COMPOSITION OF ANIMAL MANURES 373 



decompose the ammonium compounds with liberation 

 and loss of free ammonia. An absorbent, such as land 

 plaster, superphosphate, kainit or dry earth will greatly 

 lessen the loss of nitrogen. Mixing it with other manures 

 is also advisable. 



When applied to the soil, poultry manure decom- 

 poses rapidly, and is used by market gardeners on account 

 of its rapid action. 



244. Factors affecting the values of farm manures. 

 The value of animal excrements for manurial purposes 

 depends upon a number of factors, among which are: 

 (1) The relative proportions of solid excrement and 

 urine. (2) The species of animal producing the manure. 

 (3) The age of the animal. (4) The character of the food 

 the animal receives. (5) The use to which the animal 

 is being put. In addition to the factors affecting 

 the excrement, the manure may always be modified 

 by the litter or other absorbent added, and by the 

 method of handling. The effects of solid and liquid 

 excreta, and of the species of animal, have already been 

 discussed. 



245. Age of animal. A young and growing animal 

 requires more nitrogen and phosphoric acid to build 

 bone and muscle than does an animal that has completed 

 its growth. This is taken from the food, and not excreted 

 in the urine or other excretory products, and hence does 

 not appear in the manure. 



246. Food of the animal. Since the large part of the 

 nitrogen phosphorus and potassium contained in the 

 food is contained in either the solid or liquid excrement, 

 it follows that the richer the food in these constituents 



