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Poaceae Group 5
See list of 18 genera in this group-
1a. Lemmas with 2, 3, or 5 conspicuous lobes or teeth at the apex
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2a. Lemmas 3- or 5-lobed at the apex and with 3 awns; spikelets not sunken into cavities of the inflorescence rachis; inflorescence a panicle consisting of an axis and spike-like branches; disarticulation occurring at the base of the short, spike-like branches, these falling from the panicle axis (in part)
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2b. Lemmas with 2 or 3 tooth-like lobes at the apex, usually only 1 of these prolonged into an evident awn (note: the awns usually longest on spikelets in the apical portion of the inflorescence); spikelets appearing sunken into obvious cavities in the thickened rachis; inflorescence a cylindrical spike; disarticulation at the nodes of the spike
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1b. Lemmas entire or inconspicuously bilobed at the apex
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3a. Inflorescence a solitary spike or raceme, the spikelets produced from nodes that alternate of each side of the rachis [Figs. 224,239]
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4a. All but the uppermost spikelets borne on short pedicels (i.e., the inflorescence a raceme)
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5a. Spikelets solitary at each node of the inflorescence [Fig. 239]
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6a. Spikelets arranged with the narrow side toward the rachis; only the glume away from the rachis developed, the other obsolete
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6b. Spikelets arranged with the broad side toward the rachis; both glumes developed
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7a. Plants annual, short persisting crop species; glumes 1- or 3-veined
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8a. Glumes with 1 vein, linear-subulate; keel of lemmas ciliate
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8b. Glumes with 3 veins, ovate; keel of lemmas glabrous
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7b. Plants perennial, native or introduced species; glumes 5- or 7-veined
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9a. Spikelets crowded on short internodes 0.5–2 (–3) mm long, ascending to spreading
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9b. Spikelets less crowded, at least the lower internodes mostly longer than 4 mm, appressed to appressed-ascending
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10a. Glumes gradually tapering from near midlength and ± imperceptively passing into a short awn-tip
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10b. Glumes tapering from the apical third, unawned or somewhat abruptly tapering to an awn
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11a. Glumes acute at the apex, unawned or merely with a tiny mucro up to 0.5 (–0.7) mm long [Fig. 278]
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11b. Glumes long-acute at the apex, usually with an awn 0.5–4 mm long (in part)
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12a. Spikelets consistently 3 at each node, the outer pair usually pedicellate and staminate or sterile (in part)
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12b. Spikelets 2–4 at each node, commonly 2, all bisexual and fertile
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13a. Plants annual; lemmas with awns 50–100 cm long
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13b. Plants cespitose or rhizomatous perennials; lemmas awnless or with awns up to 40 mm long
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14a. Plants mostly self-pollinating, with small anthers 1–3 mm long, cespitose, lacking rhizomes or with short rhizomes; lemmas mostly awned (in part)
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14b. Plants mostly outcrossing, with large anthers mostly 4–9 mm long, not cespitose, with elongate, stout rhizomes; lemmas mostly without awns
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3b. Inflorescence a panicle with 2 or more secund, spike-like branches [Fig. 205]
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15a. Panicle with branches digitately arranged (i.e., all or nearly all originating from the same point) [Fig. 205] or with branches in 1–3 closely spaced whorls
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16a. Rachis of branches extending beyond distal most flowers 1–5 mm; upper glume with an awn 1–2.5 mm long
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16b. Rachis of branches ending in a functional or rudimentary spikelet, not extending as a bristle-tip; glumes unawned or the upper one with a short awn to 0.3 mm
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17a. Lemmas awned, pubescent on the marginal veins and callus; spikelets with 2 or 3 (–5) florets
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17b. Lemmas unawned, glabrous; spikelets with 5–7 florets
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15b. Panicle with branches racemosely arranged along an elongate axis
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18a. Spikelets nearly circular in outline, with 1 or 2 florets, the upper, when present, sterile; glumes obovate, cross-wrinkled, the tips crossing (in part)
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18b. Spikelets not circular in outline, either clearly longer than wide or ± obovate, with 2–20 bisexual florets; glumes linear to elliptic to ovate, not cross-winkled, the tips separate
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Each photo represents one genus in this subgroup.