RANGE FEED. 47 



winter precipitation occurs, what is left of them is quite well l)leached 

 out. The value of grass for winter feeding alwa3's depends upon its 

 beino- drv cured. When the winter rains come, therefore, stock begin 

 to shun the old grass in proportion as the succulent annual stutf 

 develops. During this cold winter and spring moist season there are, 

 however, a few g-rasses which are of some importance in the forage 

 ration upon the range. The most iiuportant of these are BroiiiHS car- 

 Indtns^ Pod h>/i(j!j»'(h(ncul((t((, P. ftndUi'uina^ P. higelovn^ and Festuca 

 (x'tojjord. Occasionally, however, the winter rains are prolonged into 

 the warm spring season sufficientl}' to allow the perennial grasses, of 

 which the gramas upon the open foothills are the most' important, to 

 get a start. In such a season there is some good feed produced by 

 these in the spring, but this condition is an exceptional one, and we 

 may say that as a general rule the perennial grasses which furnish 

 the feed of midsummer to winter season do not grow at all in the 

 spring. There is aliundant evidence, however, that they would fur- 

 nish two crops if the moisture and temperature conditions were 

 favorable. 



The most important of the grasses belong to the group known 

 popularly as gramas {Boateloua spp.), some of which are perennial 

 and some annual. The perennials grow in the higher altitudes, and 

 are mainl}^ Botdeloua oJlgostachya^ B. CHrt'rpenduhi^ B. hromoideK, B. 

 ro'krocHi, B. hirsuta, B. eriopoda, and />. haiyfrdt/', with consider- 

 able areas of B. trifidn upon some stony, bare, high foothills. These 

 furnish the best and most important range feed. Bontthud rofJirockii 

 extends to lower altitudes than the others, and at tunes is strictly a 

 mesa plant, furnishing upon favorable places and in favorable seasons 

 a thin stand of large bunches. It is in the open foothills, however, 

 that this species reaches its best development. Here, together with 

 other species of lesser importance, it often makes sufficient growth for 

 hay. The open foothills of the Whetstone, Huachuca, Santa Rita, and 

 Babucjuivari mountains, the Sulphur Spring Valley, and the high 

 mesas between the Santa Catalina and Willow Spring mountains fur- 

 nish extensive areas of this grass in favorable seasons. It is interesting 

 to compare this distribution with similai" situations in the Mesilla Val- 

 ley of New Mexico, where Professor Wooton states that Boutelbua 

 eriopoda^ which is never an exclusive crop in southern Arizona, is 

 often cut for ha'v. All of these species occur in the southern part of 

 Arizona, but it is the blue grama [Bouteloua oUgostachya) that is of the 

 greatest importance in the northern part. Here it is by far the most 

 important grass upon the high plateau surrounding the San Francisco 

 and contiguous divides. Many of the juniper ridges so characteristic 

 here have practically no other grass, and even this makes only a thin, 

 short growth very different from its habit in the southern part of the 

 Territor}^ w^here it assumes a more erect and robust character. The 

 4416— No. 67—04 4 



