POACEAE  

Annual, small, tufted, sometimes geniculate. Leaf blade expanded to rolled, almost filiform; ligule a long unfringed membrane. Inflorescence an open panicle, branches capillary and conspicuously divaricate; spikelets solitary, pedicelled; pedicel club-shaped at apex. Spikelet 2-3 mm long, laterally compressed; disarticulating above glumes and between florets; glumes very unequal, shorter than spikelet, awnless; lower glume minute or almost absent, nerveless; upper glume 1-nerved. Florets 2-7, bisexual; lemma similar in texture to glumes, membranous, obtuse to rounded, glabrous, 3-nerved, keeled on all 3 nerves, awnless; callus short, glabrous; palea bilobed, 2-keeled. Lodicules 2. Stamens 3, ovoid. Ovary glabrous; styles plumose. Caryopsis oblong-ellipsoid. x= 6, 7 (polyploidy).

Pedicelled spikelet narrower than sessile spikelet, awnless, male or sterile, or reduced to a glume, awnless. x= 5 (aneuploids, high polyploidy).

Annual or perennial, caespitose or decumbent, sometimes rhizomatous or stoloniferous. Leaf blade expanded or folded, rarely rolled, sometimes pleated longitudinally, occasionally saggitate; ligule a fringed membrane or fringe of hairs. Inflorescence a panicle, open or usually spike-like, then dense and cylindrical with branches reduced to stumps; spikelets solitary or clustered, shortly pedicelled or subsessile, each spikelet or cluster subtended by 1 to many bristles, these persist on axis after spikelet falls, bristles either shorter or longer than spikelet, scabrid, often coloured; spikelets when clustered usually not all fully developed. Spikelet elliptic to oblong to ovate, compressed dorsiventrally, falling with glumes (not disarticulating in cultivated forms); glumes unequal, membranous, awnless; lower glume up to half as long as spikelet, ovate from clasping base, 3-6-nerved; upper glume a third up to as long as spikelet, 3-9-nerved. Florets 2; lower floret male or sterile; lemma as long as spikelet, 5-7-nerved, rounded, flat, or longitudinally grooved dorsally, awnless; palea well developed or minute to 0; upper floret bisexual; lemma firmer than glumes, usually indurated, often finely or coarsely transversely rugose, more rarely smooth and glossy, glabrous, entire, margins inrolled and clasping only edges of palea, awnless; palea similar to lemma, relatively long. Lodicules 2, broadly cuneate. Stamens 3. Ovary ellipsoid, glabrous; styles distinct, plumose above. Caryopsis oblong or ellipsoid. x= 9, 10 (high polyploidy).

Annual or perennial, tufted. Leaf blade linear, expanded or rolled, flaccid; ligule an unfringed membrane. Inflorescence a bristly single spike; spikelets solitary, sessile, distichously imbricate on main axis. Spikelet 10-15 mm long, laterally compressed, falling with glumes (not disarticulating in cultivated species); glumes narrow, unequal, +/- as long as spikelet (excluding awns), strongly keeled, acuminate to awned, upper glume 1-nerved. Florets 2 or 3, bisexual or uppermost floret reduced and sterile; lemma oblong, lanceolate, glabrous, strongly keeled with single median keel on back, 5-nerved, nerves apically nonconfluent, awned; awn usually obvious, straight, glabrous; palea 2-keeled, bidentate, almost equalling lemma. Lodicules 2, hyaline, ciliate. Stamens 3. Ovary obovoid, hairy; styles distinct, plumose above. x= 7.

Perennial or annual, tufted, sometimes decumbent at base, stoloniferous, sometimes rooting from nodes; culms decumbent, more rarely erect. Leaf blade and sheaths usually bearing gland-tipped hairs, often viscid; ligule a fringe of hairs. Inflorescence a panicle, open or contracted; spikelets solitary, shortly pedicelled to subsessile. Spikelet slightly laterally compressed, disarticulating above glumes; glumes unequal to +/- equal, +/- as long as spikelet, similar, membranous, green or grey, glabrous or hairy, hairs sometimes glandular, lanceolate, 7-11(14)-nerved, awnless. Florets 4-9, bisexual; upper 1 or 2 florets usually reduced and sterile; lemma dorsally rounded, firmer than glumes, 9-nerved, subcoriaceous, dorsally long-villous towards base, usually scabrid, 6-lobed, lobes alternating with 5 straight, scabrid awns from between lobes; callus minute, pointed, hairy; palea longer than lemma, oblong or elliptic-oblong, 2-keeled, with narrow flaps, stiffly ciliate along keels, cilia very often with interspersed glandular-tipped hairs. Lodicules 2, minute, cuneate, truncate or often with apex shallowly bilobed with gland-tipped hairs. Stamens 3. Ovary glabrous; styles distinct, plumose. Caryopsis ellipsoid. x= 9 (polyploidy).