Bouteloua aristidoides |
Bouteloua kayi |
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needle grama |
Kay's grama |
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Habit | Plants annual; tufted. | Plants perennial; cespitose, without rhizomes or stolons. | ||||
Culms | 4-60 cm, outer culms of a tuft decumbent, sometimes geniculate, branched at the lower nodes. |
10-50 cm, erect; nodes glabrous; internodes glabrous, scabridulous between the veins. |
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Leaves | mostly basal; sheaths scabridulous or glabrous, sparsely pubescent basally; ligules 0.3-0.5 mm, membranous, ciliate; blades to 20 cm long, 0.5-1.5 mm wide, involute, scabridulous adaxially. |
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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. |
8-11 cm, with 7-20 branches; branches 15-30 mm, persistent, with (6)14-20 pedicellate spikelets, axes terminating in a spikelet; pedicels 0.6-0.8 mm; disarticulation above the glumes. |
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Spikelets | appressed. |
6-8 mm, pectinate, with 1 bisexual and 1 rudimentary floret. |
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Glumes | subequal, 2.5-4 mm, glabrous, acute or bidentate, midvein sometimes excurrent as a mucro or short awn; lowest lemmas 5-7 mm, glabrous, 3-awned, awns 3-4 mm, central awns flanked by 2 membranous, acuminate, 0.4—0.6 mm lobes; lowest paleas sometimes reduced to 2 awns, awns 1-2 mm, anthers 1.2-1.3 mm, yellow; second florets glabrous, reduced to 1-3 awns, awns 3-4 mm. |
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Caryopses | 2.5-3 mm. |
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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. |
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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. |
= unknown. |
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Bouteloua aristidoides |
Bouteloua kayi |
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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 kayi is only known from the mountainous limestone terrain along the Rio Grande River in south-western Brewster County, Texas, at 2200-2500 m. Superficially, it resembles B. trifida. (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. 264. | ||||
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. | Warnock | ||||
Web links |