Plants shrublike to arborescent, in open or dense, spreading clumps or thickets; rhizomes leptomorphic. Culms 3-10(20) m tall, 3-10(15) cm thick, self-supporting, erect or nodding, diffuse or pluricespitose, rarely solitary; nodes slightly swollen; supranodal ridge prominent; internodes strongly flattened for their whole length, doubly sulcate above the branches, glabrous, smooth. Branches 2(3) per midculm node, unequal, initially erect, becoming deflexed, basal internodes not compressed. Culm leaves coriaceous, very quickly deciduous; blades usually strap-shaped and narrow, usually reflexed. Foliage leaves: sheaths deciduous; blades small to medium-sized, usually glossy and thickened, indistinctly cross veined. Inflorescences open or congested, sometimes spicate to subcapitate, fully bracteate, bracts usually bearing a small blade at the apex. Spikelets or pseudospikelets with 2 to several florets, the uppermost rudimentary. Lemmas lanceolate; paleas not exceeding the lemmas, strongly to very weakly 2-keeled, often bifid; anthers 3; styles or style branches 3. x = 12. Name from the Greek phyllos, 'leaf', and stachys, 'spike', referring to the reduced blades often seen on persistent bracts proximal to the spikelets.
