Plants usually perennial, sometimes annual. Spikelets elliptic to lanceolate, more or less terete initially, sometimes becoming laterally compressed at anthesis, with (3)4-14(16) florets. Lower glumes 1-3-veined; upper glumes 3-5-veined; lemmas elliptic to lanceolate, rounded over the midvein, apices subulate, acute, obtuse or rounded, entire or slightly emarginate; awns straight, arising less than 1.5 mm below the lemma apices.

Discussion

Bromus sect. Bromopsis is sometimes incorrectly called sect. Pnigma Dumort. It is native to Eurasia as well as to North and South America, and has about 90 species.

Selected References

None.

Lower Taxa

Bromus anomalus, Bromus ciliatus, Bromus erectus, Bromus frondosus, Bromus grandis, Bromus hallii, Bromus inermis, Bromus kalmii, Bromus laevipes, Bromus lanatipes, Bromus latiglumis, Bromus mucroglumis, Bromus nottowayanus, Bromus orcuttianus, Bromus pacificus, Bromus porteri, Bromus pseudolaevipes, Bromus pubescens, Bromus pumpellianus, Bromus ramosus, Bromus richardsonii, Bromus riparius, Bromus suksdorfii, Bromus texensis, Bromus vulgaris

Key

1	Plants rhizomatous.	> 2
2	Culms 30-90 cm long, forming distinct clumps; rhizomes short	Bromus riparius
2	Culms 50-135 cm long, single or few together; rhizomes short to long-creeping.	> 3
3	Lemma backs sparsely to densely hairy throughout, or on the lower portion and margins, or along the marginal veins and keel; cauline nodes and leaf blades pubescent or glabrous; awns usually present, to 7.5 mm long, sometimes absent	Bromus pumpellianus
3	Lemma backs usually glabrous, occasionally sparsely puberulent at the base and sometimes on the margins; cauline nodes and leaf blades usually glabrous, rarely hairy; awns absent or to 3 mm long	Bromus inermis
1	Plants not rhizomatous.	> 4
4	Anthers (3.5)4-6(6.8) mm long; awns 2.5-7.5 mm long; plants of the Yukon River drainage of Alaska	Bromus pumpellianus
4	Anthers 1-7 mm long; awns 1-12 mm long; plants of various locations in the Flora region, if in the Yukon River drainage of Alaska, anthers 1-1.4 mm long.	> 5
5	Culms with 9-20 nodes; collars and throats densely pilose; auricles 1-2.5 mm long on most lower leaves	Bromus latiglumis
5	Culms with (1)2-9 nodes; collars and throats pubescent or glabrous; auricles, if present, of various lengths.	> 6
6	Most lower glumes within a panicle 3-veined, sometimes some 1-veined.	> 7
7	Most upper glumes within a panicle 5-veined, sometimes some 3-veined.	> 8
8	Awns 1.5-3 mm long; anthers 1.5-2.5 mm long; ligules 0.5-1 mm long	Bromus kalmii
8	Awns 3-7 mm long; anthers 3-6 mm long; ligules to 4.2 mm long.	> 9
9	Glumes glabrous; ligules glabrous	Bromus laevipes
9	Glumes usually pubescent, rarely glabrous; ligules usually pubescent or pilose, sometimes glabrous.	> 10
10	Margins of the glumes and lemmas often bronze-tinged; ligules to 1.5 mm long; auricles usually present on the lower leaves, rarely absent	Bromus pseudolaevipes
10	Margins of the glumes and lemmas not bronze-tinged; ligules 1-3 mm long; auricles sometimes present	Bromus grandis
7	Most upper glumes within a panicle 3-veined, sometimes some 5-veined.	> 11
11	Culms 70-180 cm tall; awns 3-8 mm long; anthers 3-6 mm long.	> 12
12	Lower leaf sheaths pilose, hairs 2-4 mm long; blades glabrous or with pilose margins	Bromus orcuttianus
12	Lower leaf sheaths densely pubescent, hairs to 1 mm long; blades densely pubescent.	> 13
13	Blades 7.5-16.5 cm long; culm nodes 1-2(3)	Bromus hallii
13	Blades (13)18-38 cm long; culm nodes 3-7	Bromus grandis
11	Culms 30-100 cm tall; awns 1—4 mm long; anthers (1)1.5-4 mm long.	> 14
14	Leaf blades often glaucous; glumes usually glabrous, rarely slightly pubescent	Bromus frondosus
14	Leaf blades not glaucous; glumes usually pubescent, rarely glabrous.	> 15
15	Midrib of the culm leaves abruptly narrowed just below the collar; auricles frequently present on the lower leaves; plants of western Texas	Bromus anomalus
15	Midrib of the culm leaves not abruptly narrowed just below the collar; auricles absent; plants of western North America, including Texas	Bromus porteri
6	Most lower glumes within a panicle 1-veined, sometimes some 3-veined.	> 16
16	Upper glumes within a panicle consistently 5-veined; collars with a dense line of hairs; lower sheaths often sericeous; ligules 0.4-1 mm long	Bromus nottowayanus
16	All or most upper glumes within a panicle 3-veined, sometimes some with 2 additional faint lateral veins; collars glabrous or hairy, hairs evenly distributed over the surface, not in a dense line; lower sheaths glabrous or hairy, not sericeous; ligules to 6 mm long.	> 17
17	Plants annual; lemmas glabrous; ligules pubescent	Bromus texensis
17	Plants perennial; lemmas usually pubescent on the backs and/or margins, sometimes glabrous; ligules usually glabrous, sometimes pubescent or pilose.	> 18
18	Awns (4)6-12 mm long; ligules 2-6 mm long	Bromus vulgaris
18	Awns 1-8 mm long; ligules to 4 mm long.	> 19
19	Blades densely pubescent on both surfaces, 7.5-16.5 cm long; anthers 3-6 mm long; awns 3.5-7 mm long	Bromus hallii
19	Blades glabrous or hairy on 1 or both surfaces, (3)5-60 cm long, if 7.5-16.5 cm long and densely pubescent on both surfaces, then anthers 1-4 mm long and/or awns 1-4 mm long.	> 20
20	Panicle branches appressed to slightly spreading; culm nodes 1-4.	> 21
21	Awns 2-5 mm long; anthers 2-3.5 mm long; blades flat	Bromus suksdorfii
21	Awns (4)5-8 mm long; anthers 3-6.5 mm long; blades sometimes involute.	> 22
22	Culms 90-150 cm tall; ligules 1-3 mm long.	Bromus orcuttianus
22	Culms 50-100 cm tall; ligules to 1.5 mm long	Bromus erectus
20	Panicle branches ascending to drooping; culm nodes (1)2-8.	> 21
23	Midrib of the culm leaves abruptly narrowed just below the collar; auricles frequently present on the lower leaves; plants of western Texas	Bromus anomalus
23	Midrib of the culm leaves not abruptly narrowed just below the collar; auricles sometimes present; plants of various distribution, including Texas.	> 24
24	Glumes usually pubescent, rarely glabrous.	> 25
25	Upper glume mucronate	Bromus mucroglumis
25	Upper glume not mucronate.	> 26
26	Awns (1)2-3(3.5) mm long; blades 2-6 mm wide	Bromus porteri
26	Awns 3-7(8) mm long; blades 3-19 mm wide.	> 27
27	Anthers 3-6 mm long; ligules densely pubescent to pilose	Bromus grandis
27	Anthers 2-4(5) mm long; ligules glabrous.	> 28
28	Ligules 2-4 mm long	Bromus pacificus
28	Ligules 0.5-2 mm long	Bromus pubescens
24	Glumes usually glabrous, sometimes pubescent.	> 29
29	Ligules 2-3.5 mm long; auricles present	Bromus ramosus
29	Ligules 0.4-2 mm long; auricles sometimes present.	> 30
30	Lemma margins and backs usually pubescent, sometimes nearly glabrous; awns 2-4 mm long; anthers 1.8-4 mm long	Bromus lanatipes
30	Lemma margins conspicuously hirsute or densely pilose, at least along the lower 1/2, the backs glabrous at least on the lower lemmas in a spikelet; awns 3-5 mm long; anthers 1-2.7 mm long.	> 31
31	Backs of all lemmas glabrous; anthers 1-1.4 mm long; upper glumes 7.1-8.5 mm long	Bromus ciliatus
31	Backs of the upper lemmas in a spikelet hairy; anthers 1.6-2.7 mm long; upper glumes 8.9-11.3 mm long	Bromus richardsonii