1	"Spikelets with 2 florets, usually falling with the glumes at maturity, the upper floret bisexual and the lower sterile or staminate, often greatly reduced; spikelets usually dorsally compressed, sometimes terete, often in pairs or triplets"	Panicoideae
1	"Spikelets with 1-many florets, breaking up at maturity above the more or less persistent glumes (not breaking up in cultivated cereals) or, if falling with the glumes, not with 2 florets of which the lower is sterile or staminate and the upper bisexual; spikelets usually laterally compressed or terete"	2
2	"Ovaries with a fleshy, hairy apical appendage, the styles arising below it; spikelets longer than 10 mm, always with 2 or more florets"	Pooideae
2	"Ovaries without a fleshy hairy apical appendage; styles terminal; spikelets ofter shorter than 10 mm, often with only 1 floret"	3
3	"Lemmas deeply divided into 5-9 awns or lobes; lemmas hairy below midlength"	Choridoideae
3	"Lemmas entire, bifid, or bilobed, unawned or with 1-3 awns; lemmas glabrous or variously hairy"	4
4	"Spikelets  with only 1 fertile floret, with or without additional sterile florets"	5
4	"Spikelets with 2 or more fertile florets (except Leptochloa rupestris]"	14
5	"Glumes both suppressed; paleas 1-keeled"	Oryzoideae
5	"At least 1 glume, and  often both, well developed; paleas 2-keeled"	6
6	"Spikelets falling with their glumes at maturiy, either singly or in clusters, from the persistent axes of spikelike panicles or spikelke panicle branches, or the axes breaking transversely at the nodes; lemmas delicately 1- to 3-veined"	Chloridoideae
6	"Spikelets breaking up at maturity, the glumes remaining attached"	7
7	"Inflorescences composed of spikelike branches, these solitary, digitate, or racemosely arranged"	Chloridoideae
7	"Inflorescnces paniculate, open, closed, or spikelike"	8
8	"Spikelets with 1 floret"	9
8	"Spikelets with 2 or 3 florets"	12
9	"Lemmas 3-awned"	"Aristidoideae {Aristideae}"
9	"Lemmas 1-awned or unawned"	10
10	"Lemmas hardened at maturity, awned from the top"	Pooideae
10	"Lemmas hyaline or membranous at maturity"	11
11	"Lemmas usually awned; glumes longer and firmer than the hyaline lemmas; pericarps adhering to the seeds even when wer"	Pooideae
11	"Lemmas unawned; glumes and lemmas similar in texture; glumes often shorter than the lemmas; pericarps easily separated from the seeds when wet"	Chloridoideae
12	"Spikelets with 2 florets, the lower sterile or staminate, the upper bisexual"	Panicoideae
12	"Spikelets with 3 florets, the lower 2 represented by sterile lemmas"	13
13	"Sterile lemmas coriaceous, at least the upper exceeding the fertile floret and transversely wrinkled"	Oryzoideae
13	"Sterile lemmas subulate, both shorter than the fertile lemma"	Pooideae
14	"Plants (1-)1.5-6 m or more tall; culms erect, usually at least 8 mm in diameter at the base; inflorescences plumose panicles 20-60 cm long"	"Arundinoideae {Arundineae}"
14	"Plants usually shorter than 1.5 m tall; culms decumbent to erect, less than 8 mm in diameter at the base; inflorescences not plumose, usually shorter than 20 cm"	15
15	"Inflorescences usually composed of spikelike branches, these solitary, digitate, or racemosely arranged, sometimes forming dense, ovoid heads, if open panicles, lemmas 3-veined"	Chloridoideae
15	"Inflorescences usually open panicles, rarely of spikelike branches but, if so, lemmas tuberculate; lemmas 5-7-veined"	Pooideae