1	"All or almost all spikelets viviparous, the spikelets producing plantlets [if sexual spikelets are common, take the alternate lead]"	2
1	"Some, usually all, spikelets sexually functional, with 1–25 bisexual or unisexual florets, sometimes with sterile and sexual spikelets mixed within an inflorescence"	4
2	"Panicle branches smooth or slightly scabrous, the scabrules widely spaced; blades with a translucent line on either side of the midvein, apices usually prowlike"	Poa
2	"Panicle branches scabrous; blades without a translucent line on either side of the midvein, apices usually not prowlike"	3
3	"Sheaths closed for 1/2 or more of their length; ligules 0.1–0.6 mm long"	Festuca
3	"Sheaths open; ligules 1.5–13 mm long"	Deschampsia
4	"Inflorescences with 2 morphologically distinct forms of spikelets"	5
4	"Inflorescences with all spikelets morphologically alike"	7
5	"Spikelets in pairs, the pedicels not fused at the base, smooth or slightly scabrous; disarticulation above the glumes and beneath the florets"	Cynosurus
5	"Spikelets in fascicles, the pedicels fused at the base, glabrous, hispid or strigose; disarticulation at the base of the fused pedicels"	6
6	"Secondary panicle branches sharply bent below the pedicels; glumes not winged"	"Lamarckia {Lamarckia aurea}"
6	"Secondary panicle branches straight below the pedicels; glumes winged"	Phalaris
7	"Glumes with pilose awns"	"Lagurus {Lagurus ovatus}"
7	"Glumes, if present, unawned or with glabrous awns"	8
8	"Inflorescences spikes with 1–2(4) spikelets per node, or spikelike racemes with 1 spikelet at all or most nodes"	9
8	"Inflorescences panicles or racemes, with more than 1 spikelet associated with each node"	19
9	"Spikelets with 1 functional floret, sometimes a reduced, sterile floret also present"	10
9	"Spikelets with 2–25 functional florets"	13
10	"Glumes membranous, flexible; all spikelets pedicellate, pedicels 0.5–1 mm long, 0.1–0.2 mm thick"	"Mibora {Mibora minima}"
10	"Glumes coriaceous, stiff; lower spikelets sessile, upper spikelets sometimes pedicellate"	11
11	"Spikelets radial to the rachises, most spikelets with 1 glume, the terminal spikelets with 2 glumes"	"Hainardia {Hainardia cylindrica}"
11	"Spikelets tangential to the rachises, all with 2 glumes"	12
12	"Lemmas unawned"	Parapholis
12	"Lemmas awned, awns 2–4 mm"	"Scribneria {Scribneria bolanderi}"
13	"Lemmas awned from about midlength, awns 8–26 mm long, twisted proximally"	14
13	"Lemmas unawned or apically awned, awns straight"	15
14	"Adaxial surfaces of the leaves ribbed; rachillas pilose on all sides; ligules truncate to rounded, 0.5–1.5 mm long"	Helictotrichon
14	"Adaxial surfaces of the leaves unribbed; rachillas glabrous on the side adjacent to the paleas, hairy elsewhere; ligules acute to truncate, 0.5–7 mm long"	Avenula
15	"Spikelets sessile; lemmas 2–12 mm long"	16
15	"Spikelets subsessile to pedicellate, pedicels 0.5–3 mm long"	17
16	"Spikelets radial to the rachises, most spikelets with 1 glume, only the terminal spikelet with 2 glumes"	Lolium
16	"Spikelets tangential to the rachises, all spikelets with 2 glumes"	"Gaudinia {Gaudinia fragilis}"
17	"Plants perennia"	Festuca
17	"Plants annual"	18
18	"Inflorescences usually exceeded by the leaves; spikelets with (2)3–4(7) florets; lemmas (5)7–9-veined, apices round to emarginate, not bifid; culms usually prostrate or procumbent"	Sclerochloa
18	"Inflorescences usually exceeding the leaves; spikelets with 4–25 florets; lemmas 5-veined, apices acute to obtuse, sometimes bifid; culms procumbent to erect"	Desmazeria
19	"Inflorescences racemes or spikelike panicles, with all branches shorter than 1 cm"	20
19	"Inflorescences panicles, dense to open, sometimes compact, usually at least some branches longer than 1 cm"	39
20	"Leaves usually exceeding the inflorescences; culms usually prostrate to procumbent; lemmas indurate at maturity"	Sclerochloa
20	"Leaves usually exceeded by the inflorescences; culms usually erect or decumbent at the base; lemmas usually membranous or papery, sometimes coriaceous, not indurate"	21
21	"Spikelets disarticulating below the glumes or, if the spikelets are attached to stipes, at the base of the stipes; glume bases sometimes fused"	22
21	"Spikelets disarticulating above the glumes; glume bases not fused"	24
22	"Spikelets weakly laterally compressed, with stipes that fall with the spikelets; glume bases not fused; glumes usually awned"	Polypogon
22	"Spikelets strongly laterally compressed, without stipes; glume bases sometimes fused; glumes unawned or awned"	23
23	"Lemmas dorsally awned; spikelets oval in outline; glumes often connate at the base, often winged distally, keels sometimes ciliate, apices never abruptly truncate"	Alopecurus
23	"Lemmas usually unawned, occasionally subterminally awned; spikelets often U-shaped in outline, sometimes oval; glumes not connate at the base, not winged, often strongly ciliate on the keels and abruptly truncate to an awnlike apex"	Phleum
24	"Spikelets with 2–25 bisexual florets, the sterile or staminate florets, if present, distal to the bisexual florets"	25
24	"Spikelets with 1 bisexual floret, sometimes with 1–2 sterile florets below the bisexual floret, the sterile florets sometimes reduced to lemmas, sometimes resembling tufts of callus hair"	30
25	"Sheaths closed for at least 1/2 their length"	26
25	"Sheaths open for all or almost all of their length"	27
26	"Lemma midveins sometimes excurrent up to 2.2 mm, other veins not excurrent; plants native, arctic"	"Dupontia {Dupontia fisheri}"
26	"Lemmas with 3–5 veins excurrent, forming awnlike teeth; plants cultivated"	Sesleria
27	"Distal lemmas, sometimes all lemmas, awned from below midlength"	Aira
27	"All lemmas unawned or apically awned"	28
28	"Lemmas coriaceous at maturity, unawned, sometimes mucronate"	Desmazeria
28	"Lemmas membranous, apically awned, awns 0.3–22 mm long"	29
29	"Lemma margins involute, not scarious"	Vulpia
29	"Lemma margins flat, scarious"	"Rostraria {Rostraria cristata}"
30	"Spikelets with 1–2 sterile or staminate florets below the bisexual florets, these from larger than to much smaller than the bisexual florets, sometimes resembling tufts of hair; glumes sometimes winged distally"	31
30	"Spikelets without sterile or staminate florets below the bisexual floret; glumes not winged distally"	32
31	"Fresh leaves not sweet-smelling when crushed; sterile lemmas unawned; bisexual lemmas usually hairy, sometimes sparsely so; glumes subequal, sometimes winged distally"	Phalaris
31	"Fresh leaves sweet-smelling when crushed; sterile lemmas awned; bisexual lemmas glabrous; glumes unequal, not winged"	Anthoxanthum
32	"Lemmas dorsally awned, awns geniculate; lateral lemma veins excurrent, forming 4 teeth, teeth sometimes awnlike"	"Bromidium {Bromidium tandilense}"
32	"Lemmas unawned or with only 1 awn, awns not strongly geniculate; lateral lemma veins not excurrent"	33
33	"Spikelets 8–15 mm long; lemmas more than 3/4 as long as the glumes; plants strongly rhizomatous"	Ammophila
33	"Spikelets 1.2–7 mm long; lemmas less than 3/4 as long as the glumes; plants rhizomatous or not"	34
34	"Sheaths closed for at least 1/2 their length"	35
34	"Sheaths open for most of their length"	36
35	"Calluses glabrous; exposed at maturity; lemmas 1–3-veined, unawned; [other genera may develop long caryopses when infected by nematodes or fungi; such caryopses are usually deformed and filled with eggs, larvae, or spores]"	Phippsia
35	"Calluses with a ring of stiff hairs, hairs to about 1 mm long; lemmas 3–11-veined"	Dupontia
36	"Spikelet bases usually U-shaped, sometimes cuneate; glumes equal, midveins usually strongly ciliate"	Phleum
36	"Spikelet bases cuneate; glumes unequal, midveins not strongly ciliate"	37
37	"Both glumes twice as long as the lemmas; lemmas pubescent"	"Gastridium {Gastridium phleoides}"
37	"Glumes from slightly shorter than to slightly longer than the lemmas; lemmas glabrous, sometimes scabridulous or scabrous"	38
38	"Lemma awns 4–16 mm long; plants annual; paleas from 3/4 as long as to slightly longer than the lemmas"	Apera
38	"Lemma awns to 10 mm, if longer than 4 mm, plants perennial and/or paleas less than 1/2 as long as the lemmas"	Agrostis
39	"Caryopses usually as long as or longer than the lemmas, exposed at maturity; lemmas 1–3-veined, unawned; spikelets with 1 floret; sheaths of the flag leaves closed for at least 1/2 their length; calluses glabrous [other genera may develop long caryopses when infected by nematodes or fungi; such caryopses are usually deformed or filled with eggs, larvae, or spores]"	40
39	"Caryopses shorter than the lemmas, concealed at maturity; lemmas 3–11-veined; spikelets with 1 or more florets; leaf sheaths open or closed; calluses glabrous or with hairs"	41
40	"Lemmas 1-veined, narrowed to awnlike apices; sheaths strongly inflated; glumes absent; plants of temperate habitats ... Coleanthus"	"Coleanthus {Coleanthus subtilis}"
40	"Lemmas 1–3-veined, apices acute to rounded; sheaths not inflated; glumes developed, caducous or persistent; plants of arctic or alpine habitats"	Phippsia
41	"Panicle branches secund, appearing 1-sided; spikelets strongly imbricate, subsessile"	42
41	"Panicle branches not secund; spikelets usually widely spaced to somewhat imbricate, usually clearly pedicellate, sometimes subsessile, sometimes on stipes"	45
42	"Culms usually prostrate or procumbent; glumes obtuse to emarginate"	"Sclerochloa {Sclerochloa dura}"
42	"Culms erect or ascending; glumes apiculate to awn-tipped"	43
43	"Lemmas awned, awns of the lowest lemmas 0.3–22 mm long"	Vulpia
43	"Lemmas unawned, sometimes awn-tipped"	44
44	"Spikelets circular to ovate or obovate in outline, with 1–2 florets; glumes almost entirely concealing the sides of the florets; disarticulation below the glumes"	"Beckmannia {Beckmannia syzigachne}"
44	"Spikelets oval in outline, longer than wide, with 2–6 florets; glumes partially exposing the sides of the florets; disarticulation above the glumes"	"Dactylis {Dactylis glomerata}"
45	"All or most spikelets in an inflorescence with 1 bisexual floret, sometimes with 1–2 sterile or staminate florets below the bisexual floret, the sterile florets sometimes resembling tufts of hair"	46
45	"All or most spikelets in an inflorescence with 2–25 sexual florets, usually all florets bisexual or the distal florets sterile or unisexual, sometimes all florets unisexual, sometimes the plants unisexual"	69
46	"Spikelets with 1–2 staminate or sterile florets below the bisexual floret, sterile florets sometimes knoblike or resembling tufts of hair"	47
46	"Spikelets without staminate or sterile florets below the bisexual florets"	49
47	"Spikelets with 2 florets of similar size, the lower floret staminate; lower lemmas awned, the lemmas of the terminal floret unawned or awned"	"Arrhenatherum {Arrhenatherum elatius}"
47	"Spikelets with 2–3(4) florets, the lower 1–2 florets staminate or sterile, sometimes knoblike or resembling tufts of hair, sometimes larger than the bisexual floret; lemmas of the lower florets awned or unawned, the lemmas of the terminal floret unawned"	48
48	"Lower sterile florets 2, from shorter than to exceeding the bisexual floret; fresh leaves sweet-smelling when crushed"	Anthoxanthum
48	"Lower sterile florets 1–2, varying from knoblike projections on the callus of the bisexual floret to linear or lanceolate lemmas up to 3/4 as long as the bisexual floret; fresh leaves not sweet-smelling when crushed"	Phalaris
49	"Spikelets 15–50 mm long; lemmas usually dorsally awned, awns 20–90 mm long, sometimes unawned"	Avena
49	"Spikelets 1–15 mm long; lemmas unawned or awned, awns to 18 mm long, basal, dorsal, subterminal, or terminal"	50
50	"Glume bases gibbous and subcoriaceous; disarticulation above the glumes"	"Gastridium {Gastridium phleoides}"
50	"Glumes bases not gibbous, usually membranous; disarticulation above or below the glumes"	51
51	"Lemmas awned, awns longer than 2 mm"	52
51	"Lemmas unawned or, if awned, awns shorter than 2 mm"	60
52	"Glumes coriaceous, rigid, hispid or scabrous; lemmas awned, awns 5–14.5 mm long, subterminal"	"Limnodea {Limnodea arkansana}"
52	"Glumes membranous, flexible, glabrous or with soft hairs, usually smooth; lemmas awned, awns 0.5–18 mm long, sometimes subterminal"	53
53	"Disarticulation below the glumes"	54
53	"Disarticulation above the glumes"	56
54	"Spikelets borne on stipes; disarticulation at the base of the stipes; lemmas 0.5–2 mm long; glumes usually awned, sometimes unawned"	Polypogon
54	"Spikelets borne on pedicels; disarticulation immediately below the glumes; lemmas 1.5–7.5 mm long; glumes usually unawned"	55
55	"Paleas absent or greatly reduced; lemma awns attached at midlength or below; glume bases often fused; rachillas not prolonged beyond the floret base"	Alopecurus
55	"Paleas from 3/4 to nearly as long as the lemmas; lemma awns subterminal; glume bases not fused; rachillas usually prolonged beyond the base of the distal floret as a minute stub or slender bristle"	Cinna
56	"Rachillas not prolonged beyond the base of the distal floret; paleas absent, minute, or subequal to the lemmas; lemmas 0.5–4 mm long"	57
56	"Rachillas prolonged beyond the base of the distal floret; paleas at least 1/2 as long as the lemmas; lemmas 1–8 mm long"	58
57	"Lemmas usually glabrous, sometimes pubescent, unawned or awned, if awned, the awns usually shorter than 4.5 mm, sometimes to 10 mm long, basal, dorsal, subterminal, or terminal; veins usually not excurrent, if excurrent, not forming awnlike teeth; panicles often open, sometimes contracted and cylindrical"	Agrostis
57	"Lemmas pilose and dorsally awned, awns 4.5–6 mm long; lateral lemma veins excurrent, forming 4 teeth, teeth sometimes awnlike; panicles dense"	"Bromidium {Bromidium tandilense}"
58	"Plants annual; calluses glabrous or sparsely hairy; lemma apices entire; marginal veins not excurrent; awns subterminal"	Apera
58	"Plants perennial; calluses usually abundantly, sometimes sparsely hairy, hairs 0.2–6.5 mm long; lemma apices denticulate or the marginal veins excurrent; awn attachment from nearly basal to subterminal"	59
59	"Lemma surfaces mostly glabrous; lemma apices denticulate; marginal lemma veins not excurrent"	Calamagrostis
59	"Lemma surfaces hairy; lemma apices erose or toothed; marginal lemma veins excurrent"	"Lachnagrostis {Lachnagrostis filiformis}"
60	"Disarticulation below the glumes"	61
60	"Disarticulation above the glume"	63
61	"Glumes attached to stipes, disarticulation at the base of the stipes; glumes usually awned, awns flexuous"	Polypogon
61	"Glumes attached to pedicels, disarticulation immediately beneath the glumes; glumes unawned or with stiff awns"	62
62	"Lemma awns subterminal; glume bases not fused; paleas from 3/4 to nearly as long as the lemmas; rachillas prolonged beyond the base of the distal floret for 0.1–1.3 mm"	Cinna
62	"Lemma awns attached at midlength or below; glume bases often fused; paleas absent or greatly reduced; rachillas not prolonged beyond the base of the distal floret"	Alopecurus
63	"Glumes 8–15 mm long; plants strongly rhizomatous"	Ammophila
63	"Glumes 1–10 mm long; plants rhizomatous or not"	64
64	"Spikelets dorsally compressed; lemmas dark, coriaceous, lustrous, and glabrous"	Milium
64	"Spikelets laterally compressed, sometimes weakly so; lemmas not simultaneously dark, coriaceous, lustrous, and glabrous"	65
65	"Lower glumes exceeded by the florets, upper glumes exceeded by to exceeding the florets; sheaths usually closed for up to 1/5 their length"	"Arctagrostis {Arctagrostis latifolia}"
65	"Both glumes subequal to or exceeding the florets; sheaths open to the base"	66
66	"Paleas absent or minute to subequal to the lemmas, not veined; rachillas not prolonged beyond the base of the distal florets; lemmas often unawned, sometimes awned, awn attachment basal to terminal"	Agrostis
66	"Paleas more than 1/2 as long as the lemmas, 2-veined; rachillas prolonged beyond the base of the floret by at least 0.1 mm; lemmas often awned, awn attachment usually on the proximal 1/2 of the lemma"	67
67	"Calluses hairy, hairs 0.5–4.5 mm long; lemmas usually awned, awns usually attached to the proximal 1/2, if the attachment higher, the callus hairs longer than 2 mm and/or the awns geniculate"	Calamagrostis
67	"Calluses glabrous or with hairs to about 1 mm long; lemmas unawned or terminally awned, awns to 1(2.2) mm long"	68
68	"Glumes 4–9 mm long; sheaths closed for 1/2–2/3 their length; plants of arctic and subarctic regions"	"Dupontia {Dupontia fisheri}"
68	"Glumes 1.6–4.3 mm long; sheaths open; plants of western North America, from Alaska to California"	Podagrostis
69	"One or both glumes exceeding the adjacent lemmas, sometimes exceeding the distal floret"	70
69	"Both glumes shorter than or subequal to the adjacent lemmas"	92
70	"All lemmas within a spikelet unawned or with awns shorter than 2 mm"	71
70	"One or all lemmas within a spikelet awned, the awns at least 2 mm long"	81
71	"Spikelets usually with 2 florets, lemmas of the lower florets unawned, lemmas of the upper florets awned, the awns strongly curved or hooked"	Holcus
71	"Spikelets with 2–22 florets, all lemmas unawned or if awned, the awns straight"	72
72	"Leaf sheaths closed for at least 1/2 their length; caryopses falling free of the lemma and palea; plants of arctic or subarctic regions"	73
72	"Leaf sheaths open for most of their length; caryopses usually falling with the lemma and palea attached; plants of temperate, arctic, or subarctic regions"	74
73	"Lemma apices obtuse; paleas subequal to the lemmas"	"Arctophila {Arctophila fulva}"
73	"Lemma apices acute to acuminate; paleas shorter than the lemmas"	"Dupontia {Dupontia fisheri}"
74	"Glumes 15–50 mm long; plants annual"	Avena
74	"Glumes 0.4–9 mm long; plants annual or perennia"	75
75	"Lemmas inflated, about as wide as long, with broadly rounded backs; calluses glabrous; spikelets pendulous"	Briza
75	"Lemmas not inflated, longer than wide, keeled to rounded over the midvein; calluses usually with hairs, sometimes glabrous; spikelets not pendulous"	76
76	"Plants annual; spikelets with 2 florets; lemmas evenly hairy, 3-veined"	"Dissanthelium {Dissanthelium californicum}"
76	"Plants usually perennial, sometimes annual; spikelets with 2–10 florets; lemmas usually glabrous or with unevenly distributed hairs, never both annual and with evenly distributed hairs, 3–9-veined"	77
77	"Rachilla internodes hairy, hairs at least 1 mm long"	78
77	"Rachilla internodes glabrous or with hairs shorter than 1 mm on the distal portion"	79
78	"Lemma apices truncate, erose to 2–4-toothed"	Deschampsia
78	"Lemmas apices acute, bifid"	Trisetum
79	"Plants strongly rhizomatous; glumes 5–9 mm long ... Scolochloa"	"Scolochloa {Scolochloa festucacea}"
79	"Plants not or weakly rhizomatous; glumes 0.4–9 mm long"	80
80	"Panicle branches densely pubescent, hairs 0.1–0.2 mm long; lemma apices entire, sometimes mucronate; lemma veins converging distally"	Koeleria
80	"Panicles branches glabrous, sometimes scabrous; lemma apices entire or serrate to erose, not mucronate; lemma veins more or less parallel distally"	Puccinellia
81	"Lemmas 14–40 mm long; glumes 7–11-veined"	Avena
81	"Lemmas 1.3–16 mm long; glumes 1–9-veined"	82
82	"Lemmas 7–16 mm long"	83
82	"Lemmas 1.3–7 mm long"	84
83	"Adaxial surfaces of the leaves ribbed; rachillas pilose on all sides; ligules truncate to rounded, 0.5–1.5 mm long"	Helictotrichon
83	"Adaxial surfaces of the leaves unribbed; rachillas glabrous on the side adjacent to the paleas, hairy elsewhere; ligules acute to truncate, 0.5–7 mm long"	Avenula
84	"Lemmas 1-veined, awned, awns articulated near the middle, the proximal segment yellow-brown to dark brown, the distal segment pale green to whitish, the junction marked by a ring of minute, conical protuberances"	"Corynephorus {Corynephorus canescens}"
84	"Lemmas 3–7-veined, at least some lemmas awned, awns not articulated"	85
85	"Disarticulation below the glumes"	86
85	"Disarticulation above the glumes"	87
86	"Spikelets usually with 2 florets, the lower florets bisexual with unawned lemmas, the upper florets staminate or sterile with awned lemmas"	Holcus
86	"Spikelets with 2–5 florets, all florets bisexual or sometimes the distal florets sterile; all lemmas awned"	Trisetum
87	"Lowest lemma within a spikelet unawned or with a straight awn up to 4 mm long, the distal lemmas within a spikelet always awned, awns 10–16 mm long, geniculate"	"Ventenata {Ventenata dubia}"
87	"All lemmas within a spikelet similarly awned or the awns of the lower lemmas longer than those of the upper lemmas, or the upper lemmas with awns shorter than 10 mm"	88
88	"Callus hairs about 1/2 as long as the lemmas; rachillas not prolonged or prolonged about 0.5 mm or less beyond the base of the distal floret; plants loosely cespitose"	"Vahlodea {Vahlodea atropurpurea}"
88	"Calluses usually glabrous or the hairs much shorter than 1/2 the length of the lemmas, if about 1/2 as long, the rachillas prolonged more than 0.5 mm beyond the base of the distal floret and the plants usually densely cespitose"	89
89	"Plants annual; culms 1–60 cm tall; rachillas not prolonged beyond the base of the distal florets"	Aira
89	"Plants perennial or annual; culms 5–150 cm tall; rachillas prolonged beyond the base of the distal florets, the prolongations hairy"	90
90	"Rachilla internodes glabrous or with hairs shorter than 1 mm on the distal portion; panicle branches densely pubescent, not scabrous"	Koeleria
90	"Rachilla internodes hairy, hairs at least 1 mm long; panicles branches usually glabrous, sometimes scabrous"	91
91	"Lemma apices truncate, erose or 2–4-toothed"	Deschampsia
91	"Lemmas apices acute, bifid"	Trisetum
92	"Upper lemma(s) in a spikelet with hooked or geniculate awns, awns 2–16 mm long; lowest lemmas unawned or terminally awned, awns straight, to 4 mm long"	93
92	"Lemmas all similarly awned or unawned"	94
93	"Spikelets 9–15 mm long, with 2–20 florets; awns of the distal florets 10–16 mm long"	"Ventenata {Ventenata dubia}"
93	"Spikelets 3–7 mm long, with 2 florets; awns of the distal floret 2–5 mm long"	Holcus
94	"Lower lemmas with awns longer than 2 mm"	95
94	"Lower lemmas unawned, mucronate, or with awns up to 2 mm long"	100
95	"Calluses hairy; rachillas prolonged beyond the base of the distal florets"	96
95	"Calluses glabrous or sparsely hairy; rachillas sometimes prolonged beyond the base of the distal floret"	97
96	"Glumes shorter than the adjacent lemmas; ligules 4.5–20 mm long"	Amphibromus
96	"Glumes subequal to the adjacents lemmas; ligules 0.5–6 mm long"	Trisetum
97	"Panicles dense, spikelike; plants annual"	"Rostraria {Rostraria cristata}"
97	"Panicles not both dense and spikelike; plants perennial or annual"	98
98	"Anthers 1; plants annual"	Vulpia
98	"Anthers 3; plants perennial"	99
99	"Leaves without auricles; blades flat, conduplicate, involute, or convolute"	Festuca
99	"Lower leaves with auricles; blades flat"	Schedonorus
100	"Lemmas inflated, about as wide as long; spikelets pendulous"	Briza
100	"Lemmas not inflated, longer than wide; spikelets appressed to divergent, not pendulous"	101
101	"Lemmas apices rounded, truncate, obtuse, or emarginate"	102
101	"Lemma apices acute to acuminate, sometimes mucronate or shortly awn-tipped"	110
102	"Lemmas conspicuously 3-veined; lower glumes 0–3-veined"	103
102	"Lemmas (3)5–9-veined, the veins often inconspicuous; lower glumes 1–5-veined"	104
103	"Lower glumes without veins; lemmas not keeled over the lateral veins"	"Catabrosa {Catabrosa aquatica}"
103	"Lower glumes 1–3-veined; lemmas keeled over each vein"	"Cutandia {Cutandia memphitica}"
104	"Inflorescences usually exceeded by the leaves; lemmas indurate at maturity; pedicels 0.5–0.8 mm thick; culms usually prostrate to procumbent, sometimes ascending; upper glumes 2.6–6.2 mm long ... Sclerochloa (in part)"	"Sclerochloa {Sclerochloa dura}"
104	"Inflorescences exceeding the leaves at maturity; lemmas usually membranous at maturity, sometimes coriaceous; pedicels less than 0.5 mm thick; culms usually erect; upper glumes 0.7–4.5(9) mm long ... (37)"	105
105	"Lower glumes about as long as the upper glumes but no more than 1/2 as wide; disarticulation below the glumes"	Sphenopholis
105	"Lower glumes shorter than the upper glumes or subequal and more than 1/2 as wide; disarticulation above the glumes"	106
106	"Sheaths closed for more than 1/2 their length"	"Arctophila {Arctophila fulva}"
106	"Sheaths open their entire length"	107
107	"Panicle branches stiff; lemmas coriaceous; plants annual; culms to 60 cm tall"	Desmazeria
107	"Panicle branches flexible; lemmas usually mem-branous, sometimes coriaceous; plants usually perennial, sometimes annual or biennial; culms 2–145 cm tall"	108
108	"Lemma veins excurrent, lemma apices indistinctly 3-lobed or toothed; plants strongly rhizomatous, rhizomes succulent"	"Scolochloa {Scolochloa festucacea}"
108	"Lemma veins not excurrent, lemma apices entire, serrate, or erose; plants sometimes rhizomatous, rhizomes not succulent"	109
109	"Lemma veins (5)7–9, prominent; plants of non-saline and non-alkaline habitats"	Torreyochloa
109	"Lemma veins (3)5(7), inconspicuous or prominent; plants of saline and alkaline habitats"	Puccinellia
110	"Lemmas (3)5–9-veined, veins more or less parallel distally, conspicuous"	111
110	"Lemmas 3–9-veined, veins converging distally, usually inconspicuous, sometimes conspicuous"	112
111	"Lemma veins (5)7–9; plants rhizomatous, growing in non-saline and non-alkaline habitats"	Torreyochloa
111	"Lemma veins (3)5(7); plants not truly rhizomatous, sometimes the culms rooting at buried lower nodes, growing in saline and alkaline habitats"	Puccinellia
112	"Lemmas conspicuously 3-veined, keeled over each vein; panicle branches divaricate; plants annual"	"Cutandia {Cutandia memphitica}"
112	"Lemmas inconspicuously (3)5–9-veined, sometimes keeled over the midvein, not over the other veins; panicle branches divaricate or not; plants annual or perennial"	113
113	"Disarticulation below the glumes; lower glumes subequal to the upper glumes but no more than 1/2 as wide"	Sphenopholis
113	"Disarticulation above the glumes, sometimes above the basal floret; lower glumes shorter than the upper glumes or, if subequal, more than 1/2 as wide"	114
114	"Panicle branches smooth, hairy, hairs soft"	Koeleria
114	"Panicle branches smooth or scabrous, glabrous or strigose, never covered with soft hairs"	115
115	"Rachillas pilose, hairs at least 2 mm long"	"Ampelodesmos {Ampelodesmos mauritanicus}"
115	"Rachillas glabrous or with hairs shorter than 1 mm"	116
116	"Basal leaves with auricles"	Schedonorus
116	"No leaves with auricles"	117
117	"Lemma veins parallel distally; plants of saline and alkaline habitats"	Puccinellia
117	"Lemma veins converging distally; plants of many habitats, including saline habitats"	118
118	"Leaf blades with translucent lines on either side of the midvein, apices often prow-tipped; lemmas often with a tuft of hair at the base of the midvein; hila round to oval"	Poa
118	"Leaf blades without translucent lines on either side of the midvein, apices not prow-tipped, often flat; lemmas without a tuft of hair below the midvein hila usually linear, always linear in perennial species"	119
119	"Plants perennial"	120
119	"Plants annual"	121
120	"Plants and florets bisexual; glumes not translucent; caryopses obovoid-oblong"	Festuca
120	"Plants unisexual; glumes translucent; caryopses fusiform"	"Leucopoa {Leucopoa kingii}"
121	"Ligules up to 1 mm long; lemma apices mucronate or awned"	Vulpia
121	"Ligules 1–4 mm long; lemma apices never awned, sometimes mucronate"	122
122	"Panicle branches up to 2 cm long, stiff, spikelet-bearing to the base; culms procumbent to erect"	Desmazeria
122	"Panicles branches 2–10 cm long, flexible, spikelets confined to the distal portion; culms erect"	"Eremopoa {Poa altaica}"