BARNYARD MANURE 



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different sources, as was noticed in the last chapter. They 

 then treat these materials in many different ways and 

 compound the products into various combinations to meet 

 the varying needs of farmers. 



82. Fertilizer Formulas. The composition of commercial 

 fertilizers is expressed by formulas. If we say the formula 

 for a certain brand of fertilizer is 2-8-10, we mean that 



PROPER CARE OF MANURE. 

 Note the location of the pile under a shed. 



the minimum guarantee for the fertilizer is 2 per cent 

 nitrogen, 8 per cent phosphoric acid, and 10 per cent potash. 

 This order, you will notice, is the alphabetical one. In 

 the general trade, nitrogen is usually expressed as am- 

 monia, fourteen seventeenths of which is nitrogen. 



83. Barnyard manure consists of the solid and liquid 

 excreta of the farm animals, together with the absorbents 

 employed. Its most valuable fertilizing influences are in- 

 direct. The large amount of vegetable matter in it be- 



