Poa pratensis subsp. angustifolia

(L.) Lej.
Synonyms: Poa angustifolia
Treatment appears in FNA Volume 24. Treatment on page 526.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants moderately densely to densely tufted. Basal branching intra and extravaginal, intravaginal shoots clustered. Culms 25-80 cm. Innovation shoot blades 10-45 cm long, 0.4-1 mm wide, all involute, sometimes narrower than the cauline blades, adaxial surfaces sparsely pubescent; cauline blades involute or folded, somewhat firm, adaxial surfaces sparsely pubescent. Panicles 8-18 cm, narrowly pyramidal or loosely contracted, branches ascending to spreading, smooth or sparsely to densely scabrous, with several to many spikelets per branch. Spikelets narrowly lanceolate, not bulbiferous; florets normal. Glume keels strongly compressed, sparsely to moderately scabrous; upper glumes shorter than to nearly equaling the lowest lemmas; lemmas 2.5-3.5 mm, finely muriculate, lateral-veins glabrous; palea keels scabrous, glabrous, intercostal regions glabrous. 2n = 28, 46, 48-54, 56, 57, 59, 60, 61, 62, 63, 64, 65, 66, 68, 70, 72, 83.

Discussion

Poa pratensis subsp. angustifolia is a western Eurasian subspecies that is known from scattered locations throughout the temperate North American distribution of the species. It is characterized by the predominance of fascicles of elongate, narrow, involute blades on the intravaginal vegetative shoots, and slender panicles with small spikelets. Recent research has shown that it is primarily a low polyploid.

Selected References

None.

Lower Taxa

None.

"thin" is not a number."decumbent" is not a number.

83 +, 72 +, 70 +, 68 +, 66 +, 65 +, 64 +, 63 +, 62 +, 61 +, 60 +, 59 +, 57 +, 56 +, 48 +  and 54 +
membranous +  and scarious +
5 cm50 mm <br />0.05 m <br /> (?) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
scarious-hyaline +
acute +  and prow--shaped +
Robert J. Soreng +
(L.) Lej. +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
not branching +
intravaginal +, extravaginal +, branching +  and basal +
not swollen +, compressed +  and terete +
swelling +
not evident +
involute +, folded +  and flat +
subequal +
1 cm10 mm <br />0.01 m <br /> (?) +
flexuous +  and straight +
ascending;spreading +
hispidulous +, glabrous +, smooth or +  and sparsely densely scabrous +
angled +  and terete +
2 cm20 mm <br />0.02 m <br /> (9 cm90 mm <br />0.09 m <br />) +
compressed +  and terete +
folded +  and involute +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
unbranched +  and hollow +
compressed +  and terete +
25 cm250 mm <br />0.25 m <br /> (80 cm800 mm <br />0.8 m <br />) +
not woody +
Conn. +, N.J. +, N.Y. +, Wash. +, Va. +, Del. +, D.C. +, Wis. +, W.Va. +, Pacific Islands (Hawaii) +, Mass. +, Maine +, N.H. +, R.I. +, Vt. +, Fla. +, Wyo. +, N.Mex. +, Tex. +, La. +, Puerto Rico +, Tenn. +, N.C. +, S.C. +, Pa. +, Calif. +, Nev. +, Colo. +, Alaska +, Ill. +, Md. +, Minn. +, Mont. +, Ala. +, Ark. +, Ariz. +, Ga. +, Iowa +, Idaho +, Ind. +, Kans. +, Ky. +, Mich. +, Mo. +, Miss. +, N.Dak. +, Nebr. +, Ohio +, Okla. +, Oreg. +, S.Dak. +, Utah +, Alta. +, B.C. +, Greenland +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +  and Yukon +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 5 +
compressed +
reduced +
1-3(5)-veined +
usually distinctly shorter +
shorter or longer +
subtending +
keeled +, lanceolate +  and narrowly lanceolate +
unequal +  and subequal +
distributed +
straight +, sinuous +  and curving +
erect +  and appressed +
uncinate +
slender +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
milky white +  and slightly greenish +
puberulent +  and long-villous +
5(7-11)-veined +
purple-tinged +  and green +
hairy +, glabrous +  and chartaceous +
muriculate +
keeled +  and lanceolate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
membranous +
erose +  and entire +
white +  and milky white or hyaline +
glabrous +  and ciliolate +
obtuse +, truncate +  and rounded +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
sickle--shaped +, usually narrowly lanceolate +  and lanceolate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
muriculate +  and smooth +
1 +  and 2 +
compressed +  and terete +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
20 cm200 mm <br />0.2 m <br /> (?) +
pyramidal +
8 cm80 mm <br />0.08 m <br /> (18 cm180 mm <br />0.18 m <br />) +
dry +  and fleshy +
hairy +, infrequently sparsely +  and glabrous +
terete +  and slightly compressed +
not bulbiferous +
several +  and many +
lanceolate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Poa angustifolia +
Poa pratensis subsp. angustifolia +
Poa pratensis +
subspecies +
membranous +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
parallel +  and converging +
anthocyanic +  and green +
aquatic +  and terrestrial +