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T. Lyttleton Lyon and James A. Bizzell 



The larger quantity of sulfur in the drainage water of the limed soil 

 appears to be sufficiently well marked and constant to indicate a con- 

 nection between the treatment and the result, especially as the sulfur 

 in the drainage water from tanks 11 and 12 has the same relation to the 

 lime treatment. It seems likely that the biological process by which sulfur 

 is oxidized in the soil is favored by the presence. of a sufficient quantity 

 of lime, just as is the process of nitrate formation. 



Effect of potassium sulfate on removal of sulfur 



The fate of the sulfate applied to the soil is in part indicated by these 

 experiments. Tanks 11 and 12, each of which received an annual appli- 

 cation of 200 pounds per acre of commercial sulfate of potash, equivalent 

 to about 35 pounds of sulfur, lost more sulfur in the drainage water than 

 did the soil not so treated, as is shown in table 60: 



TABLE 60. Average Annual Removal of Sulfur from Soil Treated and from Soil 



Not Treated with Sulfate of Potash 



(In pounds per acre) 



The drainage water removed about 20 pounds more sulfur per acre 

 from the soil to which sulfate of potash had been applied than from the 

 soil not so treated, but the crop did not show increased removal. From 

 these figures it may be inferred that over one-half of the total sulfur 

 added in the form of sulfate was removed in the drainage water. As 

 compared with most substances added to the soil as a fertilizer, this is 

 a large loss. It raises the question whether the use of sulfates as a source 

 of sulfur is economical, and whether it is not better to supply this material 

 in the form of organic matter. It is true that sulfate is frequently present 

 in fertiUzers as an accidental constituent and adds nothing to the cost of 



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