Poa cusickii subsp. pallida

Soreng
Endemic
Treatment appears in FNA Volume 24. Treatment on page 560.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants densely tufted. Basal branching intravaginal. Culms 10-40 (55) cm, mostly erect, with 0 (1) scarcely exserted nodes. Sheaths closed for 1/4-2/3 their length, distal sheath lengths 3.6-10 times blade lengths; innovation blades 0.5-1 mm wide, apices usually narrowly prow-shaped; cauline blades usually less than 1.5 mm wide, flat, folded, or involute, usually narrowly prow-shaped, infrequently broadly prow-shaped, flag leaf-blades 0.5-2 (3) cm. Panicles 2-6 cm, contracted, with 10-40 spikelets; nodes with 1-3 branches; branches 0.5-1.7 cm, stout, moderately to densely scabrous, with 2-5 spikelets. Spikelets 4-10 mm. Calluses glabrous; lemmas 4-7 mm, glabrous; anthers vestigial (0.1-0.2 mm) or 2-3.5 mm. 2n = 56, 56+11, 59.

Discussion

Poa cusickii subsp. pallida grows in forb-rich mountain grasslands to alpine habitats, from the southern Yukon Territory to California, across the Great Basin and through the Rocky Mountains to central Colorado. It is found mainly east and north of subsp. cusickii, but pistillate plants extend into the range of that subspecies in the eastern alpine peaks of California, Nevada, and Oregon. The shorter branch length serves to distinguish it from the narrow-panicled subsp. cusickii forms in most cases. It hybridizes with P. fendleriana (p. 556), forming P. xnematophylla (see next). The hybrids may have hairy lemmas or, less often, broader leaf blades and glabrous lemmas. Poa cusickii subsp. pallida was included in Hitchock's (1951) circumscription of Poa pringlei, along with P. keckii and P. suksdorfii.

Selected References

None.

Lower Taxa

None.

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

59 +, 11 +  and 56 +
membranous +  and scarious +
glabrous +, hispidulous +  and softly puberulent +
5 cm50 mm <br />0.05 m <br /> (?) +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
scarious-hyaline +
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 +
5 cm50 mm <br />0.05 m <br /> (?) +
ascending;erect +
hispidulous +, glabrous +, scabrous +  and smooth +
terete +  and angled +
slender +  and stout +
0.5 cm5 mm <br />0.005 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
compressed +  and terete +
prow--shaped +, involute +, folded +  and flat +
soft +  and firm +
0 cm0 mm <br />0 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
glabrous +, scabrous +  and smooth +
unbranched +  and hollow +
10 cm100 mm <br />0.1 m <br /> (60 cm600 mm <br />0.6 m <br />) +
compressed +  and terete +
10 cm100 mm <br />0.1 m <br /> (40 cm400 mm <br />0.4 m <br />) +
not woody +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
Nev. +, Colo. +, Wash. +, Wyo. +, Utah +, Calif. +, Oreg. +, Mont. +, Alta. +, B.C. +, Man. +, Sask. +, Yukon +, Idaho +  and N.Dak. +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 6 +
compressed +
reduced +
2mm +  and 10mm +
1-3(5)-veined +
shorter or longer +
subtending +
keeled +  and lanceolate +
unequal +
distributed +
0 +  and 1/4 +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (?) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
milky white +  and slightly greenish +
obscure +  and prominent +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
5(7-11)-veined +
keeled +, lanceolate +  and broadly lanceolate +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
membranous +  and thinly membranous +
erose +  and entire +
colorless +  and milky white +
ciliolate +  and glabrous +
truncate +  and acuminate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
milky white +  and slightly greenish +
concealed +  and prominent +
0 +  and 2 +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
12 cm120 mm <br />0.12 m <br /> (?) +
narrowly lanceoloid +  and ovoid +
2 cm20 mm <br />0.02 m <br /> (6 cm60 mm <br />0.06 m <br />) +
dry +  and fleshy +
hairy +, glabrous +, scabrous +  and smooth +
glabrous +, scabrous +  and smooth +
rhizomatous +  and stoloniferous +
not bulbiferous +
compressed +, broadly lanceolate +  and narrowly ovate +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Poa cusickii subsp. pallida +
Poa cusickii +
subspecies +
membranous +
5-veined +  and 3-veined +
parallel +  and converging +
aquatic +  and terrestrial +