Bromus porteri
Bromus polyanthus
nodding brome, Porter brome, Porter's brome
Colorado brome, great-basin brome
30-100 cm, erect;
nodes (2)3-4(5), glabrous or pubescent;
internodes mostly glabrous, puberulent near the nodes.
60-120 cm tall, to 3 mm thick, erect, glabrous or puberulent.
glabrous or pilose, midrib of the culm leaves not abruptly narrowed just below the collar;
auricles absent;
ligules to 2.5 mm, glabrous, truncate or obtuse, erose or lacerate;
blades (3)10-25(35) cm long, 2-5(6) mm wide, flat, not glaucous, both surfaces usually glabrous, sometimes the adaxial surface pilose.
usually smooth or scabrous, sometimes hairy except at the throat;
auricles absent;
ligules (1)2-2.5 mm, glabrous, obtuse, erose;
blades 10-31 cm long, 2-9 mm wide, flat, sometimes scabrous, usually glabrous, rarely puberulent to pubescent near the collar.
7-20 cm, open, nodding, often 1-sided;
branches slender, ascending to spreading, often recurved and flexuous.
10-20 cm, open to somewhat contracted;
lower branches shorter than 10 cm, (1)2-3 per node, erect, ascending or spreading, with 1-2 spikelets variously distributed.
12-38 mm, elliptic to lanceolate, terete to moderately laterally compressed, with (3)5-11(13) florets.
20-35 mm, shorter than at least some pedicels and branches, elliptic to lanceolate, strongly laterally compressed, not crowded or overlapping, with 6-11 florets.
usually pubescent, rarely glabrous;
lower glumes 5-7(9) mm, usually 3-veined, sometimes 1-veined;
upper glumes 6-10 mm, 3-veined, not mucronate;
lemmas 8-14 mm, elliptic, rounded over the midvein, usually pubescent or pilose, margins often with longer hairs, backs and margins rarely glabrous, apices acute or obtuse to truncate, entire;
awns (1)2-3(3.5) mm, straight, arising less than 1.5 mm below the lemma apices;
anthers (1)2-3 mm.
smooth or scabrous;
lower glumes (5.5)7-10(11.5) mm, 3-veined;
upper glumes (7.5) 9-11(12.5) mm, 5-7-veined, shorter than the lowest lemma;
lemmas 12-15 mm, lanceolate, laterally compressed, strongly keeled at least distally, glabrous, sometimes scabrous, 7-9-veined, veins usually not raised or riblike, apices entire or with acute teeth, teeth shorter than 1 mm;
awns 4-7 mm;
anthers 1-5 mm.
= 14.
= 56.
Bromus porteri
Bromus polyanthus
Bromus porteri grows in montane meadows, grassy slopes, mesic steppes, forest edges, and open forest habitats, at 500-3500 m. It is found from British Columbia to Manitoba, and south to California, western Texas, and Mexico. It is closely related to B. anomalus, and has often been included in that species. It differs chiefly in its lack of auricles, and in having culm leaves with midribs that are not narrowed just below the collar.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Bromus polyanthus grows on open slopes and in meadows. It is found primarily in the central Rocky Mountains, but the limits of its range include British Columbia in the north, California in the west, and Arizona, New Mexico, and western Texas in the south. It is not known from Mexico. It intergrades with B. carinatus var. marginatus. Plants with an erect, contracted panicle and awns 4-6 mm long can be called B. polyanthus var. polyanthus; those with with an open, nodding panicle and awns up to 8 mm long can be called B. polyanthus var. paniculatus Shear. Because the variation in both characters is continuous, the varieties are not recognized here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
CA
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
Flora NW
