50 PLANT PRODUCTS 



TABLE 10. POUNDS TO OR FROM ONE Cow IN ONE DAY. 



Of the nitrogen, much better utilization is made in the 

 more digestible and watery mangels than in the dry and less 

 digestible hay. Since there is six times as much liquid in 

 the excreta from mangels there would have to be used six 

 times as much litter to obtain the same degree of conser- 

 vation. 



Storage of Farmyard Manure. The storage of the 

 manure heap is a matter of considerable practical import- 

 ance. Soon after production fermentation begins. The 

 first fermentation results in converting urea into ammo- 

 nium carbonate. During this process some ammonia may 

 be lost by fermentation and evaporation. A good supply 

 of litter acts as an absorbant for ammonia, and the loss by 

 volatilizing ammonia is probably very small under ordinary 

 farm conditions, although in town stables, where there are 

 many highly fed horses, the loss of ammonia may be so 

 sufficiently marked as to be a nuisance. General decom- 

 position produced by the actions of various bacteria soon 

 starts in the manure heap. In broad outline, the anaerobic 

 bacteria attack the fibre and proteins, which they hydrolyze 

 with the production of gummy or colloidal substances, 

 peptones, and amino-acids. The aerobes have little chance 

 of working in a fresh manure heap ; they are mostly confined 

 to the surface, where they are able to carry on their oxidizing 

 powers. The rate of action will depend upon the tempera- 

 ture, much liquid excludes air, lowers the temperature, and 

 therefore the rate of decomposition. Much carbohydrate 



