View photos of the edible plant Cyperus fendlerianus (Fendler’s nutgrass), profiled in Wild Edible Plants of Arizona.

A passage from Wild Edible Plants of Arizona:

Each stem is anchored by a shallow cluster of fibrous roots. Attached to the small root crown are one to several (usually) corn–kernel sized bulblets (I call them niblets). These starchy and mild–sweet tasting pieces are fine consumed raw – after cleaning them up a little by scraping off their external–brown protective layer.