Poa wolfii |
Poa arnowiae |
|
---|---|---|
Wolf's bluegrass |
Wasatch bluegrass |
|
Habit | Plants perennial; not rhizomatous, not stoloniferous, loosely tufted. | Plants perennial; loosely tufted or with solitary shoots, short-rhizomatous. |
Culms | 25-90 cm. |
(15)30-80 cm, erect or the bases decumbent, terete or weakly compressed; nodes terete, 1-3 exserted. |
Sheaths | closed for 1/2 - 3/4 their length, smooth or sparsely scabrous, margins not ciliate; ligules 0.3-2.1 mm, smooth or sparsely scabrous, truncate to obtuse, ciliolate; blades 0.6-3.5 mm wide, flat. |
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. |
Basal branching | mainly pseudointravaginal. |
all or mostly extravaginal. |
Panicles | 7.5-15(18) cm, lax, pyramidal, open, sparse; nodes with 1-3(5) branches; branches 3-8 cm, ascending, straight to spreading, angled, angles prominent, scabrous. |
(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 | 4-6.5 mm, laterally compressed; florets 2-5; rachilla internodes to 1 mm, smooth, glabrous. |
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 | 1/2-1/3 the length of the adjacent lemmas, distinctly keeled, keels scabrous; lower glumes subulate to narrowly lanceolate, (1)3-veined; upper glumes shorter than or subequal to the lowest lemmas; calluses webbed; lemmas (2.5)3.2-4.7 mm, lanceolate, green, distinctly keeled, keels and marginal veins long-villous, hairs extending up almost the whole keel length, lateral veins prominent, intercostal regions smooth, minutely bumpy, usually glabrous, rarely sparsely softly puberulent, apices acute, blunt, or pointed, white, not bronze; palea keels softly puberulent at midlength, apices scabrous; anthers (0.5)0.8-1.2(1.5) mm. |
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 | = 28. |
= unknown. |
Poa wolfii |
Poa arnowiae |
|
Distribution |
AR; IA; IL; IN; MN; MO; OH; VA; WI
|
ID; MT; UT; WY |
Discussion | Poa wolfii is an uncommon species that grows in boggy areas of eastern deciduous forests, primarily west of the Appalachian divide. It differs from P. sylvestris (p. 512) in having fewer branches, larger spikelets, and lemmas that are usually glabrous between the veins. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 514. | FNA vol. 24, p. 543. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Sylvestres | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Madropoa > subsect. Poa |
Sibling taxa | ||
Synonyms | P. curta | |
Name authority | Scribn. | Soreng |
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