Lysimeter Experiments 



53 



TABLE 37. Average Annual Removal of Magnesium from Soil Treated and from 

 Soil Not Treated with Sulfate of Potash 



There is a substitution of potassium for magnesium when the soil is 

 treated with this fertihzer, altho quantitatively it is not so great as the 

 substitution of potassium for calcium. Both these substitutions serve to 

 emphasize the strong retentiveness of the soil for potassium. 



Percentage of magnesium in plants 



The effect of the lime application on the percentage of magnesium 

 in the crops was not, on the whole, similar to its effect on the calcium. 

 The effect on magnesium is shown in table 38: 



TABLE 38. Percentage of Magnesium in Crops Raised on Limed and on Unlimed 



Soil 



There is not so much uniformity in the percentage of magnesium in 

 these crops as is shown in the percentage of calcium, and there can hardly 

 be said to be any relation between the application of lime and the per- 

 centage of magnesium in the crops. 



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