96 CAMPBELL'S SOIL CULTURE MANUAL 



The plants under proper conditions show a dark, healthy 

 green color, and grows rapidly. Remember that the root 

 growth in all grains is always in excess of the plant above 

 ground, and that root growth is greatest in soil that is fine 

 and firm in which there is held all the moisture than can 

 be carried by capillary force, and that it is apparently 

 impossible by ordinary mechanical work to ^et the average 

 sand loam soil in the great semi-arid section so firm that 

 it cannot carry at the same time the necessary amount 

 of air. 



PERFECT SOIL CONDITIONS. 



Let us assume for further illustration or explanation 

 that we have just the ideal condition for holding and 

 carrying the proper quantity of air and water in the soil. 

 The sun is warming the soils, chemical action is doing its 

 work, the wheat, oats or barley is three or four inches high, 

 a rain comes of some little magnitude which dissolves 

 and packs the soil mulch on the surface, then the sun 

 comes out and the plants improve for a little time, but at 

 this point look out, for we are approaching the danger 

 point, not of the total loss of the crop but of getting the 

 highest possible yield, which should be our aim at all 

 times. 



If by certain more carefully fitted soil conditions, you 

 can get 50 bushels of wheat per acre instead of 10 to 20 

 bushels per acre, is it not worth digging for? 



This is no visionary or imposible thought, but a stern 

 truth, that only requires a little careful study and intelli- 

 gent application, after first stepping away from those old, 

 stubborn prejudices, that theory alone had prompted you 

 to cling so tenaciously to. 



The packing of the surface by the rain will cause an 



