Bouteloua simplex

Lag.
Common names: Mat grama
Synonyms: Chondrosum prostratum Bouteloua procumbens
Treatment appears in FNA Volume 25. Treatment on page 265.

Plants annual. Culms 3-35 cm, usually decumbent, occasionally erect, rarely branching; internodes glabrous. Sheaths smooth, deeply striate; ligules 0.1-0.2 mm, of short hairs, sometimes with a few papillose-based hairs on either side; blades 2-8 cm long, 0.5-1.5 mm wide, flat to involute, adaxial surfaces mostly glabrous, often pilose basally. Panicles usually with only 1 branch (terminating the culm), or with 2-4 branches and subdigitate; branches 10-25 (40) mm, persistent, straight, arcuate, or circular, with 30-80 spikelets, axes terminating in a reduced spikelet; disarticulation above the glumes. Spikelets pectinate, with 1 bisexual floret and 1-2 rudimentary florets. Glumes glabrous, sometimes scabrous distally, acute or acuminate; lower glumes 1.5-2.5 mm; upper glumes 3.5-5 mm; lowest lemmas 2.5-3.5 mm, pilose over the veins, 3-awned, awns stout and flattened, central awns 1-2 mm, flanked by 2 membranous lobes, lateral awns shorter than the central awns; lowest paleas obovate, unawned; rachilla segments subtending second florets with densely pubescent apices; second florets reduced to an awn column with 3 awns of 5-6 mm; third florets, if present, flabellate scales. 2n = 20.

Distribution

Maine, Colo., N.Mex., Tex., Utah, Nebr., Kans., Ariz., Wyo.

Discussion

Bouteloua simplex grows on rocky, open slopes in grassy and open shrub vegetation at 1200-2500 m. Its native range extends from the southwestern United States through Mexico and Central America to western South America. It is adventive in Maine, where it has been grows in disturbed places, but it is not common there.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Bouteloua simplex"
pilose +  and glabrous +
1 +  and 3 +
J.K. Wipff +
1 (?) +  and 3 (?) +
well-developed +
flattened +
keeled +  and rounded +
pseudopetiolate +  and branching +
not fused +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
not pseudopetiolate +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
pubescent +  and glabrous +
flat +  and involute +
0.5mm;1.5mm +
subdigitate +  and digitate +
40 cm400 mm <br />0.4 m <br /> (?) +
persistent +
circular +  and arcuate +
not woody +
triangular +  and dome--shaped +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
sometimes longer +
membranous +
Mat grama +
3 cm30 mm <br />0.03 m <br /> (35 cm350 mm <br />0.35 m <br />) +
not woody +
Maine +, Colo. +, N.Mex. +, Tex. +, Utah +, Nebr. +, Kans. +, Ariz. +  and Wyo. +
not waisted +
capillary +
pistillate +  and staminate +
4-lobed +  and trilobed +
sometimes longer +
round +  and compressed +
reduced +
shorter or longer +
subtending +
both +  and 1 +
acuminate +  and acute +
subequal +  and unequal +
papillose-based +
uncinate +
paniculate +  and racemose +
hollow +  and solid +
not absent +
5-veined +, 7-13-veined +  and 1-3-veined +
sometimes longer +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
membranous +
membranous +
inconspicuous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
concealed +  and prominent +
2 +  and 1 +
dry +  and fleshy +
spikelike +
elongate +
flabellate +
sessile +  and subsessile +
30 +  and 80 +
pectinate +
1 (?) +  and 3 (?) +
compound +  and simple +
2 (?) +  and 3 (?) +
Chondrosum prostratum +  and Bouteloua procumbens +
Bouteloua simplex +
Bouteloua subg. Chondrosum +
species +
membranous +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
7 +  and 13 +
extended +
rhizomatous +  and stoloniferous +
aquatic +  and terrestrial +