CROPS AND SOIL IMPROVEMENT 



good tilth by organic matter and tillage. The 

 depth of this soil affects the amount of available 

 plant-food and water. The duration of time 

 between deep plowings depends upon the soil and 

 the crops. Experience shows that when land has 

 been broken for corn or potatoes or beans or similar 

 crop, the one plowing may be sufficient for a suc- 

 ceeding crop. If grass is not seeded with the 

 succeeding crop, it is best to give another thorough 

 plowing before seeding to grass in August if the 

 soil is heavy, but in naturally loose soils a disk 

 harrow makes a better seed-bed. 



Two influences favor such undue dependence 

 upon a disk harrow that a soil may become shallow: 

 the cost of preparing the seed-bed is reduced, and 

 the saving in moisture may give a better stand of 

 plants when the harrow takes the place of the plow. 

 The immediate productiveness of a crop is not an 

 assurance that the method is right: considera- 

 tion for the good of the land must be shown. 

 Depth of soil is a requirement of a good agricul- 

 ture, and deep plowing is a means to that end. 

 The looseness of the soil and the character of the 

 season may make substitution right in one in- 

 stance and wrong in another. Deep soils, well 

 filled with organic matter, will bear shallow prep- 



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