17 



Percentage and Character of Plant Food. 



The average composition of mixed fertilizers grouped as high-analysis and low- 

 analysis is shown in the following table : — 



Form of Plant Food. 



Percentage in 

 High- analysis 

 Brands (14 Per 

 Cent or over of 

 Available 

 Plant Food). 



Percentage in 



Low-analysis 



Brands f under 



14 Per Cent 



Available 

 Plant Food). 



Total nitrogen 



Nitrogen as nitrates and ammoniates . 



Water soluble organic nitrogen 



Active water insoluble organic nitrogen 



Inactive water insoluble organic nitrogen 



Total phosphoric acid .... 



Soluble phosphoric acid 



Reverted phosphoric acid 



Insoluble phosphoric acid 



Potassium oxide ..... 



2.30 



.99 



.38 



.52 



.41 



8.73 



4.05 



3.35 



1.33 



2.52 



Nitrogen. 



About 51 per cent of the total nitrogen in the high-anal3\sis fertilizers was present 

 as nitrates or ammoniates, and about 86 per cent of the total nitrogen was in active 

 form. 



About 43 per cent of the total nitrogen in the low-analysis brands was in mineral 

 form, and 82 per cent of the total nitrogen was in active form. About 15 per cent of 

 the total number of brands analyzed failed to meet their minimum nitrogen guarantee. 



Phosphoric Acid. 



About 83 per cent of the total phosphoric acid in the high-analysis brands was in 

 available form, and 61 per cent of the available phosphoric acid was in water soluble 

 form. In the low-analysis brands about 85 per cent of the total phosphoric acid was in 

 available form, and 55 per cent of the available phosphoric acid was in water soluble 

 form. About 19 per cent of the total number of mixed fertilizers analyzed failed to 

 meet their available phosphoric acid guarantee. 



Potassium Oxide. 



Potash was used much more freely in mixed goods than for many years, the high- 

 analysis brands containing about 1 per cent more actual potash on the average than 

 during 1921, while the number of brands which did not contain potash was very 

 greatly reduced. A surprisingly large number of brands were found deficient in this 

 ingredient (about 25 per cent). Forty-four brands of tobacco fertilizer showed an 

 average of .58 per cent of chlorine, which would be equivalent to 1.16 per cent of 

 muriate of potash. 



