Bouteloua aristidoides |
Bouteloua ramosa |
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needle grama |
Chino grama |
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Habit | Plants annual; tufted. | Plants perennial; densely cespitose, bases hard, knotty, without rhizomes or stolons. | ||||
Culms | 4-60 cm, outer culms of a tuft decumbent, sometimes geniculate, branched at the lower nodes. |
25-60 cm, numerous, somewhat woody at the base, geniculate, branching profusely from the lower nodes; nodes usually 4-5; lower internodes glabrous, without a conspicuous, white, chalky bloom. |
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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. |
1-3(5) cm, with 1-3(4) branches; branches 10-35 mm, persistent, ascending to widely divergent, becoming arcuate, dark, with 24-45(64) spikelets, branches terminating in a reduced, needlelike, 2-5 mm spikelet; disarticulation above the glumes. |
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Spikelets | appressed. |
with 1 bisexual floret and 1-2 rudimentary florets. |
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Glumes | acute to acuminate, glabrous or sparsely short-hairy, hairs not papillose-based; lower glumes 2-2.5 mm; upper glumes 2-3.5 mm; lowest lemmas 2.5-4 mm, sparsely to densely hairy, 3-awned, awns slightly shorter than the lemma bodies, central awns flanked by 2 membranous lobes; lowest paleas about 4.5 mm, mostly glabrous, sometimes puberulent distally, acute to acuminate, veins not excurrent, unawned; second florets about 4.5 mm, 3-awned, awns 3-5 mm; rachilla segments subtending second florets with densely pubescent apices; third florets, if present, flabellate scales, 1-awned. |
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Caryopses | 2.5-3 mm. |
1-1.2 mm long, about 0.4 mm wide. |
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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. |
0.1-0.2 mm, of hairs; blades 2-7 cm long, 1-2 mm wide, mostly flat but the tips involute. |
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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. |
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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. |
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2n | = 40. |
= 40. |
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Bouteloua aristidoides |
Bouteloua ramosa |
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Distribution |
AZ; CA; MD; NM; NV; TX; UT
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TX |
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Discussion | There are two varieties, both of which grow in the Flora region. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Bouteloua ratnosa is locally common on rocky limestone slopes and flats among shrubs and Agave lecheguilla. Its range extends from the Trans Pecos region of western Texas to adjacent northern Mexico, particularly the state of Coahuila. Reeder and Reeder (1980) provide an excellent discussion of B. ramosa and B. breviseta. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 25, p. 255. | FNA vol. 25, p. 267. | ||||
Parent taxa | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Bouteloua > subg. Bouteloua | Poaceae > subfam. Chloridoideae > tribe Cynodonteae > Bouteloua > subg. Chondrosum | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Name authority | (Kunth) Griseb. | Scribn. ex Vasey | ||||
Web links |