416 



STATE BOARD OF AGRICULTURE 



is a tendency toward a somewhat higher pH value in the solutions of 

 greatest volume, although this tendency is not well marked. 



Table 2. — Effect of volume of solution — treated and untreated soils. lOgms. of soil. 



APPLICATION OF FOREGOING METHODS 



A series of soils was selected covering a range in pH from 4.73 to 

 8.12 and the foregoing methods for active bases and excess acids ap- 

 plied to them in order to determine the possible correlations. These 

 results are given in Table 3, and show, apparently, an important re- 

 lationship between the ba.se — acid ratio and the pH of the soils. Since 

 only the total quantities of bases and acids are determined, the results 

 are given in terms of calcium equivalents. Quantities of total active 

 acids were obtained by adding results for active bases to those for excess 

 acids, assuming that the active bases were combined with an equivalent 

 of active acids. These results may also be considered a check on the 

 accuracy of the methods. 



Table 3. — Showing relationships between sctive soil bases, acids and pH. Results in lbs. 

 expressed as lbs. calcium to 2,000,000 lbs of soil. 



