Glyceria acutiflora

Torr.
Common names: Creeping mannagrass
Endemic
Treatment appears in FNA Volume 24. Treatment on page 83.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Plants perennial. Culms 30-100 cm tall, 3-6 mm thick, spongy, usually decumbent and rooting at the lower nodes. Sheaths smooth, weakly keeled; ligules 5-9 mm; blades 10-15 cm long, 3-8 mm wide, abaxial surfaces smooth, adaxial surfaces of the midcauline leaves often papillose. Inflorescences often racemes, sometimes panicles, 15-35 cm long, 1-2 cm wide, open at anthesis, bases often enclosed in the flag leaf-sheaths at maturity; branches 5.5-8 cm (absent in racemose plants), solitary or in pairs, appressed, most branches with 1-3 spikelets, the lower branches sometimes with more than 3; pedicels 1.5-2.5 mm. Spikelets 20-45 mm long, 2.5-3 mm wide, cylindrical and terete except slightly laterally compressed at anthesis, rectangular in side view, with 5-12 florets. Glumes unequal, acute; lower glumes 1.3-4.5 mm; upper glumes 3-7 mm; rachilla internodes 2-3 mm; lemmas 6-8.5 mm, scabridulous, 7-veined, gradually tapering from near midlength to the narrowly acute (less than 45°) or acuminate apices; paleas 0.7-3 mm longer than the lemmas, keels winged, tips parallel, intercostal region truncate, often splitting, apices appearing bifid, with 0.4-1 mm teeth; anthers 3, 1-2 mm. Caryopses about 3 mm. 2n = 40.

Distribution

Conn., N.J., N.Y., Del., W.Va., N.H., Tenn., Pa., Mass., R.I., Vt., Va., Ala., Ga., Ind., Maine, Md., Ohio, Mo., Mich., Ky.

Discussion

Glyceria acutiflora grows in wet soils and shallow water of the northeastern United States, extending from Michigan and Missouri to the Atlantic coast between southwestern Maine and Delaware. Its long paleas make G. acutiflora the most distinctive North American species of sect. Glyceria.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Glyceria acutiflora"
membranous +  and scarious +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
acuminate +  and acute +
Mary E. Barkworth +  and Laurel K. Anderton +
1 (?) +  and 3 (?) +
basal +  and apical +
keeled +  and rounded +
pseudopetiolate +  and branching +
persistent +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
10 cm100 mm <br />0.1 m <br /> (15 cm150 mm <br />0.15 m <br />) +
folded +  and flat +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
usually appressed;ascending +
5.5 cm55 mm <br />0.055 m <br /> (8 cm80 mm <br />0.08 m <br />) +
0 cm0 mm <br />0 m <br /> (20 cm200 mm <br />0.2 m <br />) +
Creeping mannagrass +
30 cm300 mm <br />0.3 m <br /> (100 cm1,000 mm <br />1 m <br />) +
decumbent +  and erect +
20 cm200 mm <br />0.2 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Conn. +, N.J. +, N.Y. +, Del. +, W.Va. +, N.H. +, Tenn. +, Pa. +, Mass. +, R.I. +, Vt. +, Va. +, Ala. +, Ga. +, Ind. +, Maine +, Md. +, Ohio +, Mo. +, Mich. +  and Ky. +
0 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
sometimes longer +
5 +  and 12 +
rectangular +
reduced +
shorter than to longer than the adjacent lemmas +
subtending +
unequal +
scarious +  and membranous +
5-11-veined +
uncinate +
15 cm150 mm <br />0.15 m <br /> (?) +  and 35 cm350 mm <br />0.35 m <br /> (?) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
hairy +, glabrous +, scabrous +  and smooth +
scabridulous +
tapering +
0.6 cm6 mm <br />0.006 m <br /> (0.85 cm8.5 mm <br />0.0085 m <br />) +
membranous +  and thinly coriaceous +
lacerate +
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
inconspicuous +
lanceolate +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
concealed +  and prominent +
2 +  and 1 +
well-developed +
reduced +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
dry +  and fleshy +
2 cm20 mm <br />0.02 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
compressed +, terete +  and cylindrical +
0.25 cm2.5 mm <br />0.0025 m <br /> (6 cm60 mm <br />0.06 m <br />) +
2.5mm +  and 3mm +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Glyceria acutiflora +
Glyceria sect. Glyceria +
species +
notched +, rounded +  and truncate +
membranous +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
prominent +  and evident +
aquatic +  and terrestrial +