CHAPTER XXIII 

 Tribe XL FESTUCE^ 



A LARGE tribe of about 80 genera, mainly inhabitants 

 of the cooler regions. Spikelets more than 1-flowered, 

 usually several-flowered; inflorescence an open, narrow 

 or sometimes spike-like panicle. If the lemmas are awned, 

 the awn is straight and terminal or rarely from between 

 the teeth of a bifid apex (some species of Bromus and a few 

 species of Festuca). The lemma is divided into several 

 awns at the summit in Pappophorum and Cottea and a 

 few other genera. In some species of Eragrostis the palea 

 is persistent on the inarticulate rachilla. In most of the 

 genera the spikelet breaks up at maturity, each floret 

 falling with a joint of the rachilla, the glumes being 

 persistent on the pedicel. Scleropogon, Monanthochloe, 

 Distichlis and a few species of Poa are dioecious. The 

 blades are broad and petioled in a few tropical genera. 

 Gynerium, Cortaderia, Arundo and Phragmites are 

 tall reeds. 



Key to the Genera of Festuce^ 



A. Lemmas divided at summit into 3 to several 

 awns or awn-like lobes (only the pistillate in 

 Scleropogon; lemmas more or less 3-toothed 

 in Tridens of the next division). 

 B. Awns 9 or more. 



c. Divisions of lemma awn-like, plumose; 



panicle spike-hke. Arizona Pappophorum. 



cc. Divisions membranaceous, awn-pointed; 



panicle open. Texas to Arizona Cottea. 



BB. Awns less than 9. 



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