Poa lettermanii |
Poa alsodes |
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Letterman bluegrass, Letterman's blue grass |
grove blue grass |
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Habit | Plants perennial; not glaucous; densely tufted, not stoloniferous, not rhizomatous. | Plants perennial; not rhizomatous, not stoloniferous, loosely tufted. |
Culms | 1-12 cm, slender. |
31-126 cm. |
Sheaths | closed for 1/6 – 1/4 their length, terete; ligules 1-3 mm, milky white to hyaline, smooth; blades 0.5-2 mm wide, flat or folded, or slightly inrolled, thin, without papillae (at 100x), apices narrowly prow-shaped. |
closed for 1/2 - 7/8 their length; ligules 0.1-1.7(2.1) mm, smooth or sparsely scabrous, truncate to obtuse; blades 0.8-4.1 mm wide, flat, lax. |
Basal branching | all or mainly intra-vaginal. |
mainly pseudointravaginal. |
Panicles | 1-3 cm, erect, contracted, usually exserted from the sheaths; branches to 1.5 cm, erect to steeply ascending, slender, sulcate or angled, smooth or the angles sparsely scabrous; pedicels shorter than the spikelets. |
11.4-36 cm, erect or lax, narrowly pyramidal, usually open, infrequently contracted; nodes with (2)3-5(7) branches; branches spreading, straight, angled, angles sparsely to moderately scabrous. |
Spikelets | 3-4 mm, laterally compressed, green or anthocyanic; florets 2-3; rachilla internodes shorter than 1 mm, smooth. |
3.5-6.7 mm, laterally compressed; florets 2-4; rachilla internodes glabrous. |
Glumes | usually equaling or exceeding the lowest lemmas, sometimes also equaling or exceeding the upper florets, lanceolate to broadly lanceolate, distinctly keeled, keels smooth; lower glumes 3-veined; calluses glabrous; lemmas 2.5-3 mm, lanceolate, distinctly keeled, thin, usually glabrous, keels and marginal veins rarely sparsely puberulent proximally, apices acute; palea keels scabrous; anthers 0.2-0.8 mm. |
ovate, distinctly keeled, keels scabrous; lower glumes 1-veined; upper glumes shorter than or subequal to the lowest lemmas; calluses webbed; lemmas 2.7-4.2(5) mm, lanceolate, distinctly keeled, keels short-villous to about midlength, marginal and lateral veins glabrous, lateral veins obscure or moderately prominent, intercostal regions glabrous, smooth, apices acute; paleas glabrous or ciliolate over the keels, apices finely scabrous; anthers 0.4-0.8 mm. |
2n | = 14. |
= unknown. |
Poa lettermanii |
Poa alsodes |
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Distribution |
CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC
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CT; DE; IL; IN; KY; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; PA; SC; TN; VA; VT; WI; WV; NB; NS; ON; PE; QC
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Discussion | Poa lettermanii grows on rocky slopes of the highest peaks and ridges in the alpine zone, from northern British Columbia to western Alberta and south to California and Colorado, usually in the shelter of rocks or on mesic to wet, frost-scarred slopes. It is one of only three known diploid Poa species native to the Western Hemisphere. Its glabrous calluses and lemmas usually distinguish it from P. abbreviata (p. 582); it also differs in having flat or folded leaf blades, and shorter spikelets with glumes that are longer than the adjacent florets. Poa montevansii E.H. Kelso is tentatively included here, although its slightly longer lemmas that slightly exceed the glumes suggest that it may represent rare, glabrous forms of P. abbreviata. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Poa alsodes grows in mesic woodlands of eastern Canada and the northeastern United States, extending south to Illinois, Tennessee, and North Carolina, particularly in the Appalachian Mountains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 24, p. 580. | FNA vol. 24. |
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Abbreviatae | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Sylvestres |
Sibling taxa | ||
Synonyms | P. mor.tevansi | |
Name authority | Vasey | A. Gray |
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