Stems erect, 2 to 6 ft high, round, 1⁄12 to 1⁄5 in. in diameter, with a very small hollow up the centre; joints rather prominent, from 10 in. apart at the base to about 1 in. near the apex; branches slender, erect. Leaves 11⁄2 to 6 in. long, 1⁄6 to 3⁄4 in. wide, rounded at the base, long and slenderly pointed, glabrous, and of the same shade of brilliant green on both surfaces; bristle-toothed on one margin, minutely so on the other; secondary veins two to four each side the midrib; leaf-sheath with a tuft of erect hairs at the top, and smaller ones on the margin.
Native of Japan; introduced about 1895 by way of France. This bamboo spreads rapidly by means of underground rhizomes, and forms a dense thicket of slender, erect stems of various heights. Its distinguishing marks are in the narrowness of the leaves, their smoothness, and similarity of shade on both surfaces.