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Report of the Chemist op the 



(4) In the two years the application of 36.4 pounds of nitrogen 

 in 1,000 pounds of fertilizer caused a sufficiently increased crop 

 to remove about 13 more pounds of nitrogen than did the crop 

 from the unfertilized soil. More nitrogen was removed during 

 the two years than was added in the fertilizer by about 20 pounds. 



(5) The application of 72.8 pounds of nitrogen, contained in 

 2,000 pounds of fertilizer, caused during the two years an increase 

 of crop sufficient to use only 2.3 pounds more of nitrogen than 

 in the case where half the amount was applied. Less nitrogen 

 was removed than applied by about 14 pounds, leaving about 58 

 pounds of nitrogen unused, including the soil-nitrogen. 



(6) If we add the available nitrogen contained in the soil to 

 that supplied in the fertilizer, and then indicate the amounts used 

 each year, we can prepare the following interesting table. 



It is more than probable that the unfertilized soil would still 

 contain some available nitrogen and would not be completely 

 exhausted, but how much remains we could only tell by further 

 investigation. The amount of nitrogen supplied in 1,000 pounds 

 of fertilizer is not greatly in excess of the crop's needs for two 

 years; but, it is safe to say, more economical results would have 

 been obtained by applying one-half of the amount during each 

 of two years than the whole amount during the first year, par- 

 ticularly on soil which is so apt to lose nitrogen by leaching. 

 Much more, then, would the foregoing statement apply to the 

 case where we used 2,000 pounds of fertilizer and supplied three 

 times as much as the first crop used. At the end of two years it 

 is almost certain that very little of the applied nitrogen remained 

 within reach of the plant and most of the remaining 57 pounds 

 had been carried far down into the subsoil. 



