Willkommia texana

Hitchc
Common names: Willkommia
Treatment appears in FNA Volume 25. Treatment on page 228.

Plants perennial; cespitose or stoloniferous. Culms (12) 17-65 cm, glabrous; nodes 4-6 (7), glabrous. Leaves cauline; sheaths mostly glabrous, upper margins sometimes pubescent; ligules 0.3-0.6 mm, truncate; blades (1) 4-21 cm long, 0.6-3.5 mm wide, involute to flat, glabrous, margins pubescent. Panicles (6) 7-34 (44) cm long, 4-10 mm wide; branches 4-13 (20), 1-8 cm, appressed, each branch usually terminating in a reduced, sterile spikelet, lowest branches usually partially enclosed in the uppermost sheaths at maturity. Spikelets 3.5-5 mm; disarticulation usually below the glumes, sometimes the first-glume persistent. Lower glumes 2-3.5 mm, glabrous; upper glumes 3.3-4.8 mm, glabrous and smooth below, scabridulous above; lemmas 3.0-4.2 mm, usually appressed pilose between the veins, lateral-veins obscure, midveins sometimes excurrent; paleas 2.5-3.4 mm, pubescent between the veins; anthers 3, 0.3-0.9 (1.1) mm, yellow-orange. Caryopses 1.4-2 mm. 2n = 60.

Discussion

Willkommia texana grows on clay pans, alkaline flats, and sandy soils, in open or bare areas of Texas and (rarely) Oklahoma and, as a disjunct, in Argentina. The Oklahoma record may represent a recent introduction. North American plants belong to Willkommia texana Hitchc. var. texana. They differ from the Argentinean variety, W. texana var. stolonifera Parodi, in being cespi¬tose rather than stoloniferous.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Willkommia texana"
1.1 cm11 mm <br />0.011 m <br /> (?) +
yellow-orange +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
Mucronate (?) +, Rounded (?) +  and Acute (?) +
J.K. Wipff +
Hitchc +
1 (?) +  and 3 (?) +
multiple +, , +  and single +
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 /> (21 cm210 mm <br />0.21 m <br />) +
involute +  and flat +
0.6mm;3.5mm +
spikelike +
not woody +
acute +  and pointed +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
triangular +  and dome--shaped +
sometimes longer +
membranous +
Willkommia +
ascending +  and erect +
17 cm170 mm <br />0.17 m <br /> (65 cm650 mm <br />0.65 m <br />) +
not woody +
Okla. +  and Tex. +
not waisted +
capillary +
pistillate +  and staminate +
sometimes longer +
bisexual +  and fertile +
round +  and compressed +
reduced +
shorter or longer +
subtending +
uncinate +
paniculate +  and racemose +
hollow +  and solid +
not absent +
involute +  and flat +
0.3 cm3 mm <br />0.003 m <br /> (0.42 cm4.2 mm <br />0.0042 m <br />) +
membranous +
sometimes longer +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
membranous +
inconspicuous +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
concealed +  and prominent +
4 +  and 6 +
2 +  and 1 +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.34 cm3.4 mm <br />0.0034 m <br />) +
7cm +  and 34cm +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
dry +  and fleshy +
spikelike +
1 +  and 60 +
compressed +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
1 (?) +  and 3 (?) +
compound +  and simple +
2 (?) +  and 3 (?) +
Gramineae +
Willkommia texana +
Willkommia +
species +
membranous +
scabridulous +
0.33 cm3.3 mm <br />0.0033 m <br /> (0.48 cm4.8 mm <br />0.0048 m <br />) +
7 +  and 13 +
plant +  and cespitose +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +