96 Progressive Agriculture 



leave this ridge to dry out is very wrong, but 

 double disking is much better. The advantage of 

 this disking is four fold. Keeps the weeds from 

 growing, holds the moisture in the land, causes 

 much more of each subsequent rain to go into the 

 soil and permits of easier and better plowing. 



CROPS AND THE SOIL FERTILITY 



The question is often asked, and rightly, do 

 continued big crops deplete the soil of its' avail- 

 able fertility more than small crops? 



Theoretically, possibly yes, but practically we 

 are in doubt when applied to the semi-humid 

 sections, providing good and well directed tillage 

 is carried on. Just look at Cut No. 29. Note the 

 even stand above the top wire of the fence, then 

 think that it averaged 45| bushels per acre of 

 62 pound wheat, then glance at Cut No. 21, where 

 this same field is being cut, then realize that the 

 snarled up stubble in the foreground has had a 

 tandem or double disk pulled over it with weight 

 enough on the disk to force the blades three inches 

 into the soil, and you can grasp some idea of how 

 much organic matter is available to be worked 

 into the soil. It is not only this long heavy growth 

 of stubble, but the immense growth of roots that 

 must have permeated the top soil in growing this 

 wheat. Then look at Cut No. 25 or Cut No. 27 

 and think how much stubble would be left to 

 plow under when each crop was harvested, also 

 the difference in root growth. Do you grasp the 

 significance of these facts? 



If you can keep up the organic matter in the 



