Description: Tufted annuals or perennials often forming large tussocks, sometimes rhizomatous or stoloniferous.
Culms erect or prostrate, slender, unbranched or branched, especially near the base, if so vertical or oblique rhizomes may be formed. Ligule membranous, to 10 mm long or reduced to a short rim with hairs; blade folded in bud, flat, involute or folded, often narrow or bristle-like, tip often blunt and keeled.
Inflorescence an open or contracted panicle. Spikelets solitary, 3–12 mm long, pedicellate, laterally compressed, rachilla disarticulating above the glumes and between the lemmas, 2–several-flowered, the uppermost florets reduced. Glumes acute, keeled, unequal, the lower 1-nerved, the upper 3-nerved, usually shorter than adjacent lemmas. Lemmas keeled, acute, rarely obtuse, 5-nerved, ± hairy on the back towards the base, awnless, callus short often with loose, woolly hairs (‘web’); palea slightly shorter than the lemmas, scabrous or ciliate on the two keels.
Distribution and occurrence: World: A large genus of >200 spp., in temperate and cold climates and extending into the upland tropics. Australia: c. 40 species (c. 34 species native, 6 species naturalized), all States.
Key after Vickery (1970). P. pratensis is planted as a pasture and lawn species; many species are major components of montane and alpine grasslands; a few species are regarded as weeds.
Text by Jacobs, S.W.L., Whalley, R.D.B. & Wheeler, D.J.B.
Taxon concept: Grasses of New South Wales, Fourth Edition (2008).
|
