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bulbous blue grass

Wolf's bluegrass

Habit Plants perennial; densely tufted, not rhizomatous, not stoloniferous. Plants perennial; not rhizomatous, not stoloniferous, loosely tufted.
Culms

15-60 cm, erect or spreading, bases bulbous.

25-90 cm.

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 1/2 - 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.

Basal branching

intravaginal.

mainly pseudointravaginal.

Panicles

3-12 cm, ovoid;

nodes with 2-5 branches;

branches ascending to spreading, terete, usually smooth or sparsely scabrous, infrequently moderately scabrous.

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.

Spikelets

3-5 mm, laterally compressed, usually bulbiferous;

florets 3-7, the basal floret, and sometimes additional florets, normal;

rachilla internodes smooth, glabrous.

4-6.5 mm, laterally compressed;

florets 2-5;

rachilla internodes to 1 mm, smooth, glabrous.

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.

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.

2n

= 14, 21, 28, 39, 42, 45.

= 28.

Poa bulbosa

Poa wolfii

Distribution
from FNA
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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from FNA
AR; IA; IL; IN; MN; MO; OH; VA; WI
[WildflowerSearch map]
[BONAP county map]
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 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.)

Key
1. Spikelets not bulbiferous
subsp. bulbosa
1. All or some spikelets bulbiferous
subsp. vivipara
Source FNA vol. 24, p. 516. FNA vol. 24, p. 514.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Arenariae Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Sylvestres
Sibling taxa
P. abbreviata, P. alpina, P. alsodes, P. ammophila, P. annua, P. arachnifera, P. arctica, P. arida, P. arnowiae, P. atropurpurea, P. autumnalis, P. bigelovii, P. bolanderi, P. chaixii, P. chambersii, P. chapmaniana, P. compressa, P. confinis, P. curtifolia, P. cusickii, P. cuspidata, P. diaboli, P. douglasii, P. eminens, P. fendleriana, P. glauca, P. hartzii, P. howellii, P. infirma, P. interior, P. keckii, P. kelloggii, P. laxa, P. laxa × glauca, P. laxiflora, P. leibergii, P. leptocoma, P. lettermanii, P. macrantha, P. macrocalyx, P. marcida, P. napensis, P. nemoralis, P. nervosa, P. occidentalis, P. paludigena, P. palustris, P. paucispicula, P. piperi, P. porsildii, P. pratensis, P. pringlei, P. pseudoabbreviata, P. reflexa, P. rhizomata, P. saltuensis, P. secunda, P. sierrae, P. stebbinsii, P. stenantha, P. strictiramea, P. sublanata, P. suksdorfii, P. supina, P. sylvestris, P. tenerrima, P. tracyi, P. trivialis, P. unilateralis, P. wheeleri, P. wolfii, P. ×gaspensis, P. ×limosa, P. ×nematophylla
P. abbreviata, P. alpina, P. alsodes, P. ammophila, P. annua, P. arachnifera, P. arctica, P. arida, P. arnowiae, P. atropurpurea, P. autumnalis, P. bigelovii, P. bolanderi, P. bulbosa, P. chaixii, P. chambersii, P. chapmaniana, P. compressa, P. confinis, P. curtifolia, P. cusickii, P. cuspidata, P. diaboli, P. douglasii, P. eminens, P. fendleriana, P. glauca, P. hartzii, P. howellii, P. infirma, P. interior, P. keckii, P. kelloggii, P. laxa, P. laxa × glauca, P. laxiflora, P. leibergii, P. leptocoma, P. lettermanii, P. macrantha, P. macrocalyx, P. marcida, P. napensis, P. nemoralis, P. nervosa, P. occidentalis, P. paludigena, P. palustris, P. paucispicula, P. piperi, P. porsildii, P. pratensis, P. pringlei, P. pseudoabbreviata, P. reflexa, P. rhizomata, P. saltuensis, P. secunda, P. sierrae, P. stebbinsii, P. stenantha, P. strictiramea, P. sublanata, P. suksdorfii, P. supina, P. sylvestris, P. tenerrima, P. tracyi, P. trivialis, P. unilateralis, P. wheeleri, P. ×gaspensis, P. ×limosa, P. ×nematophylla
Subordinate taxa
P. bulbosa subsp. bulbosa, P. bulbosa subsp. vivipara
Name authority L. Scribn.
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