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bog bluegrass, marsh blue grass, western bog bluegrass

old-pasture blue grass

Habit Plants perennial; dark to light green, often anthocyanic in part; loosely tufted, usually neither stoloniferous nor rhizomatous, occasionally with short, slender rhizomes. Plants perennial; not rhizomatous, not stoloniferous, loosely tufted.
Culms

15-100 cm, slender to middling.

20-95 cm tall, 0.8-1.5 mm thick.

Sheaths

closed for 1/4 - 3/5 their length, terete, smooth or sparsely scabrous, margins not ciliate;

ligules 1.5-4(6) mm, smooth to sparsely scabrous, obtuse to acute;

blades 1-4 mm wide, flat, thin, lax, soft, apices narrowly prow-shaped.

closed for 1/3-2/3 their length;

ligules 0.2-3(4) mm, smooth or sparsely scabrous, truncate to obtuse;

blades 1-3.6 (6) mm wide, flat, thin, lax, veins prominent.

Basal branching

mostly extravaginal.

mainly pseudointravaginal.

Panicles

5-15 cm, lax, open, sparse;

nodes with 1-3(5) branches;

branches (2)3-8 cm, spreading to reflexed, capillary, usually angled, infrequently only sulcate or subterete, angles usually moderately densely scabrous, sometimes only sparsely so, with (3)4-15 spikelets.

4-20(24) cm long, less than 1/4 the plant height, lax;

nodes with 1-3 branches;

branches ascending to spreading, lax, angled, angles prominent, scabrous.

Spikelets

4-8 mm, lanceolate or narrowly lanceolate, green or partly purple to dark purple;

florets 2-5;

rachilla internodes smooth, glabrous.

3-5.6 mm, laterally compressed;

florets 2-5;

rachilla internodes glabrous, usually shorter than 1 mm.

Glumes

subulate to lanceolate, thin, distinctly keeled, keels usually scabrous;

lower glumes subulate to narrowly lanceolate, 1-veined;

upper glumes distinctly shorter than to nearly equaling the lowest lemmas;

calluses sparsely webbed;

lemmas 3-4 mm, lanceolate, often partly purple, distinctly keeled, thin, smooth, or with sparse hooks apically, keels and marginal veins softly puberulent to long-villous, hairs extending 1/4 - 2/3 the keel length, sometimes sparse, lateral veins and intercostal regions glabrous, margins glabrous, infolded, apices sharply acute to acuminate, usually bronze-colored;

palea keels nearly smooth, scabrous, or pectinately ciliate;

anthers 0.2-1.1 mm.

2/3 – 3/4 as long as the adjacent lemmas, distinctly keeled;

lower glumes 1(3)-veined;

upper glumes shorter than or subequal to the lowest lemmas;

calluses webbed;

lemmas 2.4-4 mm, lanceolate to broadly lanceolate, distinctly keeled, usually glabrous, bases of marginal veins rarely sparsely softly puberulent, lateral veins prominent, intercostal regions smooth, minutely bumpy, apices obtuse to sharply acute or acuminate;

palea keels scabrous;

anthers 0.4-1.5 mm.

2n

= 42.

Poa leptocoma

Poa saltuensis

Distribution
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC; YT
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; IA; IL; IN; KY; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; LB; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Poa leptocoma grows around lakes and ponds and along streams, in subalpine and alpine to low arctic habitats, in western North America from Alaska to California and New Mexico, and on the Kamchatka Peninsula, Russia. It often grows with or near P. reflexa (p. 538), from which it differs in its more scabrous panicle branches, shorter anthers, glabrous or pectinately ciliate palea keels, and preference for wet sites. The two also differ in their ploidy level, P. leptocoma being hexaploid, and P. reflexa tetraploid. It differs from P. paucispicula (p. 538) in its more scabrous panicle branches, narrower glumes and lemmas, and its more sparsely hairy calluses and lemmas. Although its chloroplast haplotype is similar to that of species in sect. Oreinos, its ITS sequence is distinct and resembles that of P. paucispicula.

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

Poa saltuensis grows in woodlands of the north-central and northeastern United States and adjacent Canada, extending south to Tennessee. The two subspecies are sometimes treated as species. The variation between the two overlaps and is correlated to some extent with ecology and geography. Poa marcida (p. 512), a western species once included in P. saltuensis, differs in having closed sheaths and attenuate lemmas.

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

Key
1. Anthers 0.4-1 mm long; lemma apices obtuse to acute, firm or scarious for up to 0.25 mm
subsp. languida
1. Anthers 0.9-1.5 mm long; lemma apices acute to acuminate, scarious for 0.25-0.5 mm
subsp. saltuensis
Source FNA vol. 24, p. 573. FNA vol. 24, p. 510.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Poa > subg. Poa > sect. Oreinos 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. 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. 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. 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
Subordinate taxa
P. saltuensis subsp. languida, P. saltuensis subsp. saltuensis
Synonyms P. saltuensis var. microlepis, P. languida
Name authority Trin. Fernald & Wiegand
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