Poa arnowiae

Soreng
Common names: Wasatch bluegrass
Synonyms: Poa curta auct.
Treatment appears in FNA Volume 24. Treatment on page 543.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants perennial; loosely tufted or with solitary shoots, short-rhizomatous. Basal branching all or mostly extravaginal. Culms (15) 30-80 cm, erect or the bases decumbent, terete or weakly compressed; nodes terete, 1-3 exserted. Sheaths closed for 1/2 - 9/10 their length, compressed, smooth, glabrous, bases of basal sheaths glabrous, distal sheath lengths 1-3 times blade lengths; collars smooth, glabrous; ligules 0.5-4 mm, smooth or sparsely scabrous, truncate to obtuse; innovation blades similar to the cauline blades; cauline blades 2-5 mm wide, flat, thin, smooth or sparsely scabrous mainly over the veins, apices broadly prow-shaped, middle and upper cauline blades subequal in length, flag leaf-blades (2.5) 4-7 (11) cm long. Panicles (5) 12-22 cm, usually narrowly pyramidal, open, sparse, with 20-70 spikelets, proximal internodes usually (3.5) 4+ cm, with 2-3 (4) branches per node; branches 3-8 cm, spreading to eventually reflexed, terete or weakly angled, sparsely to moderately scabrous, with 3-12 spikelets. Spikelets 5-9 mm, lengths to 3.5 times widths, laterally compressed, not sexually dimorphic; florets 2-6; rachilla internodes smooth, glabrous, distal internodes 1+ mm. Glumes lanceolate, distinctly keeled; lower glumes 1-3-veined; calluses glabrous; lemmas 3-6.5 mm, lanceolate, distinctly keeled, keels and marginal veins glabrous or short-villous to softly puberulent to 1/3 their length, lateral-veins obscure, intercostal regions glabrous or sparsely hispidulous, rarely softly puberulent, smooth or sparsely finely scabrous, margins glabrous, apices acute; palea keels scabrous, glabrous, intercostal regions glabrous; anthers vestigial (0.1-0.2 mm) or (1.3) 2-3.6 mm. 2n = unknown.

Discussion

Poa arnowiae grows in openings within the coniferous forests of the mountain ranges in southeastern Idaho, northern Utah, and adjacent Wyoming. It is sequentially gynomonoecious.

Poa arnowiae used to be called Poa curta Rydb., but the type of P. curta belongs in P. wheeleri.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.No values specified."decumbent" is not a number.

... more about "Poa arnowiae"
membranous +  and scarious +
hispidulous +, glabrous +, scabrous +  and smooth +
5 cm50 mm <br />0.05 m <br /> (?) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
scarious-hyaline +
acute +  and prow--shaped +
Robert J. Soreng +
Soreng +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
compressed +  and terete +
swelling +
not evident +
involute +, folded +  and flat +
spreading;eventually reflexed +
hispidulous +, glabrous +, smooth or +  and sparsely densely scabrous +
angled +  and terete +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
compressed +  and terete +
Wasatch bluegrass +
unbranched +  and hollow +
terete or +  and weakly strongly compressed +
30 cm300 mm <br />0.3 m <br /> (80 cm800 mm <br />0.8 m <br />) +
not woody +
Mont. +, Wyo. +, Idaho +  and Utah +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 6 +
compressed +
reduced +
1-3(5)-veined +
shorter or longer +
subtending +
keeled +  and lanceolate +
unequal +
distributed +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (?) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
hispidulous +, glabrous +, scabrous +  and smooth +
milky white +  and slightly greenish +
glabrous +, scabrous +, smooth +, puberulent +  and hispidulous +
short-villous +  and softly puberulent +
5(7-11)-veined +
hairy +, glabrous +  and chartaceous +
keeled +  and lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
membranous +
erose +  and entire +
white +  and milky white or hyaline +
puberulent +, glabrous +, scabrous +  and smooth +
truncate +  and obtuse +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
milky white +  and slightly greenish +
short-villous +  and softly puberulent +
concealed +  and prominent +
1 +  and 3 +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
5 cm50 mm <br />0.05 m <br /> (?) +
nodding +  and erect +
pyramidal +
12 cm120 mm <br />0.12 m <br /> (22 cm220 mm <br />0.22 m <br />) +
dry +  and fleshy +
compressed +
short-rhizomatous +
not bulbiferous +
3 +  and 12 +
compressed +
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Poa curta +
Poa arnowiae +
Poa subsect. Poa +
species +
membranous +
parallel +  and converging +
with solitary shoots +  and tufted +
aquatic +  and terrestrial +