10 



CONTROL SERIES No. 84 



Summary of Deficiencies in Mixed Fertilizers. 



Serious Commercial Shortages In Mixed Fertilizers. 



Amount of Shortage Per Ton. 



Number of Brands According to Years. 



More than $5 . 

 Between $4 and $5 

 Between $3 and $4 

 Between $2 and $3 

 Between $1 and $2 



1 

 none 

 none 



2 



1 



none 



none 



1 



1 

 none 



1 

 none 



2 



none 

 none 



1 

 none 

 none 



Of the 285 brands analyzed, 215, or 75 per cent, showed no deficiencies. 

 Out of 875 plant food guarantees made, 91 per cent were fully maintained. 

 The deficiency table shows the following statistics: 

 Deficiencies not exceeding 3^ of one per cent, 37. 

 Deficiencies between 34 and }4 of one per cent, 23. 

 Deficiencies between 14 and % of one per cent, 11. 

 Deficiencies more than H of one per cent, 10. 

 Of the total number of guarantees of each element made, 8 per cent of the 

 nitrogen, 12 per cent of the available phosphoric acid, and 9 per cent of the 

 potash were not met. Twelve of the 22 nitrogen deficiencies, 14 of the 33 

 available phosphoric acid deficiencies, and 11 of the 26 potash deficiencies did 

 not exceed 34 of o"^ Per cent. 



Compared with the 1935 inspection, there were 2 more shortages in nitrogen, 

 11 more in available phosphoric acid, and 9 more in potash. 



In the case of those fertilizers which did not conform strictly to the guar- 

 antee, the discrepancies were of such a character as to make it evident that 

 there was no intentional attempt at violation of the regulations. 



Fifteen different firms have registered five or more brands of mixed ferti- 

 lizers. On the basis of composition found by analysis as well as upon tonnage 

 sold, the following table shows to what extent each manufacturer was success- 

 ful in avoiding deficiencies in plant food guarantees in his mixtures. All but 

 two of the fifteen firms provided a satisfactory average over-run in the three 

 major plant food elements guaranteed. 



