CONTROL SERIES. BU LLETIN NO. 6. DECEMBER, 1916 



MASSACHUSETTS 



AGRICULTURAL EXPERIMENT 



STATION. 



INSPECTION OF 



Commercial Fertilizers 



By 

 H. D. HASKINS, L. S. WALKER, C. P.JONES and W. A. ALLEN. 



This bulletin gives a detailed report of the fertilizer inspection 

 for 1916. It states the number of fertilizers registered and analyzed, 

 including a discussion of the method of sampling. It provides a 

 summary showing the average composition, cash price, as well as 

 the pound cost of each element of plant food furnished. Special 

 attention is called to commercial shortages existing in both unmixed 

 fertilizing materials and in mixed fertilizers. Summary tables show 

 the general character of the plant food contained in each manufac- 

 turer's brands of mixed complete fertilizers, and ammoniated super- 

 phosphates. The quality of the organic nitrogen in mixed fertilizers 

 has been given special attention, and the results are shown in tables, 

 including a list of those brands which were found to contain an in- 

 ferior grade of organic nitrogen. The quality of the phosphoric 

 acid and potash in fertilizer mixtures is also discussed. Mention 

 is made of the number and nature of the lime products analyzed, 

 and the influence of mechanical condition upon their activity. A 

 summary is presented of several hundred tests of the lime require- 

 ments of Massachusetts soils. An explanation of the tables of an- 

 alyses is followed by the detailed tables giving the average compo- 

 sition of all fertilizers and lime products sold in the State. 



Requests for bulletins should be addressed to the 



AGRICULTURAL EXPERIMENT STATION, 



AMHERST, MASS. 



