ROOTS, TUBERS, AND OTHER SUCCULENT FEEDS 145 



Range and Desert Plants. The common plants growing in 

 trie deserts and mountain ranges of western United States are sage 

 brush, greasewood and species of salt bush (Atriplex). These plants 

 are able to grow in the regions mentioned because of their ability to 

 withstand extreme drought and a considerable amount of alkali in 

 the soil which would kill other vegetation. Sheep and other stock 

 are, however, able to browse on these plants and derive considerable 

 nourishment from them. Their value for stock feeding is not defi- 

 nitely known, as but few chemical analyses or digestion trials have 

 been made with them, and there are no comparative feeding trials 

 on record with these plants. The Arizona Experiment Station has 

 published analyses of salt bushes and greasewood 22 which show 

 that they contain high percentages of crude protein, fiber, and ash, 

 with medium amounts of nitrogen-free extract and fat. The fol- 

 lowing average results were obtained in the analyses of different 

 range forage crops : 



Composition of Air-dry Range Forage Plants, in" Per Cent 



As in the case of all plants growing in arid regions, the per- 

 centage of ash in these forage plants is very high, but the fiber con- 

 tent is no higher than in average grades of hay, except in the case 

 of the water grass. According to the results of the chemical analyses 

 made, greasewood contains more protein and no more fiber than 

 alfalfa hay of good quality, but, in the absence of digestion experi- 

 ments and carefully-conducted feeding trials, definite judgment can- 

 not be pronounced as to its nutritive value. The Colorado station 

 found the native and Australian salt bushes to have the following 

 digestion coefficients, according to the results obtained in trials with 

 sheep : 23 



Digestion Coefficients for Salt Bushes, in Per Cent 



22 Report, 1903, p. 349. 



23 Bulletins 93 and 135. 

 10 



