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DICHANTHIUM Willem. Bluestem
Plant hermaphroditic, caespitose or rhizomatous or stoloniferous, perennial. Culms erect or ascending or decumbent; internodes
solid, glabrous, terete; nodes glabrous or bearded (some glabrate with age). Leaves basal and cauline; not distinctly
distichous; sheaths terete, margins open; auricles absent; ligules membranous or a ciliate membrane; blades flat, linear, lax,
apex acuminate. Panicles of a few to several racemose branches, open, terminal, sheaths subtending the inflorescence not
inflated and spathe-like; primary branches unbranched, digitate or subdigitate (rarely paired), spreading; aromatic or not
aromatic; branches glabrous or hairy; pedicels without a longitudinal groove, hairy or glabrous, terete or flattened.
Spikelets paired (ternate at branch apex) at each inflorescence node, similar in size and shape, disarticulation below the
glumes, dorsiventrally compressed, sessile spikelets fertile, pedicellate, spikelets sterile. Pedicellate spikelets well
developed, staminate or sterile, awnless. Sessile spikelets perfect; first glumes 2-keeled, gland-like depressions or
pits not present, abaxial surface flat to convex, smooth, chartaceous, glabrous or hairy, awnless; second glumes length
equal to first glumes; lower florets staminate or neuter; lemmas hyaline; apex, entire, awnless; paleas absent;
upper florets perfect, lemmas hyaline and producing an apical awn; paleas present or absent, hyaline. Stamens 1 or 2
or 3; anthers olive or yellow. Caryopses broadly elliptical, dorsiventrally compressed. Base chromosome number x=10.
A genus of about 16 species. A small genus of pasture or range plants from Africa, Asia, and Australia.
Some of the taxa are weedy (D. annulatum) in open habitats.
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