Green’s Dictionary of Slang

(Aus. drugs) marijuana.

1977		S.N. Pradhan Drug Abuse.
1986		Spears Sl. and Jargon of Drugs and Drink 39: belyando sprue marijuana. The term is a variant of, or an error for Belyando spew. Sprue is the name of a disease (psilosis) which includes among its symptoms a sore mouth, a raw tongue, and a loss of weight. This also describes the state of some heavy marijuana smokers. Belyando is the name of a river in Queensland, Australia. The spew version refers to the vomiting of Belyando spew (the disease) which is better known medically as gastric spirochetosis [...] The most likely connection is the common name of the disease: grass sickness, where grass (q.v.) = marijuana.
2001		ONDCP Street Terms 3: Belyando spruce — Marijuana.