INSPECTION OF COMMERCIAL FERTILIZERS 57 



Conclusions Drawn from the Experiment. 



Dark Dried Blood. Assuming that this material is the usual fertilizer grade 

 of dried blood, its behavior is rather unexpected, both in the vegetation test and 

 when studied by the laboratorj^ methods, and does not check with the uniformly 

 good showing on the sample used in the 1928 experiment. The unusual features 

 noted in the present case are the relatively low nitrogen activity by the neutral 

 permanganate laboratory method and the low nitrogen availability of the water 

 insoluble portion of the product as measured by both dry matter yield and nitro- 

 gen recovered. It is hoped that further studies can be made on this product. 



Mowrah Meal. This is the first year's experiment with this material which 

 is being sold largely as a worm eradicator on golf greens, claims also being made 

 for its value as a source of plant food. Both the total and water insoluble nitro- 

 gen show a low availability by the vegetation test and low activity by both 

 laboratory methods. 



Horn and Hoof Meal. The results obtained this year confirm the results 

 secured on other samples for the past three years and class the nitrogen as of good 

 quahty. 



Process Tankage. About 92 per cent of the total nitrogen is in water in- 

 soluble form. This completes three years' experiments with this product, all 

 showing the water insoluble nitrogen to be of passing quality, but about 20 per 

 cent less available than that from animal tankage and fish. 



Process Tankage "Smirow." This is the first year's experiment with this 

 material. About 91 per cent of the total nitrogen is in water insoluble form. 

 Judged by either the vegetation test or the laboratory methods, it is of fair qual- 

 ity, but somewhat under that derived from fish and animal tankage. 



Garbage Tankage. This is the first year's experiment with this product. 

 About 84 per cent of the total nitrogen is in water insoluble form and all of the 

 tests, both vegetation and laboratory^ show the nitrogen to be of inferior quality. 



Omega Tankage. This is the third year that this product has been under 

 experiment. About 80 per cent of the total nitrogen is in water insoluble form, 

 and its availability is below the passing mark of 50. These results confirm those 

 secured in the 1927 experiment. On the sample tested in 1928, the availabiUty 

 of the water insoluble nitrogen was a little over 53 per cent. The laboratory 

 methods for the three years class the insoluble nitrogen as of passing quality, 

 although in one instance, 1927, the alkaline method showed an activity below 50 

 and the neutral method an activity of only 80, the passing mark. 



Nitrolene. About 35 per cent of the nitrogen is in water insoluble form and of 

 inferior quality as measured by the vegetation test. The alkaline method indi- 

 cates an activity above the passing mark; the neutral method indicates inferior 

 quaUty. When judged by the content of total nitrogen, quite satisfactory yields 

 are obtained. This completes three years' experiments on this product. 



Milorganite. This test completes three years' experiments with this product. 

 The three samples employed for the three years have shown a reasonably uniform 

 composition, and the nitrogen availability has been consistent and quite satis- 

 factory, although averaging a little below that of fish and animal tankage.. 



Rapeseed MeaL This is the first year's experiment with this material. About 

 78 per cent of the total nitrogen is insoluble in water. The availability noted is a 

 little under but compares favorably with results secured in 1928 on cottonseed 

 meal and castor pomace. 



Whale Guano. About 62 per cent of the total nitrogen is in water insoluble 

 form. The availability noted compares favorably with results secured in 1928 on 

 a similar sample and with results secured on fish and animal tankage. This 

 completes two years' experiments on this product. 



