Australian Tropical Rainforest Plants - Online edition

Urochloa pubigera (Roem. & Schult.) R.D.Webster


Webster, R.D. (1987) The Australian Paniceae (Poaceae) : 250.

Common name

Arm Grass Millet


Annual. Culms decumbent, 20-60 cm long and 3-6 -noded. Culm-nodes pubescent.


Leaf-sheaths with hairy outer margin. Ligule a fringe of hairs 0.7-1 mm long. Leaf-blades linear, or lanceolate, 3-18 cm long and 4-16 mm wide. Leaf-blade surface pubescent, hairy on both sides, margins scabrous.


Inflorescence composed of 4-10 racemes borne along a central axis; unilateral, 3-9 cm long bearing 8-30 fertile spikelets on each. Central inflorescence axis 6-18 cm long. Rhachis wingless, angular. Spikelet packing adaxial. Spikelets solitary, or in pairs. Fertile spikelets pedicelled, pedicels oblong, 0.3-0.8 mm long, scabrous. Fertile spikelets comprising of a basal sterile floret and a fertile floret; without rhachilla extension. Spikelets elliptic, or obovate, dorsally slightly compressed, acute, 3.5-4.6 x 1.4-1.7 mm; falling entire. Spikelet callus oblong; incorporating lowest rhachilla internode with adnate lower glume, 0.4-0.8 mm long. Rhachilla internodes elongated between glumes. Glumes dissimilar, reaching apex of florets, thinner than fertile lemma. Lower glume ovate, clasping, 1.7-2.8 mm long; 0.5-0.6 times the length of the spikelet, membranous, without keels and 7-9 -veined. Lower glume surface glabrous, or puberulous. Lower glume apex obtuse. Upper glume elliptic and same length than spikelet, membranous and without keels, 5-7 -veined. Upper glume surface puberulous, apex acuminate. Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume, elliptic, samre length than spikelet; membranous, or cartilaginous, 5-7 -veined, puberulous, acute. Fertile lemma elliptic, 2.5-3.2 mm long, indurate and without a keel. Lemma surface rugulose, margins involute, apex acute. Palea involute, indurate, without keels. Palea surface rugose.


Features not available.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ, CEQ and southwards to south-eastern Queensland. Altitudinal range from near sea level to 860 m. Grows in disturbed places, along roads and gardens in rainforest, riverine forest, Melaleuca forest, vine thicket, Eucalypt woodland and in grassland. Also from India, to Vietnam, Malesia and New Guinea.

Natural History & Notes

A weed of cultivation.

Brachiaria pubigera (Roem. & Schult.) S.T.Blake, Proceedings of the Royal Society of Queensland 81: 5(1969). Panicum pubigerum Roem. & Schult., Systema Vegetabilium Edn. 16 2: 460(1817).
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