26 



MAINE STATE COLLEGE 



TABLE VI. 





Yield per acre of air-dry 

 crops. 





">-.m 



O >v 



Hod 



Total increase 

 of yield over 

 plots not fertil- 

 ized. 



Annual in- 

 crease of yield 

 over plots not 

 fertilized. 





14,050 

 15,742 

 19,006 

 16,820 



21,381 



1,690 

 4,956 

 2,770 



7,3.31 





Fertilizer supplying only phosphoric acid 



Fertilizer supplying phosphoric acid and potash 



211 



619- 

 34& 



Fertilizer supplying nitrogen, phosphoric acid and 



9l6 







While there is certainly an increase of crop from every combina- 

 tion of ingredients used, there is no doubt of the superior influence 

 of the mixture of the three. 



THE RELATIVE EFFECT OF DIFFERENT AMOUNTS OF FERTILIZER. 



One of the important considerations pertaining to the use of com- 

 mercial fertilizers is the quantity to be applied. In these experi- 

 ments the amount of complete fertilizer applied per acre on one set 

 of three plots has been at the rate of 360 pounds per acre, on 

 another set 595 pounds and on a third set 830 pounds. The results 

 show that the increase of production has been almost directly pro- 

 portional to the amount of fertilizer used. 



TABLE VII. 



■ss 



H o a.S 





Plots receiving no fertilizer (average of 6) 

 riots receiving 360 lbs. fertilizer per acre 

 Plots receiving 595 lbs. fertilizer per acre . 

 Plots receiving 830 lbs. fertilizer per acre . 



14,050 

 17,738 

 19,957 

 23,243 



3,688 

 5,907 

 9,193 



2.05 

 1.95 

 2.25 



