THE CAMPBELL SYSTEM 



and what he terms "Summer Culture." 1 

 The credit, however, of introducing this 

 system undoubtedly belongs to the agri- 

 culturists of Utah, who have successfully 

 used moisture-saving summer fallows in 

 dry-land farming for over forty years. 



In the springtime, as soon as the frost 

 is well out of the ground, land that has 

 already been plowed is gone over twice 

 with a disc harrow. This produces a 

 mulch which prevents evaporation ; it also 

 opens and loosens the surface, so that the 

 rains quickly percolate into the soil. The 

 land is then harrowed after each rain with 

 an ordinary harrow. If the rain is so 

 heavy as to pack the surface of the soil, 

 the disc harrow must again be used. 

 Naturally, the kind of tool for each sub- 

 sequent cultivation will depend upon the 

 state of the land, the rainfall, and the 



1 This name is rather vague : summer tillage and sum- 

 mer tilled are better terms. 



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