Culms 1-1.5 m. long, with 7-10 nodes; leaves 7-10 mm. wide, 20-35 cm. long; inflorescence 10-20 cm. long and as broad, the rays and branchlets glabrous; spikelets solitary on each branchlet, narrowly oblong-ovoid, 5-7 mm. long; scales dark gray, about 2 mm. long; brisdes 6, 3-4 times as long as the achene, prominently flexuous, nearly glabrous; anthers 1 mm. long, otherwise with the characters of S, orientalis. Swampy places;
Hokkaido, Honshu (Uzen); rare. Sakhalin, Korea, Siberia, and Europe.