DRY-FARMING 



rainfall, which is probably one of the 

 main reasons for its great and sustained 

 fertility. For, while the scanty rainfall 

 has not tended to induce a luxuriant 

 growth of vegetation during ages past, it 

 has served to preserve within the soil such 

 products of decomposition as have been 

 produced; and the evaporation being 

 very great, the plant-foods have been kept 

 near the surface instead of being washed 

 away, or lost by seepage. Again, the 

 methods now devised for the conserva- 

 tion of soil moisture and the introduction 

 of drought-resistant plants are enabling 

 farmers to raise satisfactory crops even 

 in severe droughts. 



Problems. 



The problems to be solved in this 

 region are simple, but none the less im- 

 portant. How can the largest yields of 

 the four staple crops — wheat, oats, bar- 

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