Manurial Value of Feeding Stuffs. 



247 



The great variation in quantity and composition of animal excre- 

 ments, owing to difference in the feeds consumed, is shown by War- 

 ington.^ In one feeding trial each cow of one lot was fed 154 lbs, 

 of mangels daily, while each cow of another lot received 26 lbs. of 

 alfalfa hay and 66 lbs. of water daily. The results are shown be- 

 low: 



Amount and composition of excrement voided daily hy cows fed mangels 

 or alfalfa hay. 



The cows fed watery mangels voided 6 times as much urine as 

 those fed alfalfa, but the urine of the latter was 13 times richer 

 in nitrogen and 3 times richer in potash than the urine from those 

 eating mangels. This plainly illustrates that the quality of manure 

 depends primarily upon the nature of the feed. 



383. Composition of fresh excrements. — The quantity of nitrogen, 

 phosphoric acid, and potash in the voidings of farm animals de- 

 pends primarily upon the amount of each supplied in the feed, and 

 secondarily upon the animal to which the feed is given. While it 

 is impossible to formulate anything like an exact table showing the 

 composition of the excrements of the different classes of farm ani- 

 mals, the following, originally from Wolff,- is helpful : 



Fertilizing constituents in 1,000 lbs. of fresh excrements of farm animals. 



*The alkalies include potash, lime, etc. 



Chemistry of the Farm, p. 218. 



Bailey, Cyc. Amer. Agr., Vol. I, p. 491. 



