752 
Journal of Agricultural Research 
Vol. XXVIII, No. 8 
Desert-sage in the Gila Valley indicates a soil texture (Table XII) differing 
very little from that of the creosote bush land, but much coarser than that of 
the desert-sage land in Coachella Valley (Table X). In the spring of 1915 
there was available soil moisture to a depth of 4 feet. In the fall the moisture 
had been exhausted in the first and second feet of soil, but in some instances 
there was still available moisture in the third and fourth feet. This was due 
to the shallow root systems developed above a hard pan or heavy alkaline soil 
(Table XIII). That the available soil moisture was greater in spring than that 
in the creosote bush land was due probably to the creosote bush being on higher 
and warmer lands where growth begins earlier in the spring and uses the available 
soil moisture sooner. At the time these samples were taken, the latter part of 
March, the annuals on the creosote bush land were already beginning to wither 
and turn yellow. Those on the desert-sage land were still in their prime. At 
Casa Grande the soil texture of desert-sage land is much like that at Chandler, 
but lighter than in Coachella Valley. There is no water available in any of the 
4 feet of soil in the fall. 
