Poa arctica subsp. grayana

(Vasey) Á. Löve , D. Love & B.M. Kapoor
Synonyms: Poa grayana
Treatment appears in FNA Volume 24. Treatment on page 532.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants sometimes glaucous; densely to loosely tufted, rhizomatous, rhizomes short or long, usually well developed, culms solitary or a few together. Culms 20-60 cm, bases decumbent, not wiry. Sheaths closed for 1/4-2/5 their length; ligules (2) 3-7 mm, smooth, obtuse to acute; blades 1-3 mm wide, flat or folded. Panicles lax to erect, open; branches ascending or widely spreading, somewhat sinuous and flexuous to fairly straight, smooth to sparsely scabrous, proximal branches 2/5 – 1/2 the panicle length. Spikelets (4) 4.5-7 mm, not bulbiferous; rachilla internodes usually glabrous, infrequently sparsely softly puberulent; calluses glabrous; lemmas (2.7) 3-5 mm; palea keels puberulent to long-villous at midlength; anthers usually fully developed. 2n = 36?

Discussion

Poa arctica subsp. grayana grows only in the alpine regions of the middle and southern Rocky Mountains of Utah, Wyoming, Colorado, and New Mexico. It is characterized by its glabrous calluses, densely hairy lemmas, and paleas that are densely hairy between the keels. It has less wiry culms, and panicles with more flexuous branches, than subsp. aperta and, like that subspecies, can be difficult to distinguish from P. arida (p. 599).

Selected References

None.

Lower Taxa

None.

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

membranous +  and scarious +
hairy +, scabrous +  and smooth +
5 cm50 mm <br />0.05 m <br /> (?) +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
scarious-hyaline +
acute +, prow--shaped +, lacerate +, entire +, usually rounded +  and obtuse or acute +
Robert J. Soreng +
(Vasey) Á. Löve , D. Love & B.M. Kapoor +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
folded +  and flat +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
flexuous +  and fairly straight +
spreading;ascending +
hispidulous +, glabrous +, smooth or +  and sparsely densely scabrous +
scabrous +  and smooth to sparsely +
1.5 cm15 mm <br />0.015 m <br /> (6 cm60 mm <br />0.06 m <br />) +
compressed +  and terete +
reduced +  and subequal +
unbranched +  and hollow +
ascending +  and erect +
compressed +  and terete +
slender +  and stout +
20 cm200 mm <br />0.2 m <br /> (60 cm600 mm <br />0.6 m <br />) +
not woody +
Mont. +, Wyo. +, Colo. +, N.Mex. +, Wash. +, Utah +, Alaska +, Alta. +, B.C. +, Greenland +, Man. +, Nfld. and Labr. +, N.W.T. +, Nunavut +, Ont. +, Que. +, Sask. +, Yukon +, Idaho +  and Nev. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
3 +  and 6 +
compressed +
reduced +
1-3(5)-veined +
shorter or longer +
subtending +
lanceolate +  and broadly lanceolate distinctly or weakly keeled +
subequal +  and unequal +
distributed +
uncinate +
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 (?) +
milky white +  and slightly greenish +
glabrous +, puberulent +, short-villous +  and softly puberulent +
prominent +  and pronounced +
5(7-11)-veined +
hairy +, glabrous +  and chartaceous +
keeled +, lanceolate +  and broadly lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
membranous +
erose +  and entire +
white +  and milky white or hyaline +
obtuse +  and acute +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
concealed +  and prominent +
0 +  and 5 +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
2 cm20 mm <br />0.02 m <br /> (?) +
ovoid +  and broadly pyramidal +
3.5 cm35 mm <br />0.035 m <br /> (15 cm150 mm <br />0.15 m <br />) +
dry +  and fleshy +
1.5 cm15 mm <br />0.015 m <br /> (?) +
puberulent +  and glabrous +
not bulbiferous +
compressed +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Poa grayana +
Poa arctica subsp. grayana +
Poa arctica +
subspecies +
membranous +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
parallel +  and converging +
aquatic +  and terrestrial +