Japan Flora: Rhizomes densely tufted, short, firm, ascending, with stout, yellow, tomentose roots; culms 30-60 cm. long; leaf-blades 3-5 mm. wide, stiffish, glaucous beneath, the basal sheaths bladeless, lustrous, dark red or brown, firm, reticulate-fibrous; spikes 2 or 3, the upper 1 or 2 staminate, linear-clavate, the others pistillate or sometimes with a short staminate portion at the apex, oblong to narrowly obovate, densely flowered, 1.5-3 cm. long, nodding, the lower ones long-peduncled, the bracts 1 or 2, leaflike, not sheathing at base; pistillate scales lanceolate, acute, dark sanguineous, the green, 3-nerved midrib prolonged into an erect awn; perigynia shorter than the scales, 4 to 6(-9) mm. long, erect, narrowly ovate, biconvex, brown- striate, sparsely spinulose, gradually long-beaked, scabrous, deeply bifid or bifurcate at apex, the lobes short, bristlelike; stigmas 2, very long, persistent.  June-July. Rocks in mountains; Honshu (n. to centr. distr. and s. Kinki), Kyushu (Yakushima). Very polymorphic.

var. okuboi (Franch.) Kuek. Spikelets 4-7, contiguous, thick, 1.5-2 cm. long, sessile. Dry sandy mountain slopes; Honshu (Idzu Isis.).