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bog bluegrass, eastern bog bluegrass

lax-flower bluegrass, loose-flower blue grass

Habit Plants perennial; usually pale green; loosely tufted, slender, usually neither stoloniferous nor rhizomatous, occasionally with short, slender rhizomes. Plants perennial; green throughout; loosely tufted or with solitary shoots, long-rhizomatous.
Culms

10-55 cm, very slender, weak.

50-120 cm.

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 1/2 - 3/4 their length, usually sparsely to moderately retrorsely scabrous, margins not ciliate;

ligules 2-3.5 mm, smooth or sparsely scabrous, obtuse to acute;

blades 3-8 mm wide, flat, lax, apices narrowly prow-shaped.

Basal branching

mostly extravaginal.

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.

14-30 cm, open, sparse, with 1-3(4) branches per node;

branches (5.5)8-12(15) cm, widely spreading, fairly straight, angled, angles sparsely to moderately scabrous, with 3-13 spikelets.

Spikelets

3.2-5.2 mm, laterally compressed, broadly lanceolate to ovate;

florets 2-3(5);

rachilla internodes smooth, glabrous.

4-8 mm, laterally compressed, rarely bulbiferous;

florets 2-4, usually normal, rarely bulb-forming;

rachilla internodes about 1 mm, smooth, glabrous.

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.

distinctly keeled, keels scabrous;

lower glumes lanceolate, 1-3-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 3.2-6 mm, lanceolate, distinctly keeled, smooth or sparsely finely scabrous, keels and marginal veins long-villous, keels hairy to 2/3 – 3/4 their length, marginal veins sparsely hairy, lateral veins moderately prominent, usually glabrous, rarely sparsely softly puberulent, intercostal regions glabrous, apices acute;

paleas scabrous, glabrous over the keels;

anthers 0.5-1.1 mm.

2n

= unknown.

= ca. 98.

Poa paludigena

Poa laxiflora

Distribution
from FNA
IA; IL; IN; MI; MN; NC; NJ; NY; OH; PA; VA; WI; WV
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; OR; WA; BC
[BONAP county map]
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 laxiflora is restricted to mesic, old growth, mixed conifer forests of the Pacific coast, from Alaska south through the western foothills of the northern Cascades to Oregon. It is not a common species. A bulbiferous specimen was collected in the Queen Charlotte Islands.

Inclusion of Poa laxiflora in Poa sect. Homalopoa is tentative; it may belong to sect. Sylvestres.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 24, p. 572. FNA vol. 24, p. 538.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Oreinos Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Homalopoa
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. 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. 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. 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
Name authority Fernald & Wiegand Buckley
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