WATER IN THE SUBSOIL 



117 



as the lower soil layers are moistened, the water is 

 enabled, so to speak, to slide down more easily into 

 the depths of the soil. 



This is a very im])ortant principle for the dry- 



Fig. 31. Dry-farm Kubanka spring wheat, 1909. Fergus Go., Montana. 

 Yield, 3.5 Ijuslicls per acre. 



farmer to understand. It is always dangerous to 

 permit the soil of a dry-farm to become very dry, 

 especially below the first foot. Dry-farms should 

 be so manipulated that even at the harvesting season 

 a comparatively large quantity of water remains in 



