A rhizome is an underground plant stem that grows horizontally and performs both nutrient storage and reproduction functions. Unlike roots, rhizomes can generate new shoots and roots at nodes along their length.
Rhizomes that are used as food include ginger, turmeric, galangal, wasabi, lotus root, and horseradish. Asparagus, rhubarb, and taro plants reproduce through their rhizomes, though their rhizomes are not eaten.