8 



N. H. AGR. EXPERIMENT STATION [Bulletin 206 



8.11 per cent, available phosphoric acid and 2.49 per cent, 

 available potash. The value of the 8.11 units of phosphoric 

 acid was 8.11 X $1.48 or $12.00. The value of the 2.49 

 units of potash was 2.49 X $1-35 or $3.36. The value of 

 the available phosphoric acid and potash was $12.00 plus 

 $3.36 or $15.36 and the nitrogen cost $45.50 minus $15.36 

 or $30.14. The average content of nitrogen was 0.97 per 

 cent. One ton then contained 0.0097x2000 or 19.4 pounds 

 of nitrogen. The cost per pound of nitrogen was $30.14 

 -^19.4 or $1.55 and the cost per unit was 20 X $1.55 or 

 $31.00. On the same basis the average cost per unit of 

 nitrogen in the 5-8-7 fertilizer was $7.61 or approximately 

 one-fourth as much. It 'pays to compare the relative values 

 vjhen purchasing fertilizer. The high analysis fertilisers 

 furnish the plant food at a lotver cost than the loiv analysis 

 goods. Table No. 1 gives the cost of nitrogen in the dif- 

 ferent brands of complete fertilizers and sheep manures 

 analyzed during the past season. 



TABLE NO. I 



Relative Cost of Nitrogen in the Various Complete Fertil- 

 izers and Sheep Manures 



