6 BULLETIN 545, U. S. DEPAKTMENT OF AGRICULTURE. 



Hordeae. 



A , Spikelets solitary at each joint of the rachis Genus Agropyron* 



A. Spikelets 2 or more at each joint of the rachis. 



B. Rachis continuous, awns erect, not over 2 cm. (f of an inch) long. 



Genus Elymus. 



B. Rachis readily separated into joints, awns spreading, 4 rm. (If inches) or more 

 long Genus Sitanion . 



MOUNTAIN BUNCH GRASS. 

 (Festuca viridula.} 



The genus Festuca is well represented in the United States, about 

 30 native species being recognized. 1 Most of them are abundant in 

 the regions to which they are adapted, though three species have 

 been collected but once, two others but twice, and another species, 

 F. rigescens, has been found but once in North America. 



Several North American species of Fesiuca are of great value for 

 forage and hay. Among these, mountain bunch grass, while not as 

 widely distributed as some others, for example, blue bunch grass 

 (F. idahoensis), is nevertheless the most valuable for grazing pur- 

 poses because of its greater palatability and nutritiousness. Next 

 hi forage value are blue bunch grass (F. idahoensis) and red fescue 

 (F. rubra), of the West, and F. altaica, an important range plant in 

 Alaska. A number of the annuals are valuable for grazing purposes 

 in the semiarid regions, especially in the foothill areas of the South- 

 west, where the seed germinates late in the f^ll and growth contin- 

 ues through the winter. Under such conditions they often furnish 

 a first-class palatable forage at a time when nothing else is available. 



While mountain bunch grass is usually abundant in the localities 

 in which it occurs, it has not a very wide distribution. Its natural 

 home is in the Hudsonian zone, where it occurs from the lower to 

 the higher limits, reaching well up to timber line. Wherever found 

 in the United States it is closely restricted to the higher elevations. 

 On the Wallowa National Forest in northeastern Oregon, it is seldom 

 found below 6,500 feet. Of all the specimens examined in the Na- 

 tional Herbarium the lowest altitude reported was 5,000 feet. 



While stockmen usually recognize the species when they see it, 

 and appreciate its forage value, it is sometimes confused with other 

 grasses, perhaps most commonly with blue bunch grass (F. idahoensis} . 

 The latter, however, is distinctly a plant of the Transition zone and 

 is seldom found where mountain bunch grass abounds. The rather 

 prominent awns and the "bloom" on the leaves, which gives the 

 characteristic bluish tinge, readily distinguish blue bunch grass from 

 F. viridula. 



i Piper, Contr. I'. S. Nat. Herb., Vol. 10, p. 1, 1906. 



