FLOWERING PLANTS AND FERNS OF ARIZONA 109 



1. Holcus lanatus L., Sp. PL 1048. 1753. 



Flagstaff (Coconino County), about 7.000 feet, meadows and moist 

 places. Widely distributed in North America, introduced from 

 Europe. 



Occasionally cultivated in meadows in the eastern United States. 

 It is reported that the plant, either fresh or wilted, sometimes develops 

 hydrocyanic acid. 



31. DANTHONIA. Oatgrass 



Tufted perennial with small open panicles of rather large spikelets; 

 spikelets several-flowered; glumes equal, broad, papery, exceeding 

 the florets; lemma rounded on the back, bifid, the lobes acute, with 

 a stout, flat, twisted, geniculate awn from between the lobes. 



1. Danthonia intermedia Vasey, Torrey Bot. Club Bui. 10: 52. 1883. 

 White ]\ Fountains. Apache County {Griffiths 5350). Wet meadows 

 in northern or alpine regions. Quebec to Alaska, south to Michigan, 

 Xew Mexico, Arizona, and California. 



32. CALAMAGROSTIS. Reedgrass 



Erect, rhizomatous perennials with firm, flat or loosely involute 

 leaf blades and spikelike or narrow and open panicles; glumes equal, 

 acute or acuminate; rachilla prolonged beyond the floret, hairy; 

 lemma shorter than the glumes, the callus bearded, the midnerve 

 exserted as an awn. 



Several species of this genus are important forage grasses in other 

 regions. Bluejoint reedgrass (C. canadensis) is a source of much of 

 the wild hay in Wisconsin and Minnesota. In some parts of the 

 United States, northern reedgrass (C. inexpansa) is grazed by horses 

 and cattle. 



Key to the species 



1. Panicle nodding, rather loose and open; callus hairs copious, about as long as 

 the lemma 1. C. canadensis. 



1. Panicle erect, dense or spikelike (2). 



2. Leaf blades flat: glumes 4 to 6 mm. long; panicle moderately dense. 



2. C. SCOPULORFM. 



2. Leaf blades involute: glumes 3 to 4 mm. lone;: panicle spikelike, more or less 

 interrupted below; culms scabrous belcnv the inflorescence. 



3. C. iXExrAX>A. 



1. Calamagrostis canadensis (Michx.) Beauv., Ess. Agrost. 15, 152, 



157. 1812. 



Arundo canadensis Michx., Fl. Bor. Amer. 1: 73. 1803. 



Kaibab Plateau (Coconino County), Pinaleno Mountains (Graham 

 County). Rincon Mountains (Pima County), 7.400 to 9.500 feet, 

 wet places and open woods. Greenland to Alaska, south to North 

 Carolina, Kansas, Xew Mexico, Arizona, and California. 



2. Calamagrostis scopulorum M. E. Jones. Calif. Acad. Sei. Proc- 



ser. 2, 5: 722. 1895. 

 Kaibab Trail to Roaring Springs. Grand Canyon. Coconino County 

 (Eastwood and Howell 7075). Moist soil. Wyoming. Colorado, Utah, 

 Xew Mexico, and Arizona. 



