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.

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. > 2
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. > 8
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. > 12
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. > 7
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. > 25
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

"decumbent" is not a number.

... more about "Bromus sect. Bromopsis"
membranous +  and scarious +
emarginate +  and entire +
Rounded (?) +, Obtuse (?) +, Acute (?) +  and Subulate (?) +
Leon E. Pavlickf +
Dumort. +
1 (?) +  and 3 (?) +
straight +
distinct +
subterminal +  and terminal +
geniculate +
0 cm0 mm <br />0 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not evident +
cross +, linear +  and narrowly lanceolate +
drooping;reflexed;usually ascending;spreading +
spikelike +
not branching +
ascending +  and erect +
5 cm50 mm <br />0.05 m <br /> (190 cm1,900 mm <br />1.9 m <br />) +
not woody +
Conn. +, Mass. +, N.H. +, N.J. +, N.Y. +, Calif. +, Del. +, N.C. +, Va. +, W.Va. +, Vt. +, D.C +, Wis. +, Colo. +, Kans. +, Nebr. +, Okla. +, Idaho +, Mont. +, Oreg. +, Wash. +, Wyo. +, Pacific Islands (Hawaii) +, N.Mex. +, Utah +, Maine +, R.I. +, Fla. +, Ala. +, Ark. +, Ariz. +, Ga. +, Iowa +, Ill. +, Ind. +, Ky. +, La. +, Md. +, Mich. +, Minn. +, Mo. +, Miss. +, N.Dak. +, Nev. +, Ohio +, Pa. +, S.Dak. +, Tenn. +, Tex. +, Alaska +, S.C. +, Alta. +, B.C. +, Greenland +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, N.W.T. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +  and Yukon +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
4 +  and 14 +
terete +  and laterally compressed +
1-9(11)-veined +
always shorter +  and usually shorter +
lanceolate +
subtending +
pubescent +  and glabrous +
mucronate +  and acute +
unequal +
uncinate +
solid +  and hollow +
pubescent +  and glabrous +
rounded +, elliptic +  and lanceolate +
herbaceous +  and coriaceous +
lacerate +
0 cm0 mm <br />0 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
membranous +
inconspicuous +
lanceolate +
fleshy +  and membranous +
concealed +  and prominent +
2 +  and 1 +
hairy +  and glabrous +
well-developed +
reduced +
dry +  and fleshy +
1 +  and 60 +
not viviparous +
compressed +, terete +, elliptic +  and lanceolate +
0.5 cm5 mm <br />0.005 m <br /> (7 cm70 mm <br />0.07 m <br />) +
1 (?) +  and 3 (?) +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Bromus sect. Bromopsis +
section +
membranous +
annual +  and perennial +
aquatic +  and terrestrial +