stout, perennial marsh grasses, rootstock spongy. Culms simple or sparsely branched.
Leaf-blades very long, leaf-sheaths broad, laterally compressed, ligule narrow.
Inflorescence a thyrsiform panicle, rachis long, stout, branches numerous,
clustered or whorled. Spikelets falling entire with pedicels, closely
imbricate, secund, biseriate, rachilla jointed and disarticulating, florets
4-20, perfect; glumes stiff, awn subulate, 1-nerved; lemmas keeled, subulate,
3-nerved; paleas subequal to lemmas, with closely-spaced, ciliate keels. Stamens 3, styles united at base. Caryopsis
with large embryo, obliquely ovoid.