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that tree growing is just like the growing of other things, 

 that it all depends on the care and preparation of the 

 soil and intelligent application of the principles of scien- 

 tific soil culture. The present error is the inclination to 

 be satisfied with a fair ordinary growth. Don't do that. 

 Get all nature can give up to you. 



It is useless to apply commercial fertilizers to lands 

 which are not in proper physical condition for the very 

 best growth of crops. Prof. L. H. Bailey, 



We find by the Campbell system that we can as well 

 keep moisture in the ground as to put it in a jug and put 

 in the cork. J. B. Beal, Chief Land Examiner Union Pacific 

 Railroad. 



Nitrogen Supply. Considering all these facts and the 

 additional facts that there are about seventy-five million 

 pounds of atmospheric nitrogen resting upon every acre of 

 land, and that it is impossible to obtain unlimited quanti- 

 ties of nitrogen from the air for the use of farm crops, and 

 at very small cost, the inevitable conclusion is that the in- 

 exhaustible supply of nitrogen in the air is the store from 

 which we must draw to maintain a sufficient amount of 

 this element in the soil for the most profitable crop yields. 

 -Prof. Cyril G. Hopkins. 



