WASTE OF MANURE BY LEACHING 377 



rally take the form of a sulfate, which protects this por- 

 tion from volatilization. 



The other fermentation resulting in the loss of nitro- 

 gen is due to the action of certain anaerobic bacteria 

 that convert ammonium salts into free nitrogen. Certain 

 of these organisms are able to reduce nitrates to nitrites, 

 and the latter to ammonia, but the greatest loss is doubt- 

 less due to the ammonium salts formed directly from 

 proteins. This process occurs only in the poorly aerated 

 portions of the heap. There does not appear to be as 

 great loss of nitrogen through the action of the anaerobic 

 ferments as through the loss of ammonia, which makes 

 it advisable, in practice, to keep the manure heap as 

 compact as possible, and to prevent the heap from be- 

 coming very dry by the application of water in amounts 

 sufficient to keep the heap moderately moist without 

 leaching it. In the arid and semi-arid parts of the coun- 

 try, this is an important precaution to be taken in the 

 preservation of farm manure. 



250. Leaching. When water is allowed to soak 

 through a manure heap and to drain away from it, there 

 is carried off in solution and in suspension a certain 

 quantity of organic and inorganic compounds contain- 

 ing nitrogen as urea, other organic nitrogen in small 

 amounts, ammonium salts and nitrates, some phos- 

 phorus and considerable potassium, with other mineral 

 substances of less importance. The amount of loss to the 

 manure in this way may be very great; and, without 

 doubt, in the humid portions of the country leaching 

 is the greatest source of loss. Protection of manure from 

 the rain is therefore very important. 



