74 



PHYSIOLOGY OF NUTRITION 



Fig. 44. — Growth of oats with various fertilizers. O, without addition to the soil; KP 

 with addition of potassium and phosphoric acid; KPN, with addition of potassium, phosphoric 

 acid and potassium nitrate. (After P. Wagner.) Compare with Fig. 45- 



Fig. 45. — Growth of peas with various fertilizers. 0, without addition to the soil; KP, 

 with addition of potassium and phosphoric acid; KPN, with addition of potassium, phos- 

 phoric acid and potassium nitrate. (After P. Wagner.) Compare with Fig. 44. 



