Japan Flora: Stems 20-75cm. long, erect, firm, simple, evergreen, 3-8 mm. across, shallowly 14- to 26-grooved, scaberulous, the ridges with 2 rows of tubercles, the central cavity about 2/3 the diameter of the stem; sheaths 5.5-14 mm. long, tight, a little longer than broad (3-8 mm. wide), with a black band below the middle and a black border, the teeth 14-26, the apical portion 3-6 mm. long, membranous, dark brown, caducous, the basal portion persistent on the sheath; spikes 6-13 mm. long, sessile. Fruiting Aug.-Dec. Sandy shaded places in valleys and ravines;

Hokkaido, Honshu (n. and centr. distr.). Sakhalin, Kuriles, Korea, Himalayas, Siberia to Europe, and N. America.