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Pacific brome

Columbia brome, Columbian brome, common brome

Habit Plants perennial; not rhizomatous. Plants perennial; not rhizomatous.
Culms

60-170 cm, erect;

nodes (5)6-8, pubescent;

internodes usually glabrous, sometimes pubescent near the nodes.

60-120 cm, erect or spreading;

nodes (3)4-6(7), usually pilose;

internodes glabrous.

Sheaths

pilose, midrib of the culm leaves not abruptly narrowed just below the collar;

auricles absent;

ligules 2-4 mm, glabrous, truncate, erose or lacerate;

blades 20-35(37) mm long, 6-16 mm wide, flat, abaxial surfaces glabrous, adaxial surfaces pilose.

pilose or glabrous;

auricles absent;

ligules 2-6 mm, glabrous, obtuse or truncate, erose or lacerate;

blades 13-25(33) cm long, to 14 mm wide, flat, abaxial surfaces usually glabrous, sometimes pilose, adaxial surfaces usually pilose, sometimes glabrous.

Panicles

10-25 cm, open, nodding;

branches ascending, spreading, or drooping.

10-15 cm, open;

branches ascending to drooping.

Spikelets

20-30 mm, elliptic to lanceolate, terete to moderately laterally compressed, with (4)6-10 florets.

15-30 mm, elliptic to lanceolate, terete to moderately laterally compressed, with (3)4-9 florets.

Glumes

pubescent;

lower glumes 6-8.5 mm, 1(3)-veined;

upper glumes 8-11.5 mm, 3-veined, not mucronate;

lemmas 10-12 mm, lanceolate, rounded over the midvein, backs pubescent, margins more densely so, apices acute, entire;

awns 3.5-7 mm, straight, arising less than 1.5 mm below the lemma apices;

anthers 2-4 mm.

glabrous or pilose;

lower glumes 5-8 mm, 1(3)-veined;

upper glumes 8-12 mm, 3-veined;

lemmas 8-15 mm, lanceolate, rounded over the midvein, backs sparsely hairy or glabrous, margins usually coarsely pubescent, sometimes glabrous, apices subulate to acute, entire;

awns (4)6-12 mm, straight, arising less than 1.5 mm below the lemma apices;

anthers 2-4 mm.

2n

= 28.

= 14.

Bromus pacificus

Bromus vulgaris

Distribution
from FNA
AK; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; MT; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Bromus pacificus grows in moist thickets, openings, and ravines along the Pacific coast from southeastern Alaska to northern California, with a few occurrences further inland.

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

Bromus vulgaris grows in shaded or partially shaded, often damp, coniferous forests along the coast, and inland in montane pine, spruce, fir, and aspen forests, from sea level to about 2000 m. Its range extends from coastal British Columbia eastward to southwestern Alberta and southward to central California, northern Utah, and western Wyoming.

Varieties have been described within Bromus vulgaris; because their variation is overlapping, none are recognized here.

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

Source FNA vol. 24, p. 218. FNA vol. 24, p. 216.
Parent taxa Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Bromopsis Poaceae > subfam. Pooideae > tribe Bromeae > Bromus > sect. Bromopsis
Sibling taxa
B. aleutensis, B. anomalus, B. arenarius, B. arizonicus, B. arvensis, B. berteroanus, B. briziformis, B. carinatus, B. caroli-henrici, B. catharticus, B. ciliatus, B. commutatus, B. danthoniae, B. diandrus, B. erectus, B. frondosus, B. grandis, B. hallii, B. hordeaceus, B. inermis, B. japonicus, B. kalmii, B. laevipes, B. lanatipes, B. lanceolatus, B. latiglumis, B. lepidus, B. madritensis, B. maritimus, B. mucroglumis, B. nottowayanus, B. orcuttianus, B. polyanthus, B. porteri, B. pseudolaevipes, B. pubescens, B. pumpellianus, B. racemosus, B. ramosus, B. richardsonii, B. riparius, B. rubens, B. scoparius, B. secalinus, B. sitchensis, B. squarrosus, B. sterilis, B. suksdorfii, B. tectorum, B. texensis, B. vulgaris
B. aleutensis, B. anomalus, B. arenarius, B. arizonicus, B. arvensis, B. berteroanus, B. briziformis, B. carinatus, B. caroli-henrici, B. catharticus, B. ciliatus, B. commutatus, B. danthoniae, B. diandrus, B. erectus, B. frondosus, B. grandis, B. hallii, B. hordeaceus, B. inermis, B. japonicus, B. kalmii, B. laevipes, B. lanatipes, B. lanceolatus, B. latiglumis, B. lepidus, B. madritensis, B. maritimus, B. mucroglumis, B. nottowayanus, B. orcuttianus, B. pacificus, B. polyanthus, B. porteri, B. pseudolaevipes, B. pubescens, B. pumpellianus, B. racemosus, B. ramosus, B. richardsonii, B. riparius, B. rubens, B. scoparius, B. secalinus, B. sitchensis, B. squarrosus, B. sterilis, B. suksdorfii, B. tectorum, B. texensis
Synonyms Bromopsis pacifica B. ciliatus var. glaberrimus
Name authority Shear (Hook.) Shear
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