132 Maine; agriculturai. Experiment station. 1912. 



its nitrogen as nitrate. If much more is present it is liable tO' 

 loss from leaching. If much less is present the plant will not 

 have enough immediately available nitrogen. Most of the 

 manufacturers do not appear to attach sufficient importance to> 

 this feature. They frequently substitute ammonium sulphate 

 or organic nitrogen for nitrate nitrogen, seeming to have, only 

 the total nitrogen in mind. The figures given in the tables 

 appear to bear out this statement. 



This is indicated by the following variations in different 

 samples of high grade brands. In each instance the total nitro- 

 gen was up to the guarantee. The sources of nitrogen, as indi- 

 cated by the variations in nitrate nitrogen, differed greatly in 

 different lots of the same brand, as shown by the following; 

 examples : 



Great Eastern High Grade Potato Manure, nitrate nitrogen 

 varies from .51 per cent to 1.72 per cent. 



Bowker's Potato and Vegetable Phosphate, nitrate nitrogen 

 varies from none to .76 per cent. 



Buffalo 4-6-10, nitrate nitrogen varies from 0.34 per cent tO' 

 1.30 per cent. 



Bradley's Potato Fertilizer, nitrate nitrogen varies from 0.36 

 per cent to 1.13 per cent. 



Crocker's Special Potato Manure, nitrate nitrogen varies 

 from 0.51 per cent to i.io per cent. 



The above brands represent some of the highest priced fer- 

 tilizers sold in the State. It would seem that one should have 

 the right to expect that they would be uniformly made and 

 mixed. The variations in nitrate nitrogen content seem to indi- 

 cate that too little importance is attached by the manufacturer 

 to the forms of nitrogen in a definite brand. 



The sources and kinds of plant food entering into a fertilizer 

 are frequently as important to the planter as are the total 

 amounts of nitrogen, phosphoric acid and potash. The chief 

 reason for many planters using home-mixed goods is the knowl- 

 edge they have of their composition. Now that the attention of 

 the planter is being called to these variations in the makeup of 

 fertilizers he may demand changes in the fertilizer law so that 

 the kind and amount of constituents entering into the manufac- 

 ture of a given brand of fertilizer must be stated as part of the 

 brand. It is largely up to the manufacturer to determine by 

 his practice whether such legislation will have to he sought. 



