John Cage, in addition to being a prolific writer, composer and artist, was an avid mycologist. His mycological pursuits included: frequent and intensive foraging expeditions, teaching the subject at New York's New School of Social Research, heading multiple official mycology based societies, and of course, cooking mushrooms. In 1959, Cage won five million lire on an Italian TV quiz show with mushrooms as his specialty subject. Artistically, Cage composed numerous poetic and sound-based projects about mushrooms, as well as numerous sketches and watercolors of mushrooms. Cage amassed an impressive collection of books and mycological related ephemera, which he donated to the University of California at Santa Cruz with the express instruction that they be used rather than preserved. The theme and presence of mycology was never far from Cage's mind or heart. They were an artistic muse as well as a Zen teacher for Cage, paradoxically meaningful and meaningless as symbols. This article seeks to explore mushrooms as a possible unifying thread in the often-inscrutable life of one of America's most beguiling artists.