38 



The Bulletin. 



Table III— 



AMSRAGE RESULTS FOR SEVEN 



Number 



of 



Plat. 



5»-18-8 



1>-14-12 



2'-15-13 



Fertilizer Application per Acre. 



a 

 o 



K. 



so- 



0^ 



Unfcrtilized= 0=» 



69.2 pounds 13% blood= N= 



300 pounds 14% acid pho9phate=-- 2P= 



22.5 pounds 20% manure salt= -K== 



69. 2 pounds 13% blood= N= | 9 



4.50 pounds 14% acid phosphate=.. 3P= ' 



22.5 pounds 20% manure salt= - - K^ I 



2 •- 



C a> 



X & 



ii 



42 



63 



C 



o 



- o 



4.5 



.4.5 



Yield in Bushels 



of Shelled Corn 



per Acre. 



1903 1904 



1906 



Checks for plat 8, Field A, and plat lO^, Field B. have been obtained from plats 4 and 11, and .5' and 14^ 

 respectively. It has been assumed that there is a uniform increase or decrease in the natural fertility between 



THE EFFECT OF VARYING QUANTITIES OF PHOSPHORIC ACID. 



Tlie above experiments in Table III ^vcre planned to show the 

 efTec't 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 represented by 75 pounds of 14 per cent acid phosphate and 

 equivalent to 3^ per cent phosphoric acid in the fertilizer mixture. 

 On two ]>lats were applied two and three times the normal quan- 

 tities of phosphoric acid represented by 300 and 450 pounds of 14 



TABLE IV— RESULTS OF FERTILIZER EXPERIMENTS WITH CORN ON 



RESULTS IN FIELD B 



Number 



of 



Plat. 



3> 



Fertilizer Application per Acre. 



69.2 pounds 13% blood= N= i 



l.'iO pounds 14% acid phosphate= _ ^^^ I 



11.2 pounds 20% manure 8alt= HK= 1 



