needle grama, more...
[Aristida unilateralis Willd. ex Steud., more]
Plants annual; tufted. Culms 4-60 cm, outer culms of a tuft decumbent,
sometimes geniculate, branched at the lower nodes. Ligules 0.2-0.5 mm,
membranous, lacerate or ciliate; blades 2-5(9) cm long, 0.7-2 mm wide,
flat or folded, adaxial surfaces sometimes with papillose-based hairs, margins
usually with papillose-based hairs near the ligules. Panicles 2.5-10.5
cm, with (1)4-15 branches; branches 5-45 mm, deciduous, densely pubescent
(at least basally), with 2-10 spikelets per branch, axes extending 2-10 mm beyond
the base of the terminal spikelets, apices entire; disarticulation at
the base of the branches, the break forming a sharp tip. Spikelets appressed.
Proximal spikelet on each branch with 1 floret; lower glumes 1.5-3.5
mm, glabrous, narrow to subulate; upper glumes 5.5-6.2 mm, densely pubescent,
at least on the basal 1/2; lemmas 5.8-6 mm, acuminate, unawned; lowest
paleas almost as long as the lemmas, bifid, glabrous; rachillas prolonged
beyond the florets for about 0.5 mm. Distal spikelets with 1 bisexual
and 1 rudimentary floret;glumes unequal, glabrous, minutely scabrous
on the keels; narrowly acute or acuminate; lower glumes 1.5-2 mm; upper
glumes 5-6 mm, glabrous or sparsely pubescent basally, often divergent;
lowest lemmas 6-8 mm, veins pubescent, lateral veins excurrent as short
(to 1 mm) awns, acuminate, midvein extended into a setaceous tip or a short
awn; lowest paleas 5-7 mm, bifid, veins often excurrent as short awns;
anthers about 2.5 mm, yellow or yellow and red; distal florets
reduced to a pubescent, 3-awned, awn column, awns 2-7 mm, exserted. Caryopses
2.5-3 mm. 2n = 40.
There are two varieties, both of which grow in the Flora region.
Plant: Annual grass to 50 cm; blades 2-5 cm long, <2mm wide, flat or folded; panicles 3-10 cm with 4-15 branches; branches one-sided, 10-45 mm, delicate, deciduous, densely pubescent with 2-10 spikelets/branch. References: Delta World Grasses
Dr. David Bogler, USDA NRCS PLANTS Database
Annuals, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tuft ed, or clustered, Stems terete, round in cross section, or polygonal, Stems branching above base or distally at nodes, 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 conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath hairy at summit, throat, or collar, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blade margins folded, involute, or conduplicate, Leaf blades mostly glabrous, Leaf blades more or less hairy, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringed, ciliate, or lobed membrane, 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 w ith 2-10 branches, Inflorescence branches more than 10 to numerous, Inflorescence branches 1-sided, 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 distinctly unequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glumes 1 nerved, Lemma coriaceous, firmer or thicker in texture than the glumes, Lemma 3 nerved, Lemma glabrous, Lemma body or surface hairy, Lemma apex acute or acuminate, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea shorter than lemma, Palea 2 nerved or 2 keeled, Stamen s 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.