300 DRY-FARMING 



at least every third or fourth year is Hliely to be 

 dangerous in years of deficient rainfall. 



This review of the question of dry-farm fertility 

 is intended merely as a forecast of coming develop- 

 ments. At the present time soil-fertility is not giving 

 the dry-farmers great concern, but as in the countries 

 of abundant rainfall the time will come when it will 

 be equal to that of water conservation, unless indeed 

 the dry-farmers heed the lessons of the past and adopt 

 from the start jjroper practices for the maintenance 

 of the plant-f(XKl stored in the soil. The principle 

 explained in Chapter IX, tliat the amount of water 

 required for the production of one pound of water 

 diminishes as the fertility increases, shows the inti- 

 mate relationship that exists between the soil-fer- 

 tility and the soil-water and the importance of main- 

 taining dry-farm soils at a high state of fertility. 



