Experimental Work in Dry-Farming 



609 



patches of gravel and coarse sand, except where two swales cross 

 the farm. In these a darker, finer, and more productive soil is 

 found. A stratum of "caliche" underlies the entire farm at a depth 

 of one to four feet. Mechanical and chemical analyses are reported 

 iii Tables XVI to XIX inclusive. 



About seventeen acres in the northeast corner of the farm had 

 been cultivated for several years, a good crop of beans having been 

 grown in 1912. The remainder of the farm was covered with a 

 luxuriant growth of native grasses, especially grama, galleta and 

 bluestem, and yucca. About twenty acres in the northwest corner 

 of the farm and thirty in the southwest corner were broken in the 

 winter of 1913-14; since then the remainder of the farm has been 

 used for pasture. 



The need for data having immediate, practicable application 

 was manifest. Accordingly, experimental work done on the Sul- 

 phur Spring Valley Dry-farm has been limited to investigations 



