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I. POEAE (FESTUCEAE) 



A. Plants large, coarse reeds, 2-6 m tall; inflorescence plume-like; rachis 

 bearded with long silky hairs equaling or exceeding lemmas ...15. Phragmites 

 A. Plants less robust, seldom exceeding 1.5 m tall; inflorescence various; rachis 

 lacking beard or if bearded then hairs short 

 B. Spikelets in dense spike-like panicles 



C. Panicles appearing 1-sided; spikelets crowded into asymmetrical 



clusters, somewhat flattened laterally 9. Dactylis 



C. Panicles more or less symmetrical; spikelets not in densely crowded 

 clusters, symmetrical 



D. -Spikelets 8-16-flowered, all fertile; saltmarshes .... 14. Distichlis 

 D. Spikelets 2-3-flowered, terminal spikelets fertile, lower ones 



sterile; old fields 13. Cynosums 



B. Spikelets in more open panicles, sometimes contracted but not 

 spike-like 

 E. Lemmas 2-toothed or 2-lobed at apex 



F. Nodes densely bearded; mature culms readily breaking at node 



12. Triplasis 



F. Nodes glabrous; mature culms not readily breaking 



G. Nerves of lemmas heavily bearded with long divergent 



hairs; leaf sheaths open 11. Tridens 



G. Nerves of lemmas glabrous or at least not bearded with 

 long hairs; leaf sheaths closed 



H. Awns of lemmas divergent 2. Schizachne 



H. Awns of lemmas straight or lacking 1. Bromus 



E. Lemmas entire at apex 

 L Lemmas 3-nerved 



J. Glumes and lemmas green and herbaceous; ligule a 



membranous scale 7. Poa 



J. Glumes and lemmas thin and dry, pale to red; ligule a 



fringe of hairs 10. Eragrostis 



I. Lemmas 5- or more nerved 



K. Spikelets nearly as broad as long, or broader; lemmas with 



broad scarious margins 8. Briza 



K. Spikelets longer than broad; lemmas lacking broad 

 scarious margins 



L. Lemmas keeled with a prominent dorsal ridge..?. Poa 

 L. Lemmas rounded on back, if keeled only at tip 



M. Lemmas with lateral nerves arched, converging at 

 the midrib; mostly awned 



N. Annuals 4. Vulpia 



N, Perennials 3. Festuca 



M. Lemmas with lateral nerves nearly straight; 

 awnless 

 O. Leaf sheaths open; culms slender, weak and 



decumbent or prostrate 5. Puccinellia 



O. Leaf sheaths closed; culms stout, erect 



6. Glyceria 



