Plants annual or perennial; sometimes rhizomatous. Culms 1.5-150 cm, erect. Cauline leaves 1-3; sheaths open to the base; auricles absent; ligules truncate, entire, erose, or ciliolate; blades flat. Inflorescences terminal panicles, panicles condensed, often spikelike, linear to almost globose, more or less unilateral. Spikelets subsessile to shortly pedicellate, laterally compressed, dimorphic, usually paired, distal spikelet on each branch sometimes solitary, proximal spikelet of each pair sterile, almost completely concealing the fertile spikelet; disarticulation above the glumes and beneath the florets. Sterile spikelets persistent; florets 6-18, reduced to narrow, linear-lanceolate lemmas, sometimes awned, awns terminal; glumes narrow, linear. Fertile spikelets adaxial to the sterile spikelets; florets 1-5; rachillas glabrous, extending beyond the distal floret; glumes 2, subequal and shorter than the spikelets, thin, lanceolate, 1-veined, acute, sometimes awned; calluses short, blunt, glabrous; lemmas glabrous or pubescent, 5-veined, acute or bidentate, unawned to conspicuously awned; paleas about as long as the lemmas, bifid; lodicules 2, free, glabrous, ovate, bilobed; anthers 3; ovaries broadly ellipsoid, glabrous; styles separate. Caryopses oblong-ellipsoid, subterete, slightly dorsally compressed, sometimes adherent to the paleas; hila 1/5-1/2 as long as the grain, oblong to linear. x = 7. Name from the Greek, kynos, dog, and oura, tail, referring to the shape of the panicle.
Spikelets dimorphic, the sterile and fertile paired; sterile spikelets consisting of 2 glumes and several narrow, scabrous, acuminate lemmas on a continuous rachilla, borne in front of the fertile spikelets and nearly covering them; fertile spikelets 2-4-fld, the rachilla disarticulating; glumes narrow, unequal; lemmas broader, rounded on the back, scabrous, awn-tipped; lvs narrow; spikelets densely crowded in a spike-like or capitate panicle. 4, Europe and Medit. reg.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.