Trisetum cernuum

Trin.
Common names: Nodding trisetum
Endemic
Synonyms: Trisetum nutkanense
Treatment appears in FNA Volume 24. Treatment on page 748.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants perennial, with both fertile and sterile shoots; cespitose, not rhizomatous. Culms (30) 50-110 cm, clumped, erect, glabrous or pubescent. Leaves 2-3 per culm; sheaths scabridulous or pilose; ligules 1.5-3 mm, truncate, erose to lacerate; blades (8.5) 15-20+ cm long, (3) 7-12 mm wide, flat, ascending, lax at maturity, often scabridulous. Panicles 10-30 cm long, (1) 2-9 cm wide, open, nodding, green or tan, occasionally purple-tinged; branches 2-12+ cm, most, except sometimes the uppermost, spikelet-bearing only towards the apices, with the basal (1/5) 1/3-1/2 bare, filiform, flexuous, at least the lowest 1-3 whorls spreading or drooping. Spikelets 6-12 mm, subsessile to pedicellate, pedicels to 2 cm, usually with 2-3 functional florets below 1-2 reduced florets; rachilla internodes and hairs 1-2.5 mm; disarticulation above the glumes, beneath the florets. Glumes unequal; lower glumes 0.75-2 (3) mm, subulate; upper glumes 3.5-5 mm long, shorter than the lowest florets, 2-3 times as wide as the lower glumes, widest at or above the middle, ovate or obovate, rounded to the acuminate apices; callus hairs to 1 mm; lemmas 5-6 mm, broadly lanceolate, glabrous, bifid, teeth to 1.3 mm, awned, awns (7) 9-14 mm, arising from above midlength to just below the teeth, exceeding the lemma apices, arcuate to flexuous; paleas shorter than the lemmas; anthers about 1 mm. Caryopses 2.5-3.2 mm, densely to sparsely pubescent. 2n = 42.

Discussion

Trisetum cernuum grows in moist woods, on stream banks, lake and pond shores, and floodplains of the western Flora region. The hairiness of the leaf sheaths varies, often within a plant.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Trisetum cernuum"
membranous +  and scarious +
1 cm10 mm <br />0.01 m <br /> (?) +
entire +, bifid +  and apiculate +
acuminate +
John H. Rumely +
1 (?) +  and 3 (?) +
7 cm70 mm <br />0.07 m <br /> (?) +
straight +
basal +  and terminal +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
15 cm150 mm <br />0.15 m <br /> (20 cm200 mm <br />0.2 m <br />) +
not evident +
scabridulous +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
filiform +
2 cm20 mm <br />0.02 m <br /> (12 cm120 mm <br />0.12 m <br />) +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Nodding trisetum +
extravaginal +  and basal +
pubescent +  and glabrous +
50 cm500 mm <br />0.5 m <br /> (110 cm1,100 mm <br />1.1 m <br />) +
not woody +
Conn. +, Mass. +, Maine +, N.H. +, Vt. +, Wash. +, Colo. +, N.J. +, Wis. +, Pacific Islands (Hawaii) +, Wyo. +, N.Mex. +, Tex. +, La. +, N.C. +, Alta. +, B.C. +, Greenland +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, Que. +, Sask. +, Yukon +, Tenn. +, N.Y. +, Pa. +, Okla. +, S.Dak. +, Calif. +, Nev. +, Va. +, Alaska +, Ariz. +, Idaho +, Utah +, Mo. +, Minn. +, Mich. +, R.I. +, Kans. +, Mont. +, Miss. +  and Oreg. +
0 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
1 +  and 2 +
sterile +  and bisexual +
compressed +
reduced +
shorter or longer +
subtending +
unequal +
uncinate +
diffuse +  and dense +
lanceolate +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
lacerate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranous +
inconspicuous +
usually slenderly lobed +  and fimbriate +
0.075 cm0.75 mm <br />7.5e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
concealed +  and prominent +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
2-keeled +
subequal +  and longer +
membranous +
purple-tinged +, tan +  and green +
10cm +  and 30cm +
spikelike +
2 cm20 mm <br />0.02 m <br /> (9 cm90 mm <br />0.09 m <br />) +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
dry +  and fleshy +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
scabridulous +
sterile +  and fertile +
subsessile +  and pedicellate +
1 +  and 60 +
compressed +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Trisetum nutkanense +
Trisetum cernuum +
Trisetum +
species +
bristlelike +
membranous +
0 cm0 mm <br />0 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
rounded +, obovate +  and ovate +
above the middle +, widest +  and 2-3 times as wide as the lower glumes +
parallel +  and converging +
plant +  and cespitose +
aquatic +  and terrestrial +