108 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



1. Deschampsia danthonioides (Trin.) Munro in Benth., PI. Hartw. 



342. 1857. 



Aim danthonioides Trin., Acad. St. Petersb. Mem. VI Math. 

 Phys. Nat. 1: 57. 1830. 



Arizona, without definite locality (Lemmon 386 in 1882). Dry or 

 moist open ground, Alaska to Montana, south to Arizona and Baja 

 California; Texas; Chile. 



2. Deschampsia elongata (Hook.) Munro in Benth., PI. Hartw. 342. 



1857. 



Aim elongata Hook., Fl. Bor. Amer. 2: 243. 1840. 



Pinaleno Mountains (Graham County), Santa Catalina Mountains 

 (Pima County), about 7,500 to 9,100 feet, moist or dry open ground. 

 Alaska to Wyoming, Arizona, California, and Mexico. 



3. Deschampsia caespitosa (L.) Beauv., Ess. Agrost. 91, 149, 160. 



1812. 



Aira caespitosa L., Sp. PI. 64. 1753. 



Apache, Coconino, and Cochise Counties, up to 9,500 feet, damp or 

 wet mountain meadows, June to September. Greenland to Alaska, 

 south to North Carolina, Illinois, North Dakota, New Mexico, 

 Arizona, and California; also in the Old World. 



This species affords excellent forage in mountain meadows. 



29. AVENA. Oat 



Annuals with relatively broad leaf blades and open panicles of large 

 spikelets; spikelets 2- or 3-flowered; rachilla villous; glumes equal, 

 several-nerved, exceeding the florets; lemmas indurate, bidentate, 

 hairy, bearing a dorsal bent or twisted awn. 



The wild oats are often troublesome weeds but occasionally are 

 useful for hay and pasturage. The long-awned fruits are injurious to 

 the mouths of animals. The commonly cultivated oat is Avena 

 sativa L. 



Key to the species 



1. Teeth of the lemma acute; pedicels rather stout 1. A. fatua. 



1. Teeth of the lemma setaceous; pedicels curved, capillary 2. A. barbata. 



1. Avena fatua L., Sp. PI. 80. 1753. 



Apache, Gila, Pinal, Cochise, and Pima Counties, in waste places. 

 Maine 'to Pennsylvania, Missouri, South Dakota, New Mexico, 

 Arizona, and California; introduced from Europe. 



2. Avena barbata Brot., Fl. Lusit. 1: 108. 1804. 



Tucson, Pima County (Tourney 747). A weed in waste places, 

 Washington to California and Arizona. 



30. HOLCUS. Velvet grass 



Tufted perennial with flat, velvety-pubescent leaf blades and com- 

 pact panicles; spikelets 2-flowered, the pedicel disarticulating below 

 the glumes; glumes nearly equal, longer than the florets; first floret 

 perfect, the lemma awnless ; second floret staminate, the lemma bearing 

 a short recurved awn from the back near the apex. 



