Lolium rigidum

Gaudin
Common names: Stiff ryegrass
Synonyms: Lolium strictum
Treatment appears in FNA Volume 24. Treatment on page 456.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants annual. Culms to 70 cm. Blades to 17 cm long, 0.5-5 (8) mm wide. Spikes 3-30 cm, with 2-20 spikelets; rachises 0.5-3.5 mm thick at the nodes, with the spikelets somewhat sunken in the rachises and partly concealed by the glumes. Spikelets 5-18 mm long, 1-3 (7) mm wide, with 2-8 (11) florets. Glumes 4-20 (30) mm, usually from 3/4 as long as to slightly exceeding the distal florets, rather indurate; lemmas 3-8.5 (10.5) mm long, 0.9-2 mm wide; paleas slightly shorter than to slightly longer than the lemmas, usually unawned, sometimes awned, awns to 10 mm; anthers 1.2-3.2 mm. Caryopses 2.7-5.5 mm long, 1-1.5 mm wide, 3 or more times longer than wide. 2n = 14.

Distribution

Tex., Man., Calif., La., Oreg., Miss., Ariz., Mo.

Discussion

Lolium rigidum is native to Europe, North Africa, and western Asia. It has been found as a weed of roadsides and waste places at scattered locations in the contiguous United States and Canada.

Lolium rigidum intergrades with L. perenne, L. multiflorum, and, occasionally, L. temulentum. Hybrids with L. multiflorum are called Lolium xhubbardii Jansen & Wacht. ex B.K. Simon.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Lolium rigidum"
membranous +  and scarious +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
Edward E. Terrell +
Gaudin +
1 (?) +  and 3 (?) +
straight +
subterminal +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
0 cm0 mm <br />0 m <br /> (17 cm170 mm <br />0.17 m <br />) +
not evident +
cross +, linear +  and narrowly lanceolate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
spikelike +
Stiff ryegrass +
not branching +
erect to decumbent +
slender +  and stout +
0 cm0 mm <br />0 m <br /> (70 cm700 mm <br />0.7 m <br />) +
not woody +
Tex. +, Man. +, Calif. +, La. +, Oreg. +, Miss. +, Ariz. +  and Mo. +
1/5 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 8 +
sterile +  and bisexual +
compressed +
reduced +
shorter or longer +
subtending +
rounded +, lanceolate +  and oblong +
unequal +
0.4 cm4 mm <br />0.004 m <br /> (2 cm20 mm <br />0.02 m <br />) +
uncinate +
0.3 cm3 mm <br />0.003 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
rounded +, oblong +, ovate +  and lanceolate +
membranous +
0.9mm +  and 2mm +
0 cm0 mm <br />0 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
membranous +
inconspicuous +
lanceolate +  and ovate +
concealed +  and prominent +
2 +  and 1 +
well-developed +
slightly shorter than to slightly longer than the lemmas +
2-keeled +
membranous +
spikelike +
dry +  and fleshy +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
3 cm30 mm <br />0.03 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
2 +  and 20 +
compressed +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1mm +  and 3mm +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Lolium strictum +
Lolium rigidum +
species +
membranous +
parallel +  and converging +
aquatic +  and terrestrial +