New York Agricultural Experiment Station. 79 



escapes into the air. (2) The nitrogen combines with hydrogen to 

 form ammonia. If the manure heap is dry, the ammonia combines 

 with carbon dioxide, forming ammonium carbonate, which may 

 escaj)e into the air and be lost to the manure. If the heap is kept 

 moist, certain organic acids are formed by the decomposition of the 

 organic matter, and the ammonia, as fast as it is formed, unites with 

 these acids, producing ammonia salts which readily dissolve in water 

 but which do not escape as gases into the air. (3) Considerable 

 water is driven off from the manure by the heat which is produced 

 in the process of fermentation. 



Diffei'ence hetween Fresh and Fermented Stahle- Manure. — From 

 the foregoing it would follow that fresh stable-manure differs from 

 fermented or " rotted " stable-manure in the following respects : 

 The fresh manure contains (1) more water, and (2) more carbon than 

 the fermented manure ; while (3) both contain the same amount of 

 potash, phosphoric acid and nitrogen, provided the process has been 

 carefully managed. In "rotted" manure, (4) the nitrogen is in a 

 more available form as plant-food ; the same is also true of the potash 

 and phosphoric acid. 



Loss of Fertilizing Materials in Stable-Manure.— There are 

 two principal ways in which stable-manure commonly loses some of 

 its fertilizing constituents : First, by improper methods of fer- 

 mentation, and second, by leaching. In regrad to the first point, 

 more or less nitrogen is lost by allowing manure to ferment without 

 sufficient moisture ; especially is this apt to be true in the case of 

 horse manure, which decomposes very rapidly. A strong odor com- 

 ing from a manure heap indicates that a wasteful fermentation is 

 taking place. Only nitrogen compounds can be lost by vaporiza- 

 tion. By leaching there will be a loss not only of nitrogen com- 

 pounds but of potash and phosphoric acid also. The common 

 method of storing farmyard-manure for several months under the 

 eaves of the barn often, if not generally, results in a loss of one-third 

 or more of the fertilizing constituents by leaching ; and, moreover, 

 the.materials thus leached out bv rain are the more easily soluble 

 portions of the manure and hence the more valuable portions. The 

 manure made by farm animals of New York State each year may 

 safely be estimated as having a value of $100,000,000, and probably 

 quite one-third of this amount is lost as a result of wastefulness in 

 not caring properly for it. 



