Sagittaria or "arrowhead"'s a genus of about 20 species of aquatic plants whose members go by a variety of common names, including arrowhead, duck potato, iz-ze-kn, katniss, kuwai (くわい in Japanese), swan potato, tule potato, and wapato (or wapatoo). Several species bear tubers edible as a starchy root vegetable that're collected from the wild or cultivated as crops in North America and East Asia. Description Stock often stoloniferous and tuberiferous. Leaves aerial, floa… (More on Sagittaria)