350 



SYSTEMS OF FARMING 



by the animals for milk production, growth, etc., and the unavoid- 

 able losses sustained in handling the manure. When the manure 

 is given the best care that can be given it under ordinary farm 

 conditions, these losses may be estimated at forty per cent for 

 nitrogen which is contained in the feeds fed, thirty per cent for 

 the phosphorus, and about twenty per cent for the potassium. 

 When the manure is left exposed to rains in an open yard even for 

 three months, these losses may run as high as fifty-six per cent for 

 nitrogen, forty-six for phosphorus, and seventy-one for potassium. 



Feed i no Transact lot 



. (Nitrogen - about 40 

 LOSS of < Phosphorus -about 30 

 (.Potassium- about 20' 



Loss of N. P, K in crops sold 



FIG. 224. Diagram illustrating the sources of loss and gain of the fertilizing elements 



in farming. 



In bedding no losses are to be considered except when manure 

 is carelessly handled. 



It is possible for a good stock farmer to return to the soil 

 about seventy per cent of the fertilizing elements contained in the 

 feeds fed and in the bedding. 



Fertilizers may be applied directly to the soil or mixed with 

 manure, as in case of phosphates. 



When feeds are purchased the manure is enriched by an amount 

 equal to the fertilizing elements contained in the feeds minus the 

 losses in the feeding transaction. 



Summary of Losses and Gains. The sources of loss and gain 



