Caribbean Bristlegrass

Panicum utowanaeum Scribn. in Milisp. Field Columb. Mus
Publ. Bot. 2: 25. 1900.
Panicum Sintenisii Nash, Bull. Torrey Club 30: 382. 1903.
Plants tufted from the nodes of short, slender rootstocks, glabrous; culms ascending or somewhat spreading, 25-60 cm. high, slender, compressed, sparingly branching; leaf-sheaths
i
shorter than the internodes, compressed, especially the lowermost, ciliate at the auriculate summit; ligule a minute ring of stiff hairs; blades erect or spreading above, 10-20 cm. long, 1-4 mm. wide, slightly scabrous on the margin (sometimes sparsely pilose on the upper surface at the base), narrowed and more or less involute at the base and much narrower than the sheath; panicles 3-10 cm. long, very slender, the scattered, erect branches 1-3 cm. long, the bristle usually equaling or exceeding the spikelet; spikelets subsessile, 2-2.1 mm. long, 0.6-0.7 mm. wide, elliptic, somewhat beaked at the summit, glabrous, pale with green nerves; first glume half as long as the spikelet, acute, 3 -nerved; second glume two thirds to three fourths as long as the fruit, 3-5-nerved, the sterile lemma 5-nerved, abruptly pointed; fruit 1.9 mm. long, 0.6 mm. wide, elliptic, minutely rugose, slightly beaked at the acute apex.
Type locality: Guanica, Porto Rico.
Distribution: Cuba, Hispaniola, Porto Rico, and Guadeloupe; also in Venezuela.

Perennials, Terrestrial, not aquatic, Stolons or runners present, Stems nodes swollen or brittle, Stems erect or ascending, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes solid or spongy, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranke d, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf sheath enlarged, inflated or distended, Leaf blades linear, Leaf blades very narrow or filiform, less than 2 mm wide, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringe of hairs, Inflorescence terminal, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence branches more than 10 to numerous, Inflorescence branches terminating in bristle or point, Flowers bisexual, Spikelets sessile or subsessile, Spikelets dorsally compressed or terete, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets with 2 florets, Spikelet with 1 fertile floret and 1-2 sterile florets, Spikelets solitary at rach is nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating below the glumes, Spikelets all subtended by bristles, Spikelet bristles 1-3, Inner spikelet bristles all round, Spikelet bracts or bristles disarticulating with spikelet, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes 3 nerved, Glumes 4-7 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma becoming indurate, enclosing palea and caryopsis, Lemma 5-7 nerved, Lemma glabrous, Lemma rugose, with cross wrinkles, or roughened, Lemma apex acute or acuminate, Lemma awnless, Lemma margins inrolled, tightly covering palea and caryopsis, Lemma straight, Palea present, well developed, Palea shorter than lemma, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.