366 



THE PRINCIPLES OF SOIL MANAGEMENT 



to it stands hog excrement, and cow excrement is the 

 poorest in fertilizing materials. 



235. Urine. The urine represents a portion of the 

 food which has been digested by the animal and excreted 

 as a waste product through the kidneys. The proportion 

 of the nitrogen and mineral matter retained by the tis- 

 sues depends upon the age of the animal and upon the 

 nature of the food. An animal receiving a large amount 

 of easily digestible nitrogenous food excretes more nitro- 

 gen in the urine than a poorly fed animal. 



The composition of urine, as given by Stoeckhardt is 

 as follows: 



Table LIII 



Horse (hay and oats) 



Cow (hay and potatoes) 



Swine (winter food) 



Sheep (two pounds hay per day) 



Water 



Per cent 

 89.0 

 92.0 

 97.5 

 86.5 



Composition of dry matter 



Nitro- 

 gen 



Per cent 

 10.9 

 10.0 

 12.0 

 10.4 



Phos- 

 phoric 

 acid 



Per cent 



trace 



trace 



5.0 



3.7 



Alkalies 



Per cent 



13.6 



17.5 



8.0 



14.9 



These figures show the following number of pounds 

 of each constituent in 1,000 pounds of urine. 



Table LIV 



