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Key to Poaceae, Key G: wheat grasses of tribe Triticeae (and a few unrelated mimics)

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1 Spikelets 2-7 at all or most nodes; [tribe Triticeae].
  2 Spikelets 2-5 at each node (if 3, all 3 sessile).
  2 Spikelets 3 at each node (the central spikelets usually sessile, the lateral pedicellate)
1 Spikelets 1 at all or most nodes (occasionally in pairs at lowest nodes).
    3 Spikelets borne on peduncles 0.5-2 mm long; [tribe Brachypodieae]
    3 Spikelets sessile.
      4 Spikelets (not including the awns) > 3× as long as the rachis internodes, strongly divergent (at nearly 90° to the rachis); [very rare exotic]; [tribe Triticeae]
      4 Spikelets (not including the awns) < 3× as long as the rachis internodes.
        5 Glumes subulate to narrowly lanceolate or linear, narrowing from below midlength, with 1 vein throughout or at least distally (sometimes 1-3 veins at midlength in Pascopyrum); [tribe Triticeae]
          6 Awns long, 12-26 (-35) mm; glumes keeled; spikelets with 2 (-3) florets
          6 Awns short, 5 mm or less in length; glumes not keeled; spikelets with 2-12 florets
        5 Glumes broader, narrowing from beyond midlength, with 3-9 veins at midlength.
             7 Spikelets placed edgewise to the rachis; first glume lacking except in the terminal spikelet; [tribe Poeae]
             7 Spikelets placed flatwise to the rachis; first glume present; [tribe Triticeae].
               8 Plants annuals; glumes often with lateral teeth or awns; glumes rounded or keeled; [exotics, rare out of cultivation].
                 9 Glumes rounded; spikelets in some species embedded into the thickened rachis
                 9 Glumes keeled; spikelets never embedded in a thickened rachis
               8 Plants perennials; glumes without lateral teeth or awns; glumes keeled; [natives or exotics].
                   10 Glumes acute to acuminate (and often awned); [common natives and exotics]
                   10 Glumes truncate, obtuse, or acute; [rare exotics]

Key to Poaceae, Key N: grasses with 2+ florets, these readily visible by extending past the glumes

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1 Plants dioecious; plants strongly rhizomatous-clonal; [plants of saline situations, coastal or more rarely inland]; [tribe Cynodonteae; subtribe Monanthochloinae]
1 Plants bisexual; plants cespitose or weakly short- rhizomatous; [plants of various habitats, including saline].
  2 Lemmas 1-3-nerved, the nerves strong and obvious; spikelets 1-27 mm long.
    3 Lemma nerves hairy; lemmas slightly to strongly 2-lobed, the midnerve shortly excurrent between the 2 lobes; [tribe Cynodonteae; subtribe Tridentinae].
      4 Palea glabrous or with hairs < 0.5 mm long; plants perennial; inflorescences exserted, conspicuous
      4 Palea long-ciliate on the upper half, the hairs 0.5-2 mm long; plants annual; inflorescences often largely hidden in the upper sheath
    3 Lemma nerves glabrous; lemmas not at all lobed.
        5 Mature spikelets stiff; grains protruding, with a bottle-neck-like beak; [tribe Diarrheneae]
        5 Mature spikelets not stiff; grains neither protruding, nor shaped with a bottleneck-like beak.
          6 Inflorescence branches usually strongly ascendant (sometimes weakly spreading); culms often disarticulating at the first node; [tribe Arundineae]
          6 Inflorescence branches ascending, widely divergent, or nodding; culms not disarticulating at the first node; [collectively widespread, dry to wet sites]
             7 Florets 3-34 per spikelet; lemmas unawned; [tribe Eragrostideae; subtribe Eragrostidinae]
             7 Florets 2-3 per spikelet; lemmas awned or unawned; [tribe Poeae]
  2 Lemmas 5-many-nerved, the nerves often obscure; spikelets 2-70 mm long.
               8 Sheaths united for at least ½ their length.
                 9 Spikelets in dense one-sided clusters on a few stiff branches; spikelets strongly flattened; [tribe Poeae]
                 9 Spikelets in open or somewhat congested panicles, not as above; spikelets slightly to not at all flattened.
                   10 Lemmas awned.
                     11 Callus of the lemma glabrous; [collectively widespread]; [tribe Bromeae]
                     11 Callus of the lemma pubescent; [of VA, WV, KY, and northward]; [tribe Meliceae]
                   10 Lemmas unawned.
                       12 Lower glumes 1-veined; [plants of wetlands]
                       12 Lower glumes 3-7-veined; [plants of mesic to dry habitats]
               8 Sheaths completely free or united at most up to ½ their length.
                          13 Basal 1-8 florets of the spikelet sterile.
                            14 Ligule membranous (the membrane apex ciliate); lower 1-4 florets sterile; disarticulation above the glumes and between the florets; [of various, usually moist, habitats, collectively widespread]; [tribe Centotheceae]
                            14 Ligule of hairs; lower 2-8 florets sterile; disarticulation below the glumes (the spikelet falling whole); [of coastal dunes, from se. VA southward and westward]; [tribe Eragrostideae; subtribe Uniolinae]
                          13 Lowermost florets of the spikelet fertile; [tribe Poeae].
                              15 Lemmas about as broad as long, spreading at a ca. 90° angle to the rachilla
                              15 Lemmas longer than broad, ascending at an acute angle to the rachilla.
                                16 Lemmas rounded at the apex, not awned.
                                  17 Inflorescence pedicels 0.5-3 mm thick; panicle branches stiff; lemmas coriaceous at maturity
                                  17 Inflorescence pedicels to 0.5 mm thick (if to 0.8 mm as in Sclerochloa dura then culms usually prostrate and leaves also exceeding inflorescence length); panicle branches flexible; lemmas hardened or membranous but not coriaceous at maturity.
                                    18 Inflorescences usually exceeded by the leaves (or sometimes similar in length); culms usually prostrate or procumbent (occasionally ascending); plants often compact and low-growing; mature lemmas hardened
                                    18 Inflorescences exceeding the leaves; culms usually erect; plants compact or not; mature lemmas membranous
                                       19 Lemmas obscurely (3-) 5 (-7) nerved; spikelets 2.5-13 mm long; [habitats usually saline or alkaline]
                                       19 Lemmas prominently 5-9-nerved; spikelets 3.6-6.5 mm long; [habitats non-saline]
                                16 Lemmas acute at the apex, or awned.
                                         20 Callus of the lemmas hairy
 Poa
                                         20 Callus of the lemma glabrous.
                                           21 Lemmas awned.
                                             22 Plant annual; stamen 1
                                             22 Plant perennial; stamens 3.
                                               23 Leaf blades often involute, 0.2-3 mm wide, not auriculate at the base
                                           21 Lemmas unawned.
                                                 24 Leaf tips blunt, cupped like the prow of a row-boat
 Poa
                                                 24 Leaf tips acuminate, planar or keeled (but not as above).
                                                    25 Leaf blades often involute, 0.2-3 mm wide, or flat and 3-12 mm wide, not auriculate at the base
                                                    25 Leaf blades flat, 3-12 mm wide, auriculate at the base