59 



approacberl, however, changes in the grass flora become apparent. 

 The gramas and wheat-grasses of the plains are replaced by "bmich- 

 grasses" of various kinds, sheep fescue {Festuca oi'ina), and mountain 

 wheat-grass [Agropyron violaceum)', brome-grasses become more abun- 

 dant: the common needle-grass, porcuijiue-grass and feather bunch- 

 grass give way to Tweedy's needle-grass {Stipa tweedy i), IS^elson's 

 needle-grass {8. nelsoni), and 

 purple-top needle-grass {S. 

 minor); wild oat-grasses, 

 meadow or spear- grasses, and 

 tussock- grass become plenti- 

 ful; and mountain blue joint 

 takes the place of common 

 blue joint and yellow-top. 



In the dry soils of the 

 higher foothills and moun- 

 tains the most important pas- 

 ture grasses are the "bunch 

 grasses" and the oat-grasses. 

 The former term is a very gen- 

 eral one, and as used on the 

 range includes a great many 

 different kinds of grasses. 

 For example, in Colorado 

 "bunch-grass" probably 

 most often means one of the 

 fescues [Festuca scabrella), 

 more properly called buft'alo 

 bunch- grass; in Wyoming 

 and Montana the term is 

 probably most often applied 

 to the three Ports mentioned 

 under the discussion of mea- 

 dow-grasses, but is also often 

 applied to certain of the 

 fescues, as sheep fescue — 

 often also called "deer 



grass" — and King's fescue [Festuca Mngii) (see fig. 23), the northern 

 representative of buffalo bunch-grass. Some of the wheat grasses 

 [Agropyron dfvergens and A. vaseyi) are also "bunch-grasses," but 

 as a rule some modification of the term is used in designating them, 

 as wire bunch-grass or bunch wheat- grass. All the above-mentioned 

 grasses are valuable as forage producers and are widely distributed, 

 most of them occurring over all or at least a large portion of the east- 

 ern Kocky Mountain region. In the higher altitudes sheep fescue, 

 the bunch-grass Poa-s-, and the wild-oat-grasses furnish most of the 



Fig. 23.— King's fescue (Festuca kingii). 



