STATE AGRICULTURAL SOCIETY. 



193 



tance to the coast being about fifty miles. The sea breeze prevails in 

 Summer, an east wind at night; liglit frosts in Winter are not severe 

 enough to injure young orange trees. There is little natural growth 

 on the soil save allilerilhi and scattering clumps of a low brush. 



The prevailing soil of the region is a reddish-brown, sandy loam, 

 containing a good deal of coarse, angular sand. This material changes 

 but slightly to the depth of from three to four feet, where it is mostly 

 underlaid by an orange-yellow hardpan, flecked with white, the white 

 spots being grains of coarse, angular sand, or rather, granitic debris, 

 consisting mainly of quartz and feldspar, with a little black horn- 

 blende, and magnelic iron ore (black sand). The liardpan appears 

 in gullies and ditches everywhere, being usually many feet in thick- 

 ness. It is quite porous, and its cement is a red clay, which softens 

 in water with little difficulty. Dry lumps can also be crushed between 

 the fingers, so that this subsoil may be considered as fairly pene- 

 trable by roots. Occasionally this hardpan approaches the surface 

 so closely as to take direct part in the formation of the soil. 



The analyses of the soil and subsoil hardpan resulted as follows: 



As regards, first, the mechanical nature of these materials, it is 

 striking that the hardj^aii subsoil contains so much less of inert sand 

 than the surface soil, although its aspect would lead to the contrary 

 conclusion. The hardi)an is considerably more retentive of moisture 

 than the surface soil, albeit the latter contains some humus to increase 

 this factor. The humus percentage of the soil is, however, very 

 small, and constitutes its chief defect, as in nearly all the mesa soils 

 of the southern region. The hardpan stratum secures the land against 

 waste of irrigation water, and against drought by its high retentive- 

 ness of moisture. 



Chemically, the surface soil is rich in potash (so heavily drawn 

 13''" 



