34 Maine Agricultural Experiment Station. 1918. 



Yield Per Acre in Xo Potash Experiment with Potatoes. 



1917. 







- 



Merchantable 





Culls 





Plot 



Amount of Pota=h 















Xo. 





















Cwt. 



Bbls. 



Bus. 



Cwt. 



Bbls. 



Bus. 





SERIES 1 

















755 



Xone 





131.0 



79.4 



218.4 



4.1 



2.5 



6.9 



756 



None 



+ Salt 



136.0 



82.4 



226.8 



4.6 



2.8 



7.7 



757 



3 per 



cent Potash 



135.3 



82.0 



225.5 



3.1 



1.9 



5.2 



758 



5 per 



cent Potash 



130.8 



79.3 



218.8 



2.6 



1.6 



4.4 



759 



7 per 

 SERIES 2 



cent Potash 





84.0 



231.0 



2.5 



1.5 



4.1 



760 



Xone 





139.5 



84.6 



232.7 



4.0 



2.4 



6.6 



761 



Xone 



- Sa't 



144.0 



87.3 



240.1 



3.6 



2.2 



6.1 



762 



3 per 



cent Potash 



149.3 



90.5 



248.9 



3.5 



2.1 



5.8 



763 



5 per 



cent Potash 



157.4 



95.4 



262.4 



3.8 



2.3 



6.3 



764 



7 per 



cent Potash 



160.4 



97.2 



267.3 



3.8 



2.3 



6.3 



The yields for the 3 years 5 series are summarized in the 

 table that follows. 



No Potash Experiment with Potatoes. 1915-1916-1917. Yield 

 in Hundredzveight Per Acre. 



1915 1916 1917 Average 



Amount of Potash 



Series 1 Series 2* Series 1 Series 2 



None 



182 



172 



198 



131 



140 



156 



Xone - Salt 





193 



200 



136 



144 



158 



3 per cent Potash 



191 



254 



193 



135 



150 



182 



5 per cent Potash 



191 



254 



191 



131 



157 



183 



8 per cent Pota-h 



198 



244 



226 



139 



160 



18a 



-In this series the potatoes followed potatoes. Omitted from average. 



From the results of these 4 trials in 3 seasons on sod land 

 the following tentative conclusions may be drawn: The addition 

 of 300 pounds of common salt per acre made a small but uniform 

 increase in yield. The addition of as little as 45 pounds (T500 

 pounds of 3 per cent goods) per acre of potash uniformily in- 

 creased the vield of potatoes and profitably. That on Aroostook 

 Farm soil nothing was gained by a larger application. That 

 good yields were obtained without any potash. It will also be 

 noted that in the soil test experiment (page 17) that nitrogen 

 and not potash seems to be the limiting factor in potato pro- 

 duction on Aroostook Farm. 



