Family: Poaceae |
Jacques Cayouette and Stephen J. Darbyshire Plants perennial; rhizomatous, sometimes producing aquatic leaves when submerged. Culms (5)10-100 cm, erect, glabrous, rooting at the lower nodes; nodes glabrous. Sheaths of aquatic leaves closed to near the apices, translucent, pale pinkish-brown; collars inconspicuous; ligules acute; bladespinkish-brown. Sheaths of aerial leaves usually closed for over 1/2 of their length, sometimes open to the base, opaque, green to olive-green, glabrous; collars conspicuous as a zone of contrasting color; auricles absent; ligules membranous, truncate, lacerate; blades usually flat, glabrous, upper blades conspicuously longer than the lower blades. Inflorescences open panicles; branches stiff and ascending to pendulous, glabrous. Spikelets pedicellate, somewhat laterally compressed; florets (1)2-7(9); rachillas prolonged beyond the uppermost floret, glabrous; disarticulation above the glumes. Glumessubequal, broadly lanceolate to ovate, membranous to subcoriaceous, glabrous, 1-3(-5)-veined, acute to obtuse; calluses short, blunt, bearded to almost glabrous; lemmas ovate, glabrous, membranous to subcoriaceous, with 3(5) obscure veins, apices entire, obtuse; paleas subequal to the lemmas; lodicules2, free, glabrous, toothed or entire; anthers 3; ovaries glabrous. Caryopses falling free; hila broadly ovate, 1/6-1/5 the length of the caryopses. x = 7. From the Greek arktos, north, and philia, loving. SELECTED REFERENCE Aiken, S.G. and R.A. Buck. 2002. Aquatic leaves and regeneration of last years straw in the arctic grass Arctophila fulva. Canad. Field-Naturalist 116:81-86; Brysting, A.K., M.F. Fay, I.J. Leitch, and S.G. Aiken. 2004. One or more species in the arctic grass genus Dupontia? A contribution to the Panarctic Flora project. Taxon 53:365-382. |