448 INVESTIGATION BY CULTURE EXPERIMENTS 



TABLE 83. OHIO EXPERIMENTS: THREE-YEAR ROTATION 

 Average Records per Acre for Five Rotations, 1894 to 1908 



1 The standard forms include both dried blood (usually 50 Ib.) and sodium 

 nitrate (usually 200 Ib.), acid phosphate, and potassium chlorid, the applications 

 being divided, in most cases, between the potatoes and wheat. 



hay, $6.00 a ton ; nitrogen, 15 cents a pound ; phosphorus, 12 cents 

 (10 cents in raw bone, slag, and tankage) ; and potassium, 6 cents. 

 The price of potatoes varies greatly, and for that reason the figures 



