600 SOILS: PBOPERTIES AND MANAGEMENT 



Under conditions on the average farm such losses may 

 easily rise to 50 per cent of all the constituents, and prob- 

 ably very much higher as regards nitrogen and potash. 

 From one-half to three-fourths of the important elements 

 contained in the original food fails to again reach the 

 land. Hall, 1 quoting from Woods' experiments at Cam- 

 bridge, shows that about 10 per cent of the nitrogen in 

 the food consumed is retained by the animal. He also 

 shows that 15 per cent of nitrogen is lost during the making, 

 and from 10 to 25 per cent during the storage, of the ma- 

 nure, even under the best conditions. This gives a total 

 loss of nitrogen amounting to from 35 to 50 per cent. If 

 this is the loss under the best conditions, it can readily 

 be seen that the loss on an average farm must approach 

 65 or 75 per cent. 



Some idea as to separate losses from fermentation and 

 leaching may be gained from data drawn from Canada. 2 

 In this experiment a mixture of horse dung and cow dung 

 was divided. One-half was placed in a bin under a shed ; 

 the other half was exposed to the weather, outside in a 

 similar bin. After a year the two portions were analyzed 

 and the losses computed : — 



1 Hall > A - D - Fertilizers and Manures, p. 198. New York. 



2 Schutt, M. A. Barnyard Manure. Canadian Dept. Agr., 

 Centr, Exp. Farm, Bui. 31. 1898. 



