10 



CONTROL SERIES No. 95 



Summary of Deficiencies in Mixed Fertilizers. 



Brands deficient in one element 

 Brands deficient in two elements . 

 Brands deficient in three elements . 

 Brands deficient in nitrogen . . . 

 Brands deficient in available phosphors 

 Brands deficient in potash . ■ 

 Brands deficient in magnesium oxide 



acid 



1936. 



61 



7 



2 



22 



33 



26 







1937. 



77 

 16 



2 

 39 

 29 

 47 







1938. 



89 

 20 



3 

 35 

 70 

 32 



2 



Serious Commercial Shortages in Mixed Fertilizers. 



Amount of Shortage Per Ton. 



More than $5 . 

 Between $4 and $5 

 Between $3 and $4 

 Between $2 and $3 

 Between $1 and $2 



Number or Brands According to Years. 



1935. 



1 



none 



1 

 none 



1936. 



none 

 none 



1 

 none 

 none 



1937. 



1 

 none 

 none 



3 



3 



1938. 



Out 



Of the 335 brands analyzed, 222, or 66 percent, showed no deficiencies. 

 of 1,026 plant food guarantees made, 87 percent were fully maintained. 

 The deficiency table shows the following statistics: 



Deficiencies not exceeding M of one percent, 87. 

 Deficiencies between H and Yi of one percent, 26. 

 Deficiencies between H and % of one percent, 9. 

 Deficiencies more than % of one percent, 17. 



Of the total number of guarantees of each element made, 11 percent of the nitro- 

 gen, 21 percent of the available phosphoric acid, and 10 percent of the potash 

 were not met. Twenty-six of the 35 nitrogen deficiencies, 42 of the 70 available 

 phosphoric acid deficiencies, and 18 of the 32 potash deficiencies did not exceed 



\i of one percent. , ■•*„„„„ 



Compared with the 1937 inspection, there were 4 less shortages m nitrogen, 



41 more in available phosphoric acid, and 15 less in potash. 



In the case of those fertilizers which did not conform strictly to the guarantee, 



the discrepancies were of such a character as to make it evident that there was no 



intentional attempt at violation of the regulations. 



Fourteen firms have registered five or more brands of mixed fertilizers On 

 the basis of composition found by analysis as well as upon tonnage sold, the 

 following table shows to what extent each manufacturer was successful w > avoid- 

 ing deficiencies in plant food guarantees in his mixtures. All but three of the four- 

 teen firms provided an average overrun in the three major plant food elements 

 guaranteed, considered desirable in safe fertilizer practice. 



