Tochigishiro (Japanese: とちぎしろ) is a cultivar of hemp grown in Tochigi Prefecture, Japan. It meets international standards of non-narcotic agricultural hemp at about 0.2% THC,[2][3] reckoned "remarkably low" by Sensi Seeds.[4] It was grown in the early 20th century at Arlington Experimental Farm near the United States capital.[5] The modern variety was developed beginning in 1973 by Kyushu University professor of pharmacy Itsuo Nishioka from seeds "found in southern Japan",[6] and completed c. 1982 by the Tochigi prefectural government at Tochigi Agricultural Experiment Station in Tochigi-shi.[7][8] According to a National Institute of Mental Health-affiliated researcher, the strain is missing the enzyme tetrahydrocannabinolic acid synthase that makes most Cannabis capable of producing THC.[9] It is the most widely grown cultivar in Japan in the 21st century, being exempt from prohibition under the Cannabis Control Law, due to its low levels of psychoactive chemicals.[10][11] Approximately 90% of the hemp grown in Japan is the Tochigishiro variety (as of 2007).[12]
A research report on an experimental plot at Kitami Agricultural Experimental Station on Hokkaido suggests that it may be the most productive known crop for biomass, yielding 52.7 tonnes/ha in a single season.[13] The crop grows about 3 metres (9.8 ft) tall.[8]
