RELATIONS OF FEEDING TO FERTILITY. 41 



half cents for tiie i)lK)s[)]i()ric iieid, mul seven cents for the potash 

 there is in it ; and if you i<now how many pounds of nitrogen 30U 

 are paying for and getting, how many pounds of phosplioric acid 

 you are buying, and how man}' pounds of potash you are buying, 

 you know whether you are getting your money's worth or not. 



Now the question is, what it would cost to replace the amount of 

 fertilizing material that tliere is in a ton of English hay by the 

 purchase of commercial fertilizers. 



In a ton of English hay there are thirty-one pounds of nitrogen. 

 If that was worth twenty-five cents a pound, the rate I have named, 

 vou see there would be seven dollars and seventv-five cents worth in 

 a ton of ha3\ But there must be a deduction, for in this P^nglish 

 hay the nitrogen is in a different form from what it is in superphos- 

 phate ; it is in a form not readil}' available for plant food, and conse- 

 quently it cannot be reckoned at its full value. The form in which 

 it exists in English hay is about the same as it comes in raw porgy 

 chum ; and the nitrogen in that is reckoned at the experiment station 

 and at phosphate manufactories, in that condition, about twenty 

 cents per pound. For a hke reason, the phosphoric acid is rated at 

 about seven cents per pound, and potash at about four cents. At 

 the rate of using these values the fertilizing elements in one ton of 

 hay would be worth seven dollars and sixt3^-three cents. 



In feeding this hay to stock, a portion of this material as we have 

 seen is retained by the animal, and the remainder is thrown off in 

 tlie voidings, and is retained on the farm in the form of barn manure. 

 This reduction through feeding reduces the available manure to a 

 less value than that of the total contents of the material before 

 being fed. When comparing the same with commercial manures it 

 is also proper to discount for the bulkier form of the barn manures. 

 With their valuable contents is a large amount of material of no 

 value which must be handled and applied in order to avail ourselves 

 of this small quantity of fertilizing material. Making a discount of 

 twenty per cent, for this, and we have the manure value of hay and 

 other stock fodders fed out to our farm stock as in the following 

 table : 



