140 DRY-FARMING 



by deep fall plowing and by proper summer fallowing 

 for the conservation of moisture, the loss of moisture 

 by direct evaporation from the lower soil layers 

 need not be larger than from finer grained soils. 



Thus again are emphasized the principles previously 

 laid down that, for the most successful dry-farming, 

 the soil should always be kept well filled with mois- 

 ture, even if it means that the land, after being broken, 

 must lie fallow for one or two seasons, until a suffi- 

 cient amount of moisture has accumulated. Further, 

 the correlative principle is emphasized that the mois- 

 ture in dry-farm lands should be stored deeply, away 

 from the immediate action of the sun's rays upon the 

 land surface. The necessity for deep soils is thus 

 again bnjught out. 



The great loss of soil moisture due to an accumu- 

 lation of water in the upper twelve inches is well 

 brought out in the experiments conducted by the 

 Utah Station. The following is selected from the 

 numerous data on the subject. Two soils, almost 

 identical in character, contained respectively 17.57 

 per cent and 16.5.5 per cent of water on an average 

 to a depth of eight feet ; that is, the total amount of 

 water held by the two soils was practically identical. 

 Owing to varying cultural treatment, the distribu- 

 tion of the water in the soil was not uniform; one 

 contained 23.22 per cent and the other 16.64 per 

 cent of water in the first twelve inches. During 

 the first seven days the soil that contained the 



