92 CAMPBELL'S SOIL CULTUKE MANUAL 



do, and yet so very little has been accomplished in 

 increasing the average yield of our great and magnificent 

 prairies. 



The average yield of all grains in Nebraska and Kansas 

 in 1906 was from 15 to 30 per cent greater than any one 

 previous year in the past twenty years. Many say 

 this is due to more favorable climatic conditions, but this 

 is not wholly true. A good portion is due to a better 

 knowledge of the soils and how to till them; and yet it is 

 possible by a still more comprehensive knowledge of these 

 soils and what physical condition it is necessary to reach to- 

 gether with the how, when and where, to attain that de- 

 gree that we may be able to liberate and utilize all na- 

 tures' resources. We shall then see the average yield as 

 shown in the above states in 1906, easily doubled, and 

 what is true of these states is proportionately true of all 

 other similar states. Why this subject, so vital to the 

 the welfare of our country, has been so neglected in the 

 past we cannot comprehend. 



There will be some little gained by seed breeding and 

 seed selection and a little by acclimating plants, a little 

 by crop rotation, but not until rotation is better 

 understood than it is now. Possibly some -material gain 

 may be made by the introduction of the so-called drouth- 

 resisting plants. But the great and lasting change that 

 is certainly on its way, must come through a broader 

 and more practical knowledge of soil physics. 



FORCES THAT AWAIT DEVELOPMENT., 



Few tillers of the soil realize how easily the silent 

 forces that lie beneath our feet within this inert soil over 

 which we walk and have been taught to almost shun, can 

 by timely direction and control be made to minister unto 

 us by yielding up from mother earth bountiful crops. Sad 



