Japan Flora: Sterile sterns 20-80 cm. long, erect or decumbent at base, green, 3-4 mm. across, the internodes nearly smooth or with minute scabrid tubercles, 6- to 15-grooved, the central cavity less than half the diameter of the stem; primary sheaths 3-6 mm. long, green, the teeth as many as the grooves, subulate, acuminate, brown throughout; branches spreading, simple, verticillate, (3-)4-grooved, the sheaths pale green, 3- or 4-toothed, the teeth subulate-triangular, acuminate, black-tinged at the tip; fertile stems 10-30 cm. long, smooth, terete, simple, flesh-colored to pale brown, the sheaths 10-25 mm. long, loose, pale green to brownish, 6- to 12- toothed; spikes 2-4 cm. long, pedunculate. Fruiting Mar.-June. Sunny banks and waste grounds in lowlands to mountains;

Hokkaido, Honshu, Shikoku, Kyushu; very common. Circumboreal.