Chinese cannabis-related stocks have been getting way too high this year for Beijing’s taste, prompting a crackdown to control the investor mania. Marijuana growth and consumption is illegal in China, but cultivation of hemp is allowed in the southern province of Yunnan and in the northern province of Heilongjiang, which legalised the trade in 2010 and 2017 respectively. Though tightly controlled, China is the world’s largest hemp producing country and the biggest exporter of hemp paper and textiles, according to official figures. Hemp contains just a trace of psychoactive component THC, and is used industrially in things like clothing, paper and seed products.