Leersia oryzoides

(L.) Sw.
Common names: Rice cutgrass Leersie faux-riz
Treatment appears in FNA Volume 24. Treatment on page 44.

Plants perennial; rhizomatous, rhizomes elongate, scaly, scales not imbricate. Culms 35-150 cm tall, 1-3 mm thick, branching, decumbent, sprawling, rooting at the nodes, terminal portions erect. Sheaths scabrous; ligules 0.5-1 mm; blades 7-30 cm long, 5-15 mm wide, spreading to slightly ascending, both surfaces usually scabrous. Panicles 10-30 cm, terminal, also axillary, exserted or enclosed at maturity, spreading on exserted panicles, usually 2 or more branches at the lowest nodes, 1 at the upper nodes; branches 4-10 cm, the lower 1/3 naked, spikelets imbricate. Spikelets (4) 4.2-6.5 mm long, 1.3-1.7 mm wide, elliptic. Lemmas and paleas usually ciliate on the keels and margins, glabrous or puberulent elsewhere; anthers 3, 1.5-2 (3) mm in chasmogamous spikelets, 0.4-0.7 mm in cleistogamous spikelets. Caryopses 2-3.5 mm, asymmetrically pyriform to obovoid, whitish to dark-brown. 2n = 48.

Distribution

Conn., N.J., N.Y., Wash., Del., D.C., Wis., W.Va., Md., Fla., Wyo., N.H., N.Mex., Tex., La., Tenn., N.C., S.C., Pa., Nev., Mass., Maine, R.I., Vt., Va., Colo., Calif., Ala., Kans., N.Dak., Nebr., Okla., S.Dak., Ark., Ill., Ga., Ind., Iowa, Ariz., Idaho, Ohio, Utah, Mo., Minn., Mich., Mont., Miss., Ky., Oreg., B.C., Man., N.B., N.S., Ont., P.E.I., Que., Sask.

Discussion

Leersia oryzoides grows in wet, heavy, clay or sandy soils, and is often aquatic. It is found across most of southern Canada, extending south throughout the contiguous United States into northern Mexico, and flowers from July to October. It has also become established in Europe and Asia.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Leersia oryzoides"
3 cm30 mm <br />0.03 m <br /> (?) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
Grant L. Pyrah +
(L.) Sw. +
1 (?) +  and 3 (?) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
7 cm70 mm <br />0.07 m <br /> (30 cm300 mm <br />0.3 m <br />) +
not evident +
linear +  and broadly lanceolate flat or folded +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
spikelike +
4 cm40 mm <br />0.04 m <br /> (10 cm100 mm <br />0.1 m <br />) +
not stipelike +
Rice cutgrass +  and Leersie faux-riz +
rooting +  and branching +
sprawling +  and decumbent +
35 cm350 mm <br />0.35 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 /> (0.3 cm3 mm <br />0.003 m <br />) +
Conn. +, N.J. +, N.Y. +, Wash. +, Del. +, D.C. +, Wis. +, W.Va. +, Md. +, Fla. +, Wyo. +, N.H. +, N.Mex. +, Tex. +, La. +, Tenn. +, N.C. +, S.C. +, Pa. +, Nev. +, Mass. +, Maine +, R.I. +, Vt. +, Va. +, Colo. +, Calif. +, Ala. +, Kans. +, N.Dak. +, Nebr. +, Okla. +, S.Dak. +, Ark. +, Ill. +, Ga. +, Ind. +, Iowa +, Ariz. +, Idaho +, Ohio +, Utah +, Mo. +, Minn. +, Mich. +, Mont. +, Miss. +, Ky. +, Oreg. +, B.C. +, Man. +, N.B. +, N.S. +, Ont. +, P.E.I. +, Que. +  and Sask. +
capillary +
sometimes longer +
sterile +, fertile +, sexual +, unisexual +  and bisexual +
linear +  and suborbicular +
cylindrical +, oblong +  and ovoid +
subtending +
reduced +
uncinate +
solid +  and hollow +
aerenchymatous +
distributed +
puberulent +  and glabrous +
mucronate +, acute +  and acuminate +
subequal +
chartaceous +  and coriaceous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
membranous +
annular +
inconspicuous +
fleshy +  and membranous +
complex +  and simple +
concealed +  and prominent +
2 +  and 1 +
well-developed +
puberulent +  and glabrous +
1-keeled +
subequal +
chartaceous +  and coriaceous +
enclosed +, exserted +  and axillary +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
dry +  and fleshy +
not prolonged +
not imbricate +
0.42 cm4.2 mm <br />0.0042 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
[9/10] +, /2 +  and 1 +
cleistogamous +  and chasmogamous +
terete +  and compressed +
1.3mm +  and 1.7mm +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
triangular +  and dome--shaped +
Gramineae +
Leersia oryzoides +
species +
membranous +
aquatic +  and terrestrial +