2n = 90

2n = 90

Very tall, stout tussock with ivory sheaths and sharp leaves below a shining white culm bearing a large plumose panicle. Leaf-sheath glabrous, ivory beneath epicuticular wax, midrib green. Ligule to 4 mm. Collar dark brown, adaxially clothed in short hairs. Leaf-blade to 2 m × 3 cm; stiff, abaxially long hairy towards margins below, sharply scabrid from many prickle-teeth in upper ⅓, adaxially with thick weft of hairs at base becoming fewer above, minute stiff hairs throughout; margins long (5 mm) hairy below, becoming very scabrid with rows of prickle-teeth. Culm to 4 m, shining, waxy, internodes glabrous. Inflorescence to 1 m, stiff, erect, densely plumose, rachis smooth, branches and pedicels short stiff hairy, long hairs at axils and below spikelets. Spikelets to 25 mm, of 2-3 florets. Glumes equal, to 25 mm, > florets, 1-nerved, acuminate and awn-like above, scabrid. Lemma to 10 mm, 3-nerved, finely scabrid; hairs to 8 mm radiating from base; lateral lobes to 5 mm; central awn to 15 mm. Palea to 6.5 mm, attenuated, keels and apex ciliate, interkeel and flanks hairy. Callus hairs to 1.5 mm. Rachilla to 0.5 mm, glabrous. Lodicules to 0.5 mm. Anthers of ☿ flowers to 4.75 mm, of ♀ flowers to 2.75 mm. Gynoecium: of ☿ flowers ovary to 1 mm, stigma-styles to 1.8 mm; of ♀ flowers ovary to 1.3 mm, stigma-styles to 3.5 mm. Caryopsis to 2.5-3 mm; embryo to 0.75 mm; hilum to 1 mm. 2n= 90.

Plants 4-6 m tall forming dense tussocks; leaf blades ± flat, tapering, up to 3 m long, with several costae prominent, very scabrid in upper part; epidermal silica cells mostly ± round; panicles 60-100 cm long, rather rigid, dense, plumose; glumes 20-35 mm long, lemma awns included; lateral lemma lobes 3-7 mm long.

Gramen perenne, 4-6 m altum, habitu dense caespitosum; f oliorum laminae ± planae, attenuatae, ad 3 m longae, plerisque costis prominentibus, in parte superiore scaberrimae; siliceae epidermidis cellulae plerumque rotundae; paniculae 60-100 cm longae, rigidiores, densae, plumosae; glumae 20-35 mm longae, inclusis lemmatis aristis; laterales lemmatis lobi 3-7 mm longi.