No 7. 



DEPARTMENT OP AGRICULTURE. 



279 



Three tracts of land are included in the test, so that each crop is 

 represented every season. At the same time four other pairs of 

 plots are dressed with manures of the same kind and applied in 

 the same quantity, the only difference in treatment being that the 

 manures for one pair of plots are mixed with the finely ground 

 phosphatic rock from which acid phosphate is made, and which is 

 known in the South as floats; for a second pair the manures are 

 mixed witli acid pliosphate; for a third pair with the crude potash 

 salt called kainit, and four a fourth pair with gypsum or land 

 plaster, these materials being used in all cases at the rate of 40 

 pounds per ton of manure. 



TABLE 2 — Reinforcement of Manure. 

 11 Years' Average Result. 



Manure and Treatment. 



Yield per Acre. 



3 



pq 



o 



No manure nor fertilizer, ... 



Yard, untreated, 



Stall, untreated 



Yard, with gypsum 



Stall, with gypsum 



Yard, with kainit 



Stall, with kainit 



Yard, with floats, 



Stall, with floats 



Yard, with acid phosphate, . 

 Stall, with acid phosphate, .. 

 Commercial fertilizer, 200 lbs 



3 



m 

 I 



I 



ei 

 W 



Net Value of 

 Increase. 



(U 



PL, 



c 



I 



a 

 o 



(u 



$2 27 



Valuations. 



Corn $0 40 per bu. 



Wheat SO per bu. 



Hay 8 00 per ton. 



Stover, ....• 3 00 per ton. 



Straw, 2 00 per ton. 



Cost of Treatment. 



Gypsum $1 00 per acre. 



Kainit 2 40 per acre. 



Floats 1 36 per acre. 



Acid phosphate 2 40 per acre. 



Fertilizer, 2 25 per acre. 



The outcome of this work is given in Table 2, which shows that in 

 every case the fresh manure has produced a larger increase of crop 

 than the yard manure, the average difference in value between the 

 produce of the two kinds of manure being 83 cents per ton of man- 

 ure, which is 21 per cent, of the value of the increase produced 

 by tlie fresh manure. This is a somewhat smaller difference than 

 the chemist has found, if we assume that the ton of fresh manure 

 has in the average produced a ton of yard manure; but this assump- 

 tion would undoubtedly be incorrect, for while, as I have stated, 

 the manure sometimes weighs more when taken up in the spring 

 than when put out in the fall, this is the exception, rather than the 

 rule, and in the general average there is loss in weight, as well as 

 in composition, so that there can be no doubt that the field results 

 are fully supporting those of the laboratory. 



