Glyceria notata, the plicate sweet-grass or marked glyceria, is a species of rhizomatous, tufted, perennial grasses in the mannagrass genus, found in all continents of the world. Its culms are 30–80 cm in height, ascending from a prostrate base, with dark- to bluish-green, flat or folded leaf-blades some 5–30 cm long by 3–14 mm wide. (Wikipedia)