771 



ever, the same precautionary measures are necessary as with calcium nitrid. 

 It may not be used immediately before seeding, nor as a top dressing, because 

 it is then injurious \ 



In regard to the Ammonia nitrid, we should not forget to call atten- 

 tion to the fact that it may also become injurious under conditions in which 

 the nitrifying bacteria do not act sufficiently. For heavy soils, which contain 

 more water and, therefore, dissolve the ammonia more abundantly there is 

 no danger, but in sandy soils the retarded solubility may lead to direct 

 phenomena of corrosion-. 



1 Blatter, f. Zuckerrubenbau 1906, No. 10. 



2 Maze, Untersuchungen iiber die Einwirkungen des Salpeterstickstoffs und 

 des Ammoniakstickstoffs auf die Entwicklung- des Mais. Annal. agron. t. 26; cit. 

 Centralbl. f. Agrikulturchemie 1901, p. 5SS. 



