i New York Agricultural Experiment Station. 283 

 Cost of One Pound of Plant-Food to Consumers.— Concluded. 



Lowest. Highest. Average. 



Phosphoric acid in 



Complete fertilizers (available) 



Dissolved phosphates (available) 



Fish-scrap (total) 



Bone-meal (total) 



Phosphoric acid and potash mixtures (avail- 

 able) 



Wood-ashes 



Potash in, 



Complete fertilizers 



Kainit 



Muriate of potash 



Wood-ashes 



Potash and phosphoric acid mixtures 



Cents. Cents. Cents. 



TEEMS USED IN STATING RESULTS OF ANALYSIS, 



In the tables following, the terms used to express the results of 

 analysis are self-explanatory for the most part.' Attention is 

 called, however, to "water-soluble" phosphoric acid and nitrogen. 



While manufacturers are required to guarantee only the 

 amount of available phosphoric acid (water-soluble plus reverted 

 or citrate-soluble), yet it seems desirable that consumers should 

 know what proportion of the available is water-soluble. The 

 amounts of available phosphoric acid being equal, one would 

 choose by preference a fertilizer containing the larger amount of 

 water-soluble phosphoric acid. 



The amount of water-soluble phosphoric acid varied from 0.62 

 to 9.78 per cent and averaged 5.72 per cent. This constituted 

 nearly 62 per cent of the available phosphoric acid present. 



The water-soluble nitrogen includes nitrogen present in the 

 form of ammonia salts and nitrates together with that present in 

 small amounts of soluble organic matter. The amount of water- 

 soluble nitrogen varied from to 3.02 per cent and averaged 

 0.54 per cent. This constituted 32.3 per cent of the total nitrogen 

 present. It should not be inferred that water-soluble nitrogen 

 is of more value than the rest. It is, of course, more readily 

 available, so far as it consists of nitrates, but it must be remem- 

 bered that nitrogen in this form leaches and is lost to plants more 

 readily than nitrogen in other forms. 



