What’s a dichotomous key?
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  - Group 1Lycophytes, Monilophytes
 - Group 2Gymnosperms
 - Group 3Monocots
 - Group 4Woody angiosperms with opposite or whorled leaves
 - Group 5Woody angiosperms with alternate leaves
 - Group 6Herbaceous angiosperms with inferior ovaries
 - Group 7Herbaceous angiosperms with superior ovaries and zygomorphic flowers
 - Group 8Herbaceous angiosperms with superior ovaries, actinomorphic flowers, and 2 or more distinct carpels
 - Group 9Herbaceous angiosperms with superior ovaries, actinomorphic flowers, connate petals, and a solitary carpel or 2 or more connate carpels
 - Group 10Herbaceous angiosperms with superior ovaries, actinomorphic flowers, distinct petals or the petals lacking, and 2 or more connate carpels
 
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 - Dichotomous Key
 - Poaceae
 
Poaceae
See list of 103 genera in this familyHesperostipa comata (Trin. & Rupr.) Barkworth was reported from RI by George (1997), but specimens are unknown.
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      4a. Spikelets dimorphic with the 2 types paired—the lower spikelet of the pair sterile, flabellate, consisting of 2 glumes and several narrow, acuminate lemmas, concealing the upper, fertile spikelets with 2–4 florets
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      4b. Spikelets of a single plant monomorphic
 
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      2b. Spikelets with only 1 evident floret (members of the subfamily Panicoideae key under this lead) [Figs. 181,269,273]
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      6a. Glumes or lemmas or both folded (i.e., V-shaped in cross-section), sometimes with a low to pronounced keel
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      6b. Glumes and lemmas flat, arched, or rounded over the abaxial surface, lacking a keel
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      8b. Inflorescence a congested to open panicle with visible branching, or composed of 2 or more spikes, racemes, or rames
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      9a. Glumes often as long as or longer than the lemmas and concealing the florets; spikelets usually arranged in obvious pairs or triplets with 1 spikelet sessile or shortly pedicellate and the remaining pedicellate (sometimes the pedicellate spikelet reduced and represented by only a pedicel; not organized in pairs or triplets in Milium) [Fig. 240]
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      9b. One (i.e., the lower) or both glumes shorter than the lemmas or the glumes absent; spikelets not organized in pairs or triplets (sometimes in groups of 2 or 3 in Digitaria and Paspalum) [Fig. 269]
 
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   Show photos of:  
  
    Each photo represents one genus in this family.