Zizania palustris

About

Wild rice, also called manoomin, mnomen, psíŋ, Canada rice, Indian rice, or water oats, is any of four species of grasses that form the genus Zizania, and the grain that can be harvested from them. The grain was historically and is still gathered and eaten in North America and, to a lesser extent, China, where the plant's stem is used as a vegetable.

Summary from Wikipedia