reports stand on

Hillig's 2004 study of the Vavilov collection appears through Clarke and Merlin, who cite it. McPartland and Small's comparison of THC to CBD ratios sets landrace accessions collected in the 1970s to the 1990s beside later accessions labelled "Indica" and "Sativa"; these are different samples, so it does not follow one population. Benkirane and colleagues' markers compare two populations and give no earlier sample. Halpin-McCormick and colleagues' projections use climate variables and describe where the plant could grow.

Small and Marcus's statement that eradication has "exterminated many of the naturalized populations in North America" and Canavan and colleagues' observation that feral populations remain can both be true, since neither says how many populations existed before. Neither paper measures genetic diversity before and after a campaign.

Whether plants are wild

McPartland and Small name two wild-growing varieties and allow that aboriginal populations may not have survived. Welling and colleagues think few if any intact wild populations exist. Ren and colleagues read the feral plants they sampled as escapes and suggest that pure wild progenitors have gone extinct, while noting that more sampling is needed in key areas. Lynch and colleagues read parts of Asian hemp genomes as pointing to undiscovered wild relatives. Feral and ruderal Cannabis takes the question further.

Whether a programme exists

Documented work on cannabis is mostly on stored collections: the Geneva collection, the Vavilov Institute's regrowing and freezing trials at the University of Mississippi. Welling and colleagues' "virtual" core collection is a proposal. The reviews by Welling, Clarke and McPartland and their colleagues describe no reserve or on-farm project for the plant, which is a statement about those works. Moroccan licences for the local variety have stated aims of supply and of help to growers; the reports do not call them a conservation programme.

Figures

Holdings change quickly and cannot be added across holders, since one lot can sit in two gene banks. No total can be drawn from them. Clarke and Merlin's figure for Svalbard dates from 2016. Their remark that many accessions hold fewer than 1,000 viable seeds is general and names no holder.

Picture of the seed bottle

The bottle photographed at Thanalmalwila has a wrapped metal cap and holds seed with scraps of dry leaf. It has no cork, and the text description of the picture now says what it shows.