160 University of California Fublications in Agricultural Sciences [Vol. 1 



Miscellaneous Series 



For tlie purpose of comparing sheep and goat manure as well 

 as phosphatic guano with the other organic materials above 

 described and with peptone, it was deemed of interest to obtain 

 data exemplifying the ammonification in the same soil of all the 

 different materials above used with the three additional ones just 

 mentioned. The sandy soil was chosen for this series and when 

 peptone (Witte) was used, 0.5 gram of it was added to 50 grams 

 of soil. The peptone contained 14.14 per cent N. The sheep 

 and goat manure (2.13 per cent N), owing to its low nitrogen 

 content, was added to the extent of 3 grams per 50 grams of soil, 

 and the phosphatic guano (3.96 per cent N) was also added at 

 the rate of 3 grams per 50 grams of soil. The results obtained 

 are recorded in Table VII. 



As was to be expected, the very available form of nitrogen 

 in the peptone allows of the production of much larger quantities 

 of ammonia than do the less available forms of the other materials. 

 The fineness of division and easy solubility of the peptone, as well 

 as the form of nitrogen which it contains, doubtless have con- 

 tributed to the results. The more or less uniform decomposition 

 of it, however, by most of the organisms tested shows peptone to be 

 unsuited, as has been claimed by other investigators, for ammoni- 

 fication studies with pure or mixed cultures when the application 

 of the data obtained, to field conditions, is contemplated. How- 

 ever that may be, Sarcina lutea shows the highest efficiency at 

 ammonifying peptone nitrogen and at least six other organisms 

 approach it rather closely. Relatively speaking, all but two of 

 the organisms tested are efficient ammonifiers of peptone nitrogen. 

 But their position with respect to peptone, as can be seen from 

 Table VII, is no criterion as to their efficiency with respect to 

 the other materials. 



One of the interesting facts about the ammonification of the 

 sheep and goat manure by pure cultures is that only one organism 

 showed ammonifying efficiency worthy of the name, and that was 

 B. megatherium. The other organisms showed a very slight 

 power only of ammonifying the nitrogen in it. Just why this 

 large discrepancy should exist with respect to this manure 

 between B. megatherium and the other organisms still remains 



