Poa paludigena |
Poa stebbinsii |
|
---|---|---|
bog bluegrass, eastern bog bluegrass |
Stebbins' blue grass |
|
Habit | Plants perennial; usually pale green; loosely tufted, slender, usually neither stoloniferous nor rhizomatous, occasionally with short, slender rhizomes. | Plants perennial; densely tufted, not stoloniferous, not rhizomatous. |
Culms | 10-55 cm, very slender, weak. |
10-30(40) cm, mostly erect, with 0-1 slightly exposed nodes. |
Sheaths | closed for 1/4 - 3/5 their length, terete, smooth or sparsely scabrous, margins not ciliate; ligules 0.5-2 mm, smooth or sparsely scabrous, truncate; blades 0.8-2 mm wide, flat, thin, soft, apices narrowly prow-shaped. |
closed for 1/5 – 2/5 their length, terete, smooth and glabrous, bases of basal sheaths glabrous, distal sheath lengths 1.4-3.6 times blade lengths; collars smooth, glabrous; ligules of cauline leaves 3-8 mm, colorless, transparent, smooth, margins decurrent, apices obtuse to acuminate, ligules of the innovation leaves 2.5-6 mm; innovation blades similar to the cauline blades, 1-2 mm wide, involute, moderately thick, abaxial surfaces smooth, adaxial surfaces smooth or sparsely scabrous, sometimes sparsely hispidulous; cauline blades gradually reduced in length distally, 1-2 mm wide, folded or involute, moderately thick, soft, abaxial surfaces smooth, apices narrowly prow-shaped. |
Basal branching | mostly extravaginal. |
strictly extravaginal. |
Panicles | 3-8(12) cm, lax, open, sparse; nodes with 1-2(3) branches; branches (2)3-7 cm, spreading to reflexed, capillary, angled, angles scabrous. |
3-7 cm, erect or slightly nodding, narrowly lanceoloid to narrowly ovoid, often interrupted, contracted to loosely contracted, with 9-38(60) spikelets; nodes with 1-2 branches; branches 0.5-1.5(2.5) cm, erect at maturity, slender, terete to sulcate or weakly angled, sparsely to moderately scabrous, with 1-5 spikelets. |
Spikelets | 3.2-5.2 mm, laterally compressed, broadly lanceolate to ovate; florets 2-3(5); rachilla internodes smooth, glabrous. |
4-6.5 mm, lengths to 3.5 times widths, lanceolate, laterally compressed, not sexually dimorphic, usually strongly anthocyanic, less so in pistillate plants; florets 2-4; rachilla internodes smooth, glabrous or sparsely hispidulous. |
Glumes | narrowly lanceolate to lanceolate, thin, distinctly keeled, keels scabrous; lower glumes 1-3-veined; upper glumes shorter than or subequal to the adjacent lemmas; calluses sparsely webbed; lemmas 2.5-4 mm, lanceolate, green, distinctly keeled, keels and marginal veins short-villous, extending 2/3 – 4/5 the keel length, lateral veins fairly prominent, intercostal regions glabrous, apices obtuse to broadly acute, white, faintly bronze-colored or not; palea keels scabrous; anthers 0.2-0.8 mm. |
unequal, lanceolate, thin, lustrous, distinctly keeled, keels and distal surface smooth or sparsely finely scabrous; lower glumes 3-veined, distinctly shorter than the lowest lemmas; calluses glabrous; lemmas 3.5-5.5 mm, lanceolate, distinctly keeled, thinly membranous, smooth or sparsely scabrous, glabrous, lateral veins moderately prominent, margins glabrous, apices acute; palea keels finely scabrous; anthers vestigial (0.1-0.2 mm) or 2-4.5 mm. |
2n | = unknown. |
= 42, 81 (both counts of uncertain application). |
Poa paludigena |
Poa stebbinsii |
|
Distribution |
IA; IL; IN; MI; MN; NC; NJ; NY; OH; PA; VA; WI; WV
|
CA |
Discussion | Poa paludigena is an inconspicuous species restricted to the northeastern United States. It grows in shady bogs and fens, often underneath other plants. Poa trivialis (p. 568) sometimes grows with P. paludigena; the former has distinctly longer ligules and anthers. Plants from the middle Appalachian Mountains are sometimes confused with P. sylvestris (p. 512). Poa paludigena is generally shorter and more slender, has shorter panicles with only 1-2 branches per node, is glabrous between the lemma veins and on the palea keels, has shorter anthers, and grows in colder habitats. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Poa stebbinsii is endemic to the high Sierra Nevada. It grows primarily in the outer margins of subalpine wet meadows, and is gynodioecious. It is easily recognized by its long hyaline ligules, thin glabrous lemmas, and the absence of intravaginal shoots. It was confused with P. bansenii Scribn. [= P. cusickii subsp. cusickii] by Keck in Munz (1959), and with P. leibergii by Hitchcock (1951). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 572. | FNA vol. 24, p. 564. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Oreinos | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Madropoa > subsect. Epiles |
Sibling taxa | ||
Name authority | Fernald & Wiegand | Soreng |
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