Green’s Dictionary of Slang

(US black/drugs) marijuana.

c.1995		Obscure Disorder ‘Maintain the Focus’ 🎵 Maintain the focus while we smoke these marijuana trees.
2003		J. Lethem Fortress of Solitude 432: Dose was one of his several mules; the others dealt ‘trees’ — tight-rolled Chiba stick, cut with mentholated tobacco to stretch the ingredient.
2017		Big Shag ‘Man Not Hot’ 🎵 Everyday man's on the block, smoke trees / See your girl in the park, that girl is a uckers.