86 THE: RAISIN INDUSTRY. 



they will forever be out of the reach of the vines. To ascertain these 

 facts and conditions, every vineyardist should have the soil analyzed 

 about every five years, and too great care cannot be taken to keep the 

 soil of proper strength. 



Another influence of irrigation on the soil may also be mentioned 

 here. Some of the soils in the irrigated districts which were formerly 

 very hard and difficult to work have in course of time changed and 

 become mellow. The water has undoubtedly caused a chemical and 

 mechanical decomposition of the components of the soil, which has 

 caused it to continually improve. Bven certain kinds of hardpan 

 have been known to dissolve when irrigated, and to change into useful 

 and mellow soil, in which the vines can find nutriment. Such hard- 

 pans are those which are generally found in very dark red soils; those 

 in lighter soils are not so readily dissolved. 



