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Poaceae Group 9
See list of 10 genera in this group-
1a. Spikelets not organized into pairs or triplets, all pedicellate in an open panicle; disarticulation above the glumes, the falling floret leaving the glumes behind
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1b. Spikelets organized into pairs or triplets, some sessile (all pedicellate in Miscanthus, but that genus with glumes subtended by a ring of long, silky hairs); disarticulation below the glumes or between the rame segments, in either case the spikelets falling intact
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2a. Spikelets unisexual, with the carpellate inflorescences or carpellate portion of inflorescence borne below the staminate ones or staminate portions [Fig. 280]
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2b. At least the lower spikelet of each pair or triplet bisexual
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3a. Reproductive stems decumbent, creeping over the ground or other low vegetation; spikelets solitary at each node, the pediceled spikelet absent, represented only a pedicel up to 3 (–4) mm long
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3b. Reproductive stems ascending to erect, not creeping; spikelets solitary, paired, or in trios at each node, when solitary, with a pedicel usually longer than 3 mm
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4a. Spikelets in homogamous and homomorphic pairs (i.e., both spikelets of a pair of similar sex and similar morphology, respectively) [Fig. 240]
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5a. Spikelets in sessile-pedicellate pairs (i.e., one spikelet of a pair sessile, the other borne on a short pedicel) [Fig. 240]; terminal inflorescence of (1–) 2–4 (–6) branches originating from the summit of the peduncle, without or with a very short rachis less than 4 cm long
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5b. Spikelets in unequal-pedicellate pairs (i.e., both spikelets of a pair pedicellate, but 1 spikelet on a shorter pedicel than the other); terminal inflorescence usually with more than 15 branches distributed along a rachis 4–15 cm long
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4b. Spikelets in heterogamous and heteromorphic pairs or trios (i.e., spikelets of a pair or trio not of similar sex nor of similar morphology, respectively)
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6a. Fully formed spikelet solitary at each node, the pedicelled spikelet represented by only its pedicel
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7a. Sessile spikelet lacking an awn; pedicels and rame internodes glabrous; mat-forming, stoloniferous plants with reproductive stems 10–35 cm tall (in part)
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7b. Sessile spikelet with an awn; pedicels and rame internodes pubescent; cespitose or rhizomatous plants with reproductive stems 40–300 cm tall
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8a. Pedicels and rame internodes pubescent with white hairs [Fig. 186]; glumes glabrous or scaberulous; peduncles subtended by, or even partly included in, a modified, shortened leaf (in part)
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8b. Pedicels and rame internodes pubescent with yellow-brown hairs; lower glume hirsute; peduncles not closely subtended by a modified leaf
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6b. Spikelets paired or in trios at each node, with 1 or 2 pedicelled spikelets, these usually smaller than the sessile spikelet
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9a. Each inflorescence peduncle supporting a solitary rame (though each plant may have many peduncles)
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10a. Inflorescence solitary and terminal; pedicels and rame internodes glabrous; reproductive stems 10–35 cm tall (in part)
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10b. Inflorescences both terminal and axillary; pedicels and rame internodes pubescent; reproductive stems 30–210 cm tall
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9b. Each inflorescence peduncle supporting 2 or more rames or branches
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11a. Inflorescence a panicle with compound branches distributed along an elongate axis, the ultimate branches of the panicle being rames; pedicel of pedicellate spikelet 1–3.3 mm long
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11b. Inflorescence composed of simple, digitately arranged rames, lacking an elongate central axis; pedicel of pedicellate spikelet (2.7–) 3–5.8 mm long (in part)
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Each photo represents one genus in this subgroup.