WATER CONTENT OF FIELD SOILS 



157 



therefore pulverizing operations attain their maximum 

 efficiency with the minimum of work. (See page 103.) 

 A soil always tilled in this condition should never get 

 into bad tilth. 



.33 0.09 



.02 



.01 



.24 1.49 



.01 .23 

 RAINFALL IN INCHES 



Fig. 50. Curve showing moisture content of silt loam blue-grass soil, 

 Lexington, Kentucky, September, 1896. 



76. Available water in some field soils. The actual 

 moisture content and fluctuations through a part of the 

 growing season for different soils is always of prime 

 concern to the farmer. The following curves, (Figs. 



RAINFALL IN INCHES 



.54-1.42 



Fig. 51. 



Curve showing moisture content of clay soil black cretaceous 

 prairie Macon, Mississippi, July, 1896. 



49, 50 and 51) based upon the results of Whitney and 

 Hosmer, illustrate these fluctuations. 



If we assume for the above soils a porosity of 47, 52, 

 and 65 per cent, respectively, their weights per cubic 



