American Grama

Bouteloua americana (L.) Scribn. Proc. Acad. Phila 1891:306. 1891.
Aristida americana L. Syst. Nat. ed. 10. 2: 879. 1759.
Aristida Antillarum Poir. in Lam. Encyc. Suppl. 1: 451. 1810. (Type from Antilles.)
Bouteloua litigiosa Lag. Gen. & Sp. Nov. 5. 1816. (Based on Aristida americana L.)
Chaetaria Antillarum Beauv.; R. & S.Syst. Veg. 2: 395. 1817. (Based on Aristida Antillarum Poir.)
Atheropogon Antillarum Spreng. Syst. 1: 294. 1825. (Based on Aristida Antillarum Poir.)
Aristida subhifiora Steud. Syn. Gram. 138. 1854. (Type from Guadeloupe. Duchaissing.)
Eutriana Antillarum Steud. Syn. Gram. 217. 1854. (Based on Chaetaria Antillarum Beauv.)
Bouteloua elatior Griseb. Fl. Brit. W. Ind. 537. 1864. (Type from Antigua, Wullschlagel 660.)
Atheropogon americanus Fourn. Mex. PI. Gram. 2: 139. 1886. (Based on Aristida americana L.)
Aristida adscensionis var. americana Kuntze, Rev. Gen. 3': 340. 1898. (Based on A. americana L.)
Perennial; culms rather slender, branching, decumbent, sometimes prostrate-spreading, 30-60 cm. long, glabrous; sheaths glabrous, mostly much shorter than the internodes; ligule very short, ciliate; blades flat, 5-20 cm. long (shorter in depauperate plants), 1-3 mm. wide, glabrous, the margins scabrous and papillose or papillose-pilose; spikes 4-10, 1-4 cm. long, linear, ascending or spreading, falling entire; spikelets appressed, overlapping but not crowded; glumes acuminate, similar, the first 3-4 mm. long, the second slightly broader, 4-5 mm. long, glabrous; fertile floret 4—5 mm. long, acuminate, glabrous, the callus densely hairy on the sides, the central awn terminal, 2-3 mm. long, the lateral ones about 1.5 mm. long, 1 mm. from the tip; palea acuminate, exceeding the lemma; rudiment reduced to 3 scabrous awns 8-10 mm. long, the middle one stouter.
Type locality: Jamaica.
Distribution: Dry rocky hills, open ground, and waste places. West Indies, and southward to Brazil.

Perennials, Terrestrial, not aquatic, Stems trailing, spreading or prostrate, Stems nodes swollen or brittle, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems solitary, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem nodes bearded or hairy, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves mostly cauline, Leaves co nspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blade margins folded, involute, or conduplicate, Leaf blades mostly glabrous, Ligule present, Ligule a fringe of hairs, Inflorescence terminal, Inflorescence with 2 or more spikes, fascicles, glomerules, heads, or clusters per culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence with 2-10 branches, Inflorescence branches more than 10 to numerous, Inflorescence branches terminating in bristle or point, Rachis angular, Flowers bisexual, Spikelets sessile or subsessile, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Inflorescence branches deciduous, falling intact, Spikelets secund, in rows on one side of rachis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glume surface hairy, villous or pilose, Glumes 1 nerved, Lemma coriaceous, firmer or thicker in texture than the glumes, Lemma 3 nerved, Lemma glabrous, Lemma apex dentate, 2-fid, Lemma distinctly awned, more than 2-3 mm, Lemma with 3 awns, Lemma awn less than 1 cm long, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea shorter than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.