Poa stenantha |
Poa ×gaspensis |
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narrow-flower bluegrass, northern bluegrass |
Gaspé Peninsula bluegrass |
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Habit | Plants perennial; glaucous or not; densely to loosely tufted, not stoloniferous, not rhizomatous. | Plants perennial; densely to loosely tufted, rhizomatous. | ||||
Culms | 20-60(100) cm, bases decumbent or sometimes erect, terete, with 1-2 exserted nodes. |
15-50 cm, erect or the bases decumbent. |
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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. |
closed for 1/4-1/2 their length, terete; ligules acute; blades flat, thin, apices broadly prow-shaped. |
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Basal branching | mostly extravaginal, some intravaginal. |
intra- and extravaginal. |
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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. |
erect, narrowly lanceoloid to ovoid, contracted, with 2-4 branches per node; branches ascending to spreading, sparsely scabrous. |
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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. |
3.5-6 mm, laterally compressed, with 3-4 florets. |
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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. |
broadly lanceolate, distinctly keeled, distinctly scabrous on the distal 1/3; lower glumes 3-veined; calluses shortly webbed; lemmas 2.5-4.5 mm, broadly lanceolate, keeled, keels and marginal veins long-villous, intercostal regions sofdy puberulent; palea keels scabrous, long-villous at midlength; anthers 1.2-1.4 mm. |
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2n | = 42, [81, 84, 86?]. |
= unknown. |
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Poa stenantha |
Poa ×gaspensis |
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Distribution |
AK; CO; ID; MT; OR; UT; WA; AB; BC
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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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Poa ×gaspensis is found in the coastal mountains of the Gaspe Pennisula. There are few plants that fit the description. It seems to consist of hybrids between P. pratensis subsp. alpigena (p. 525) and P. alpina (p. 518). Poa xgaspensis differs from P. alpina in its extravaginal branching, rhizomatous habit, and webbed calluses; from P. pratensis in its acute ligules and more pubescent lemmas; and from P. arctica (p. 529) in its sharply keeled, more scabrous glumes and its spikelet shape, which approaches those of P. alpina and P. pratensis. Poa ×gaspensis is a named intersectional hybrid (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 592. | FNA vol. 24. | ||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Secundae > subsect. Halophytae | Poaceae > subfam. Pooideae > tribe Poeae > Poa | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | P. macroclada | |||||
Name authority | Trin. | Fernald | ||||
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