Leersia hexandra

Sw.
Endemic
Treatment appears in FNA Volume 24. Treatment on page 44.

Plants perennial; rhizomatous, rhizomes elongate, not scaly. Culms 25-150 cm tall, 1-1.5 mm thick, decumbent, rooting at the nodes, terminal portions erect, often floating, branched or unbranched; nodes pubescent, adjacent portions of the internodes glabrous or coarsely scabrous. Sheaths glabrous or coarsely scabrous, margins often ciliate; ligules 1-3 mm; blades 5-25 cm long, 3-15 mm wide, ascending, glabrous or pubescent. Panicles 5-15 cm, exserted at maturity, with 1 (2) branches per node; branches 3-10 cm, appressed to ascending, spikelet-bearing to near the base, spikelets appressed to slightly divergent, slightly imbricate. Spikelets 3.2-4.7 (5) mm long, 0.5-2 mm wide, ovate to elliptic. Lemmas ciliate on the keels and margins, short hispid or glabrous elsewhere, apices acute to acuminate; paleas ciliate on the keels; anthers 6, 2-3.2 mm. Caryopses about 2 mm, usually not developed. 2n = 48.

Distribution

Puerto Rico, Md., Miss., Tex., La., Ala., N.C., S.C., Tenn., Va., Ark., Ga., Fla.

Discussion

Leersia hexandra is found in wet areas, usually in fresh water along streams and ponds, where it sometimes forms floating mats. It grows in the southeastern United States and throughout much of the neotropics; the California record probably represents a recent introduction.

Leersia hexandra is sometimes a weed in rice. It usually flowers in late fall, but may flower throughout the year. Very little seed is set.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Leersia hexandra"
0.2 cm2 mm <br />0.002 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
acute +  and acuminate +
Grant L. Pyrah +
1 (?) +  and 3 (?) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
5 cm50 mm <br />0.05 m <br /> (25 cm250 mm <br />0.25 m <br />) +
not evident +
pubescent +  and glabrous +
linear +  and broadly lanceolate flat or folded +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
appressed;ascending +
spikelike +
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
not stipelike +
25 cm250 mm <br />0.25 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
decumbent +  and erect +
20 cm200 mm <br />0.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Puerto Rico +, Md. +, Miss. +, Tex. +, La. +, Ala. +, N.C. +, S.C. +, Tenn. +, Va. +, Ark. +, Ga. +  and Fla. +
capillary +
sometimes longer +
sterile +, fertile +, sexual +, unisexual +  and bisexual +
linear +  and suborbicular +
cylindrical +, oblong +  and ovoid +
subtending +
reduced +
uncinate +
solid +  and hollow +
aerenchymatous +
distributed +
glabrous +, hispid +  and short +
mucronate +, acute +  and acuminate +
subequal +
chartaceous +  and coriaceous +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranous +
annular +
inconspicuous +
fleshy +  and membranous +
complex +  and simple +
concealed +  and prominent +
2 +  and 1 +
well-developed +
glabrous +  and ciliate-hispid +
1-keeled +
subequal +
chartaceous +  and coriaceous +
5 cm50 mm <br />0.05 m <br /> (15 cm150 mm <br />0.15 m <br />) +
dry +  and fleshy +
scabrous +  and glabrous +
not prolonged +
scabrous +  and glabrous +
imbricate +  and divergent +
0.32 cm3.2 mm <br />0.0032 m <br /> (0.47 cm4.7 mm <br />0.0047 m <br />) +
[9/10] +, /2 +  and 1 +
ovate +  and elliptic +
0.5mm +  and 2mm +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
triangular +  and dome--shaped +
Gramineae +
Leersia hexandra +
species +
membranous +
aquatic +  and terrestrial +