INSPECTION OF COMMERCIAL FERTILIZERS 4 



Agrinite. This is the second year that this product has been under experi- 

 ment. About 69 per cent of the total nitrogen was in water insoUible form. 

 Although its availability was quite satisfactory, yet it was nearly 20 per cent 

 under that from fish and animal tankage and about 18 per cent under the avail- 

 ability recorded for the Agrinite sample under experiment in 1927. 



Nitrolene. About 30 per cent of the total nitrogen was in water insoluble 

 forms and was of inferior quality. The results confirm our experiment on this 

 product in 1927. 



Whale Guano. About 65 per cent of the total nitrogen was in water insoluble 

 form. Its availabihty was fairly satisfactory, being only about 10 per cent 

 under that for fish and animal tankage. The material has been under experi- 

 ment only one year. 



Dry Ground Fish, Cottonseed Meal, Castor Pomace, Packing House 

 Tankage (9.5% ammonia grade) and Packing House Tankage (10% ammo- 

 nia grade). As was expected, these five products showed very satisfactory 

 availability, thus confirming earlier experiments with these valuable sources 

 of organic nitrogen. 



Omega Tankage. About 82 per cent of the total nitrogen was in water 

 insoluble form. It showed an availability of passing quality, although about 

 21 per cent under that for fish and animal tankage. It showed an improvement 

 over last year when the insoluble nitrogen was below the passing mark of 50 

 per cent. 



Super Nite. About 92 per cent of the total nitrogen was in water insoluble 

 form. It showed a satisfactory availability, being only about 4 per cent under 

 that for fish and animal tankage. 



Avail Tankage. About 78 per cent of the total nitrogen was in water insol- 

 uble forms. Its availability was about on the passing mark of 50 per cent, 

 which was only a little better showing than for 1927. On the average its avail- 

 ability is about 25 per cent under that for fish and animal tankage. 



Nitrogenous Tankage. About 99 per cent of the total nitrogen was in 

 forms insoluble in water. Its availability, although slightly above the passing 

 quality and a little better than for the previous two years, shows that the quality 

 of the nitrogen is not of the best, being about 23 per cent under that for fish and 

 animal tankage. 



Uric Acid. Although this material is not of commercial importance as a 

 source of organic nitrogen for fertilizer, it was included in the experiment in an 

 attempt to explain the low activity sometimes secured by the alkaline method 

 on Peruvian guano, a product likely to contain varying amounts of uric acid. 

 Its nitrogen is practically all in water insoluble form, and judging from this 

 experiment, is of excellent quality, surpassing that of dried blood. 



The Effect of Manganese Carbonate. No significant increases in yield 

 were noted on any of the amounts used. 



