142 



DRY-FARMING 



Fig. 33. Many soils cheek badly. The cracks cause a loss of soil mois- 

 ture. Arid soils (this picture represents a heavy clay as depicted by 

 Lyon and Fippin) often crack extensively. Cultivation will prevent 



the loss of soil-moisture. 



almost wholly at the surface. Yet it is well known 

 that evaporation from the soil surface may continue 

 until the soil-moisture to a depth of eight or ten 



