Poa bulbosa |
Poa supina |
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bulbous blue grass |
supine bluegrass |
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Habit | Plants perennial; densely tufted, not rhizomatous, not stoloniferous. | Plants perennial; stoloniferous, loosely tufted. | ||||
Culms | 15-60 cm, erect or spreading, bases bulbous. |
8-12(20) cm, slender, bases decumbent, terete or weakly compressed; nodes terete, 1 exserted. |
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Sheaths | closed for about 1/4 their length, terete, lowest sheaths with swollen bases; ligules 1-3 mm, smooth or scabrous, apices obtuse to acute; blades 1-2.5 mm wide, flat, thin, lax, soon withering. |
closed for 1/4-1/3 their length, terete, smooth, glabrous, bases of basal sheaths glabrous, distal sheath lengths 2-4 times blade lengths; collars smooth, glabrous; ligules 0.6-1 mm, smooth, glabrous, truncate; blades 2-3 mm wide, flat, thin, soft, smooth, apices broadly prow-shaped, cauline blades subequal. |
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Basal branching | intravaginal. |
intravaginal. |
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Panicles | 3-12 cm, ovoid; nodes with 2-5 branches; branches ascending to spreading, terete, usually smooth or sparsely scabrous, infrequently moderately scabrous. |
2.5-5 cm, lengths 1-2 times widths, erect, loosely contracted or open, ovoid to pyramidal, sparse, with 10-25(30) spikelets and 1-2 branches per node; branches 1-3 cm, spreading to reflexed, straight, terete, smooth or sparsely scabrous, with 2-5(8) spikelets. |
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Spikelets | 3-5 mm, laterally compressed, usually bulbiferous; florets 3-7, the basal floret, and sometimes additional florets, normal; rachilla internodes smooth, glabrous. |
4-6 mm, laterally compressed; florets 3-7; rachilla internodes smooth, glabrous, more or less concealed, distal internode less than 1/2 the length of the distal lemma. |
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Glumes | keeled, keels scabrous; lower glumes 3-veined; upper glumes shorter than or subequal to the lowest lemmas; calluses webbed or glabrous; lemmas 3-4 mm, lanceolate, keeled, glabrous or the keels and marginal veins short- to long-villous, intercostal regions glabrous or softly puberulent, apices acute; paleas scabrous, keels often softly puberulent at midlength; anthers 1.2-1.5 mm and functional, sometimes aborted late in development, sometimes not developed. |
distinctly keeled, keels smooth; lower glumes 1-veined; calluses glabrous; lemmas 1.7-4 mm, lanceolate, distinctly keeled, smooth throughout, proximal lemmas glabrous throughout or the keels and marginal veins sparsely short-villous, distal lemmas glabrous or the keels and marginal veins short-villous to near the apices, lateral veins moderately prominent, intercostal regions glabrous, margins smooth, glabrous, apices obtuse to acute; palea keels smooth, sometimes sparsely softly puberulent to short-villous; anthers (1.25)1.5-2.5 mm, cylindrical prior to dehiscence, those of the upper 1-2 florets commonly vestigial. |
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2n | = 14, 21, 28, 39, 42, 45. |
= 14. |
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Poa bulbosa |
Poa supina |
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Distribution |
AR; AZ; CA; CO; CT; DE; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; MI; MN; MO; MT; NC; ND; NE; NJ; NM; NV; NY; OH; OK; OR; PA; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY
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Discussion | Poa bulbosa is a European species that is now established in the Flora region. In southern Europe and the Middle East, it is considered an important early spring forage. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Poa supina is native to boreal to alpine regions of Eurasia. Beginning in the 1990s, the cultivar 'Supernova' has been introduced for seeding in wet to moist, cool, shady areas subject to heavy traffic. It has been tested in both Canada and the United States, and is expected to gradually escape cultivation, probably becoming established throughout the cool-temperate portion of the Flora region. Its current distribution is not known. Poa supina differs from P. annua (p. 519), of which is thought to be one of the parents, in having longer anthers and a more stoloniferous habit, as well as in being diploid. It is gynomonoecious. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 24, p. 516. | FNA vol. 24, p. 521. | ||||
Parent taxa | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Arenariae | Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Micrantherae | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Name authority | L. | Schrad. | ||||
Web links |
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