Bouteloua rigidiseta

(Steud.) Hitchc.
Common names: Texas grama
Treatment appears in FNA Volume 25. Treatment on page 259.

Plants perennial; cespitose, without rhizomes or stolons, forming dense, small clumps. Culms 10-50 cm, erect, unbranched. Sheaths smooth, striate; ligules 0.2-0.3 mm, membranous, ciliate; blades 4-12 (17) cm long, 1-2 mm wide, abaxial surfaces sparsely short-pubescent, bases with papillose-based hairs on the margins, similar hairs also present on both surfaces. Panicles 3-6 cm, with 6-8 branches; branches 8-16 mm, hairy, becoming more sparsely so distally, with 2-6 spikelets, axes terminating beyond the base of the terminal spikelets, apices deeply bi or trifurcate; disarticulation at the base of the branches. Spikelets appressed, all alike, with 1 bisexual and 1-2 rudimentary florets. Glumes lanceolate, veins pubescent, apices acuminate; lower glumes 3-4 mm; upper glumes about 6 mm, pubescent over the veins, hairs about 0.7 mm, apices bilobed, awned from the sinuses; lowest lemmas 2.5-4 mm, glabrous or sparsely pubescent on the veins, 3-awned, awns wide basally, forming 3 triangular lobes, central awns flanked by 2 membranous 0.5-1.5 mm lobes; lowest paleas 4-5 mm, bilobed, veins often excurrent; second lemmas glabrous, 3-awned, awns 5-10 mm; second paleas 2-lobed, unawned; third lemmas similar to the second lemmas but smaller and without paleas. Caryopses (2) 3.5-3.7 mm. 2n = 40.

Distribution

Okla., Ark., Mass., Tex., La.

Discussion

Bouteloua rigidiseta grows in grassy pastures and openings in woods, usually in clay or sandy clay soils, from near sea level to approximately 700 m. It is both widespread and abundant within its range, which extends from the southern United States to northern Mexico, but has little value as a forage grass. It is one of the earliest flowering warm season grasses. Although similar to B. eludens, B. rigidiseta differs in its geographic distribution and glume pubescence, so the two taxa are unlikely to be confused in the field.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Bouteloua rigidiseta"
1 +  and 3 +
awned +  and bilobed +
J.K. Wipff +
(Steud.) Hitchc. +
1 (?) +  and 3 (?) +
well-developed +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
not fused +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
not pseudopetiolate +
4 cm40 mm <br />0.04 m <br /> (12 cm120 mm <br />0.12 m <br />) +
pubescent +  and glabrous +
usually linear +  and lanceolate occasionally ovate +
1mm;2mm +
subdigitate +  and digitate +
75 cm750 mm <br />0.75 m <br /> (?) +
spikelike +
not woody +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.37 cm3.7 mm <br />0.0037 m <br />) +
triangular +  and dome--shaped +
sometimes longer +
membranous +
Texas grama +
10 cm100 mm <br />0.1 m <br /> (50 cm500 mm <br />0.5 m <br />) +
not woody +
Okla. +, Ark. +, Mass. +, Tex. +  and La. +
not waisted +
capillary +
pistillate +  and staminate +
4-lobed +  and trilobed +
sometimes longer +
rudimentary +
1 +  and 2 +
round +  and compressed +
reduced +
shorter or longer +
subtending +
both +  and 1 +
lanceolate +
subequal +  and unequal +
papillose-based +
uncinate +
0.7 cm7 mm <br />0.007 m <br /> (?) +
paniculate +  and racemose +
hollow +  and solid +
not absent +
5-veined +, 7-13-veined +  and 1-3-veined +
smaller +
sometimes longer +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
membranous +
2 (?) +  and 3 (?) +
triangular +
membranous +
inconspicuous +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
pubescent +  and glabrous +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
concealed +  and prominent +
2 +  and 1 +
2-lobed +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
dry +  and fleshy +
spikelike +
elongate +
flabellate +
sessile +  and subsessile +
terete +, compressed +  and pectinate +
1 (?) +  and 3 (?) +
compound +  and simple +
2 (?) +  and 3 (?) +
Gramineae +
Bouteloua rigidiseta +
Bouteloua subg. Bouteloua +
species +
membranous +
6 cm60 mm <br />0.06 m <br /> (?) +
7 +  and 13 +
extended +
rhizomatous +  and stoloniferous +
plant +  and cespitose +
aquatic +  and terrestrial +