No. 5. 



DEPARTMENT OF AGRICULTURE. 

 THE REINFORCEMENT OF MANURE 



40o 



Yard, untreated 19.8 9.5 1 890 $23 85 $2 98 



Fresh, untreated 24.0 10.8 1,470 30 15 3 77 



Yard, and floats 25.2 12.5 1,637 I 3178 3 97 



Fresh and floats 31.5 14.7 2,396' 40 93 5 11 



Yard and acid phosphate, 31.4 15.3 1,904 38 67 4 83 



Fresh and acid phosphate, 35.1 16.1 2,583 44 26 5 53 



Average unmanured yield 34.3 11.5 2,717 .... .... 



Valuation: corn, 50c per bu.; wheat, 80c per bu.; hay, $10 per ton. 



The manure is applied at the rate of eight tons per acre to corn, 

 in a three year rotation of corn, wheat and clover, each crop being 

 gro^vTi every season, and the table shows the outcome of eighteen 

 years work. In computing the net value of the increase the cost of 

 treatment is deducted, on the basis of the cost of the materials in 

 bulk carloads, which would be about |7.50 per ton for floats and 

 111.50 for acid phosphate, or about 15 cents per ton for manure for 

 floats and 23 cents for acid phosphate. No allowance is made for 

 the extra labor of handing the larger crops produced by the treat- 

 ment, nor for the additional value of the straw and stover. 



When the experiment was begun, it was expected that the floats, 

 while it might be slower in action at first, would eventually produce 

 the larger effect, because a ton of floats carries about twice as much 

 total phosphorus as a ton of acid phosphate, but this expectation has 

 not been realized. On the contrary, the acid phosphate is gaining 

 relatively on the floats, as shown by the comparison below of the 

 value of the produce of a ton of manure in these experiments for the 

 first three rotations, or nine years, compared with the value of the 

 nine years following: 



INCREASING EFFECTIVENESS OP MANURE 



Yard, untreated, 



Fresh, untreated 



Yard and floats 



Fresh and floats, 



Yard and acid phosphate. 

 Fresh and acid phosphate, 



$1 36 

 1 90 

 65 



58 



1 46 

 97 



