72 



T. Lyttleton Lyon and James A. Bizzell 



REMOVAL OF SULFUR 



Determinations have been made regularly of the sulfur in the form 

 of sulfates in the drainage water, and of the sulfur in the crops. The 

 average amounts of sulfur (S) removed annually from the soil by drainage 

 water during four years, and by crops for the five-years period, are given 

 in table 57: 



TABLE 57. Sulfur in Drainage Water and in Crops 

 (Pounds per acre, annual average) 



Effect of plant growth on removal of sulfur 



The removal of sulfur in the drainage water is very considerable, being 

 from three to six times as much as the removal by the crops. The ratio 

 varies with the soil treatment. As between the planted soil and the 

 bare soil there is always more sulfur removed by the drainage water from 

 the latter, but the total removal in drainage water and in crops does 

 not differ greatly, as is seen from table 58. 



There is no conservation of sulfur by cropping, as is the case with 

 nitrogen. Apparently there is a uniform conversion of sulfur into sulfuric 

 acid in both planted and bare soils, and this is in sufficient quantit}^ for 

 the needs of the plant. In fact it is probably in excess if one is to judge 

 from the large surplus that is carried off in the drainage water. It will 

 be remembered that the application of sulfur in the form of potassium 

 sulfate did not result in any increase in crop yield. This, together with 

 the liberal formation of sulfates, indicates that in this soil there is no 



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