Talk:Hokkaido

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Discussion for: Hokkaido • View • Links • Related changes

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Page scope

Hokkaido treats the island of Hokkaido and the islands of Rishiri, Rebun and Okushiri as a cannabis growing region: the hemp grown for fibre from the 1870s, its decline after the Second World War, and the self-sown cannabis that is pulled up across the prefecture every year. Japan's law on cannabis is treated at Japan. Hokkaido Prefecture as an administrative unit has no page of its own; if one is written it takes the title Hokkaido Prefecture.

Data verification

Record source conflicts, dating problems and other reports bearing on the region here. Keep narrative content on the article.

Discussion

Why Hokkaido is a growing region

• The Chitose health office of the Ishikari Subprefectural Bureau (page of 27 July 2026) states that the Hokkaido government's campaign against wild cannabis and illicit poppies runs from 1 June to 30 September each year, that about 500,000 plants were removed across the prefecture in fiscal 2025 (令和7年度), and that people are arrested in Hokkaido every year for harvesting wild cannabis.
• The prefecture's industrial-hemp report of March 2014 gives the area under hemp in Hokkaido from 1884 (95 ha) to 1946 (131 ha), from the agricultural statistics of the period, with a peak of about 1,500 ha, and one licensed grower on seven ares in 2011.
• The Hokkaido Shimbun reports the pulling of self-sown plants at Bihoro (about 4,000 plants, July 2025) and Tsubetsu (October 2025).

These sources report Hokkaido as a whole; none of them names a district where hemp was grown or where the self-sown stands are densest. The island and its three islands drawn here cover about 78,500 km².

How the border is drawn

• The line follows the coastlines of the island of Hokkaido and of Rishiri, Rebun and Okushiri, from their OpenStreetMap island outlines (relations 6679920, 4094780, 4094779 and 5738086), so the sea is not drawn in. Smaller islands, all under 25 km², are not drawn.
• The southern Kuril Islands, which Russia administers and Japan claims as part of Hokkaido Prefecture (see Kuril Islands dispute), are not drawn in: none of the sources places hemp or self-sown cannabis there.
• The infobox point (43.39, 142.56) is the centre of the land drawn, not a field.

Growing status

The status is Active: one licensed grower was growing hemp in Hokkaido in 2011, and self-sown cannabis is pulled up across the prefecture every year, about 500,000 plants in fiscal 2025. No source says that the plants have been cleared.

Origin of the self-sown stands

• The Hemp Museum (Tōyō Keizai Online, 13 June 2021, an excerpt from its book Nihonjin no tame no taima no kyōkasho) states that the plants pulled up each year are remnants of the hemp grown as national policy in the Meiji period, and that Hokkaido's first trial planting, in 1871, used seed from Tochigi.
• The final report of KAKEN grant 17K15475 (Yamamuro Tadashi, National Research Institute of Police Science, fiscal 2017–2020) states that wild cannabis in Hokkaido falls into a group completely different from the native Japanese cannabis of Honshu, from 24,135 SNPs in 144 samples.

The grant report does not discuss where the Hokkaido plants came from.

Herbarium sheet inside the line

Anon. 3189 (1885), gathered near Nanae in September 1885, lies inside the line. Its sheet records no cultivation, so it is not listed as an accession of the region.

Accession

ACE-JPN-HOK-0120190001, ACE Seeds' reproduction of a hemp line from Hokkaido, is listed under the region on the seller's statement of origin. The seller's description of Hokkaido as the prefecture that has traditionally grown the most cannabis in Japan is its own; the agricultural statistics in the 2014 report put Hokkaido's hemp at about 1,500 ha at its peak, against more than 20,000 ha nationally, and the Sekai Daihyakka places half the national acreage in Tochigi in the early Shōwa years.

Sources

• Hokkaido Industrial Hemp Feasibility Committee (2014). 北海道産業用大麻可能性検討会, set up by the Agriculture Department of the Hokkaido government in August 2013. Its history of hemp in Hokkaido (p. 2) was presented by the committee's secretariat at its first meeting. The table of acreage gives national and Hokkaido figures for 1884–1965 and cites the agricultural statistics of the Ministry of Agriculture and Commerce and its successor and a history of the Hokkaido flax industry; the Hokkaido column is blank from 1955. The member's remark on self-sown cannabis and the chair's reply are from the minutes of the first meeting (p. 11).
• Ishikari Subprefectural Bureau (2026). A page of the Chitose regional health office; the figure of 500,000 plants is for the whole prefecture, not for the Chitose district.
• Hokkaido Shimbun (2025). Both reports are by Aoyama Hideyuki, datelined Bihoro (16 July 2025) and Tsubetsu (8 October 2025).