Poa stenantha

Trin.
Common names: Narrow-flower bluegrass
Synonyms: Poa macroclada
Treatment appears in FNA Volume 24. Treatment on page 592.

Plants perennial; glaucous or not; densely to loosely tufted, not stoloniferous, not rhizomatous. Basal branching mostly extravaginal, some intravaginal. Culms 20-60 (100) cm, bases decumbent or sometimes erect, terete, with 1-2 exserted nodes. Sheaths closed for 1/10 – 1/5 (1/4) their length, terete, bases of basal sheaths glabrous; ligules 2-5 mm, milky white, smooth or sparsely scabrous, acute to acuminate; innovation blades similar in texture and shape to the cauline blades; cauline blades not greatly reduced upwards, 1.5-4 (5) mm wide, flat or folded, thin, lax, smooth or sparsely scabrous, apices narrowly prow-shaped. Panicles 5-18 (25) cm, lax, loosely contracted to open, sparse, with 20-65 spikelets and usually 2 (7) branches per node; branches 3-15 cm, ascending to spreading, angled, angles finely to coarsely, sparsely to fairly densely scabrous, infrequently smooth, with 3-10 (15) spikelets in the distal 1/2. Spikelets 6-10 mm, lengths 3-3.6 times widths, lanceolate to narrowly ovate, laterally compressed, sometimes bulbiferous, drab, often slightly glaucous; florets 3-4 (7), normal or bulb-forming; rachilla internodes 1.2-2 mm, slightly dorsally compressed, smooth or sparsely muriculate. Glumes subequal, lanceolate to broadly lanceolate, dull, frequently glaucous, obtuse to acute; lower glumes 3-veined; upper glumes (3.7) 4.1-6.5 mm; calluses usually crowned with 0.2-2 mm hairs, sometimes glabrous; lemmas 4-6 mm, lanceolate, distinctly compressed, distinctly keeled, keels, marginal veins, and sometimes the lateral-veins short to long-villous, hairs extending for 3/4 of the keel, intercostal regions glabrous, sparsely puberulent or hispidulous proximally, usually sparsely to moderately densely scabrous distally, hairs distinctly shorter than those of the keel and veins, margins weakly inrolled, broadly scarious, glabrous, apices acute; palea keels scabrous, often softly puberulent at midlength, intercostal regions glabrous or puberulent; anthers 1.2-2 mm, sometimes aborted late in development or undeveloped. 2n = 42, [81, 84, 86?].

Distribution

Colo., Wash., Utah, Alta., B.C., Oreg., Mont., Idaho, Alaska

Discussion

Poa stenantha grows in coastal meadows and on cliffs in subarctic and boreal forests; it is less common in moist, more southern subalpine and low alpine meadows and thickets. Its range extends from western Alaska to the northern Cascades and Rocky Mountains and, as a disjunct, to Patagonia. Poa stenantha was originally described as growing in Kamchatka, Russia, but the Russian plants have since been referred to other species.

Selected References

None.

Key

1 Spikelets not bulbiferous Poa stenantha var. stenantha
1 Spikelets bulbiferous Poa stenantha var. vivipara

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

... more about "Poa stenantha"
86 +, 84 +, [81 +  and 42 +
membranous +  and scarious +
puberulent +, hispidulous +, hairy +  and glabrous +
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 +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
persisting +
not evident +
involute +, folded +  and flat +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
ascending;spreading +
hispidulous +, glabrous +, smooth or +  and sparsely densely scabrous +
3 cm30 mm <br />0.03 m <br /> (15 cm150 mm <br />0.15 m <br />) +
compressed +  and terete +
folded +  and flat +
Narrow-flower bluegrass +
unbranched +  and hollow +
ascending +  and erect +
compressed +, terete +  and capillary +
20 cm200 mm <br />0.2 m <br /> (60 cm600 mm <br />0.6 m <br />) +
not woody +
Colo. +, Wash. +, Utah +, Alta. +, B.C. +, Oreg. +, Mont. +, Idaho +  and Alaska +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
3 +  and 4 +
compressed +
reduced +
bulb-forming +  and normal +
1-3(5)-veined +
shorter or longer +
subtending +
obtuse +  and acute +
subequal +
distributed +
uncinate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
milky white +  and slightly greenish +
puberulent +, glabrous +  and hispidulous +
indistinct +
5(7-11)-veined +
hairy +  and glabrous +
keeled +, compressed +  and lanceolate +
subequal +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
erose +  and entire +
milky white +
ciliolate +  and smooth +
acute +  and acuminate +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
milky white +  and slightly greenish +
concealed +  and prominent +
0 +  and 5 +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
25 cm250 mm <br />0.25 m <br /> (?) +
pyramidal +, narrowly lanceoloid +  and ovoid +
5 cm50 mm <br />0.05 m <br /> (18 cm180 mm <br />0.18 m <br />) +
dry +  and fleshy +
pubescent +, glabrous +, scabrous +  and smooth +
3 +  and 10 +
compressed +, lanceolate +  and narrowly ovate +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Poa macroclada +
Poa stenantha +
Poa subsect. Halophytae +
species +
membranous +
0.41 cm4.1 mm <br />0.0041 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
parallel +  and converging +
branching +, not rhizomatous +  and not stoloniferous +
aquatic +  and terrestrial +
not +  and glaucous +