30 



The Bulletin 



Effect of Varying Quantities of Phosphoric Acid. 



The above experiments in Table 3 were planned to show the effect on 

 yields of corn and stover of varying quantities of phosphoric acid, the 

 nitrogen and potash remaining the same. On one plat one-half the 

 normal quantity of phosphoric acid was applied or an amount repre- 

 sented by 75 pounds of 14 per cent acid phosphate and equivalent to 

 3% per cent phosphoric acid in the fertilizer mixture. On two plats 

 were applied two and three times the normal quantities of phosphoric 



TABLE IV.— RESULTS OF FERTILIZER EXPERIMENTS WITH CORN— 



Results in Old Field 



Number 



of 



Plat 



Fertilizer Application Per Acre 



d b 



M -S « 



o ^' oOh 

 -O^ t3t3 

 3" sis 



^ PM 



o 



o 



pti 



Yield in Bushels of 

 Shelled Corn Per Acre 



PM 



^ 1903 1904 1909 Ave 



82 



12 



92 



102 



10 » 

 6» 



Unfertilized 



69.2 Pounds 13% 



1 150 Pounds 14% 

 22.5 Pounds 20% 

 69.2 Pounds 13% 

 150 Pounds 14% 

 45 Pounds 20% 

 69.2 Pounds 13% 

 150 Pounds 14% 

 67.5 Pounds 20% 

 69.2 Pounds 13% 



1 150 Pounds 14% 



11.2 Pounds 20% 



Unfertilized 



Blood 



Acid Phosphate- 

 Manure Salt 



Blood... 



Acid Phosphate- 

 Manure Salt 



Blood 



Acid Phosphate. 



Manure Salt 



Blood 



Acid Phosphate.- 

 Manure Salt... . 



....0= 



...-N= 

 ....P= 

 ....K= 



....N= 

 ....P= 



..2 K= 



....N=j 



— P= 

 .-3 K= 



....N=; 



...-0= 



21 



4.5 



21 



21 



13.5 



21 



2.2 



22.9 

 28.6 



24.3 



22.0 



29.2 

 21.3 



29.9 

 36.4 



30.7 



32.9 



36.4 

 25.6 



26.4 

 32.5 



27.5 



27.45 



32.8 

 23.5 



Results in Field A 



1905 



1907 



1909 



Ave. 



42 

 7 

 10 



52 



62 



72 



69.2 Pounds 13% Blood N= 



150 Pounds 14% Acid Phosphate .P= 



11.2 Pounds 20% Manure Salt }4 K= 



Unfertilized 0= 



69.2 Pounds 13% Blood .N= 



150 Pounds 14% Acid Phosphate P= 



22.5 Pounds 20% Manure Salt .K= 



69.2 Pounds 13% Blood _.N= 



150 Pounds 14% Acid Phosphate P= 



45 Pounds 20% Manure Salt .2 K= 



69.2 Pounds 13% Blood ..N= 



150 Pounds 14% Acid Phosphate P= 



67.5 Pounds 20% Manure Salt 3 K= 



Unfertilized 0= 



21 



2.2 



21 



4.5 



21 



21 



13.51 



22.3 

 27.3 

 23.6 



23.2 



24.4 

 23.4 



30.5 

 32.5 

 31.2 



31.2 



37.4 

 26.5 



16.7 

 13.0 

 20.2 



20.2 



21,6 

 12.0 



23.2 



24.26 



25.0 



24.9 



27.8 

 20.6 



