138 



Bulletin 394 



are higher than when the examination is made immediately after samphng. 

 Circumstances prevented the following of the latter procedure. Inasmuch 

 as the samples taken when the crop was turned under, and after the period 

 of four months, were handled identically, the figures for the difference 

 in nitrate content at these periods should not be greatly affected by the 

 increase due to drying. 



The nitrates formed during four months in the pots having the plants 

 removed or turned under after a growth of 89 days, are shown in table 

 4, and in table 5 are shown the same results for the 11 8-day s period: 



TABLE 4. Formation of Nitrates 

 (Crop turned under after 89 days growth) 



TABLE 5. Formation of Nitrates 

 (Crop turned under after 1 1 8 days growth) 



250 



