Oryza longistaminata

A. Chev. & Roehr.
Common names: Longstamen rice
Treatment appears in FNA Volume 24. Treatment on page 38.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants perennial; extensively rhizomatous. Culms to 2+ m tall, to 25+ mm thick at the base, soft and spongy, erect or decumbent, sometimes floating, rooting at the lower nodes. Sheaths shorter or nearly as long as the internodes, smooth, glabrous; auricles to 15 mm; ligules 15-45 mm, acute, often splitting; blades to 45 cm long, 10-50 mm wide, linear-lanceolate to narrowly elliptic, glabrous, smooth or scabrous abaxially, scabrous adaxially, acute or 2-cleft. Panicles (16) 20-30 (40) cm long, 2.5-8 cm wide, exserted; branches 7.5-15 cm, ascending; pedicels 0.5-4 (7) mm. Spikelets 7-9 mm long, 2-3 mm wide, narrowly oblong, deciduous, obliquely articulated with the pedicel, disarticulation scar lateral. Sterile florets 2-4 mm, 1/5 – 3/5 as long as the spikelets, sometimes trilobed, lateral lobes shorter than the central lobe. Functional florets: lemmas 7-9 mm long, 1.8-2.5 mm wide, narrowly elliptic, scabrous to hispid over the veins, awned, lemma-awn junctions glabrous, colored as the lemmas, awns (2.6) 3.5-8 cm; paleas usually slightly shorter than the lemmas, narrower, acute or tapering; anthers 5-7 mm. Caryopses 7.5-8.5 mm, oblong, light-brown, glossy. Haplome A. 2n = 24.

Discussion

Oryza longistaminata is native to Africa; it has not yet been found in North America. It is included here because its establishment in North America would seriously impact North American agriculture. The U.S. Department of Agriculture considers it a noxious weed; plants found growing within the United States should be promptly reported to that agency.

In its native range, Oryza longistaminata grows in swampy areas, pond and lake edges, irrigation canals, and streams and rivers in areas that are permanently wet or seasonally dry.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Oryza longistaminata"
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
unawned +  and awned +
acute +  and acuminate +
0 cm0 mm <br />0 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Mary E. Barkworth +  and Edward E. Terrell +
A. Chev. & Roehr. +
1 (?) +  and 3 (?) +
2.6 cm26 mm <br />0.026 m <br /> (?) +
3.5 cm35 mm <br />0.035 m <br /> (8 cm80 mm <br />0.08 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
not +  and fused +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
0 cm0 mm <br />0 m <br /> (45 cm450 mm <br />0.45 m <br />) +
not evident +
2-cleft +, acute +, linear-lanceolate +  and narrowly elliptic +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
spikelike +
7.5 cm75 mm <br />0.075 m <br /> (15 cm150 mm <br />0.15 m <br />) +
stipelike +, flat +  and rounded +
Longstamen rice +
0 cm0 mm <br />0 m <br /> (200 cm2,000 mm <br />2 m <br />) +
0 cm0 mm <br />0 m <br /> (330 cm3,300 mm <br />3.3 m <br />) +
0 cm0 mm <br />0 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Va. +, Puerto Rico +, Virgin Islands +, Okla. +, Miss. +, Tex. +, La. +, Calif. +, N.C. +, Ala. +, Tenn. +, Ark. +, Ill. +, Ga. +, S.C. +, Fla. +  and Mo. +
capillary +
sometimes longer +
1/5 +  and 3/5 +
acute +  and acuminate +
cylindrical +, oblong +  and ovoid +
subtending +
reduced +
uncinate +
solid +  and hollow +
aerenchymatous +
basal +  and cauline +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
scabrous +  and hispid +
indurate +  and coriaceous +
1.8mm +  and 2.5mm +
1.5 cm15 mm <br />0.015 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
membranous +
annular +
inconspicuous +
fleshy +  and membranous +
scabridulous +  and smooth +
complex +  and simple +
concealed +  and prominent +
2 +  and 1 +
well-developed +
usually slightly shorter +
tapering +  and acute +
narrower +
20cm +  and 30cm +
2.5 cm25 mm <br />0.025 m <br /> (8 cm80 mm <br />0.08 m <br />) +
7 cm70 mm <br />0.07 m <br /> (?) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
dry +  and fleshy +
not prolonged +
nearly +  and shorter +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
[9/10] +, /2 +  and 1 +
2mm +  and 3mm +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
triangular +  and dome--shaped +
Gramineae +
Oryza longistaminata +
species +
membranous +
not inflated +
terrestrial +  and aquatic +