Family Description

Annual or perennial; tufted, rhizomatous or stoloniferous. Leaves in basal, vegetative shoots and inserted distichously along stems(culms); blade usually ± linear; sheath open or closed, with a commonly membranous ligule at junction with base of blade. culms herbaceous or woody, jointed, internodes usually hollow. Infls. composed of spikelets. spikelets arranged in a panicle or raceme, racemes sometimes spike-like, parital infls. sometimes substended by bladeless sheaths (spathes). spikelets of distichously arranged bracts, the lower pair (occasionally one absent) sterile, called glumes, and one or more florets, if more than one than inserted along a slender axis (rachilla that may break up (disarticulate), or persist. florets composed of lemma and a usually 2-keeled palea subtending a single flower. flower usually bisexual, ovary with a single ovule, stigma commonly 2, feathery; stamens usually 3 (sometimes 1,2, or 6), subtended by 2 (_3 or ocassionally more) minute scales (lodicules). fruit an indehiscent grain(caryopsis), pericarp sometimes free, ocassionally fleshy.

Genus Description

Perennial or annual, tufted or shortly rhizomatous. Culms unbranched or branch, erect; or decumbent below and rooting from lower nodes. Leaves mainly on culm, blades narrowly oblong, flat, glabrous; ligule membranous. Infl. a panicle, branch to 2 orders, branches whorled. Spikelets pedicelled, borne singly, fertile floret single, bisexual, subtended by two reduced, strile florets each consisting of small, glume like lemma; whole spikelets deciduous above glumes or persistent(in cultivated species), pedicle short, cup-shaped at apex. Glumes represented by microscope swelling at pedicles apex. Sterile lemmas linear to triangular, herbaceous, 1-veined. Fertile floret, lemma conduplicate, acuminate, awned or not, margins claspnig palea, keeled, each side oblong, 5-veined, crustaceous; palea simillar in texture and to lemma(but narrower), conduplicate, keeled, 3-veined, margins very narrowly hyaline. Stamen 6.

Species Description

Tufled annual. Culms to 75(-190)cm , erect , unbranch. Leaf blades acute 15-36.5(60) x 1-1.3(2.2)cm, glabrous; sheaths glabrous; ligule 8-12mm, acute, glabrous. Infl. 13-17.5cm, lowest branches single or paired, the longest 6-10cm, secondary branches short, appressed, pedicles 1.5-4mm, hairy. Spikelets 7.5-8.5(to tip of palea) x 3-3.2mm, persistent. Sterile lemmas equal, 2-2.4 x 0.8mm, triangular, acute, weakly keeled, glabrous, margins whitish-green. Fertile lemma 7-8.2mm, each side 2-2.2mm wide, oblong, abruptly acuminate, surface finely reticutately pitted, sparsely hispid on sides above, keel shortly ciliate near apex. palea 6.7-8mm. abruptly acuminate, each side 1.2-1.4mm wide, narrowly oblong, keel and sides shortly hispid above. Anthers c.1.8m.

Habit

Annual herb