1911.1 



PUBLIC DOCUMENT — No. 31. 



41 



Average Yield per Acre (Pounds). 



The various potash salts used are employed in such quantities 

 as to furnish substantially equal actual potash to each plot. In 

 the case of the feldspar, which is very fine ground, the quan- 

 tity employed on Plot 8 furnishes the same amount of ])otash 

 as that supplied by the different potash salts. Plot KJ receives 

 the same amount as Plot 8, Plot 24 receives twice as much, 

 Plot 32 three times as much, and Plot 40 four times as much. 

 Particular attention is called to the fact that up to and includ- 

 ing 1908 the plots now receiving feldspar had been annually 

 receiving a potash salt which had given results indicating a 

 high degree of availability. It is believed that the crops on 

 these plots are still deriving considerable benefit from the re- 

 sidual potash applied in the earlier years of the experiment. 



The following points seem especially worthy of notice : — 



(1) The average yield of hay on all the potash plots exceeds 

 the average yield on the no-]">otash plots by only GOO pounds. 

 The average yield of rowen on the potash plots exceeds the 

 yield on the no-potash jdots by about 1,000 pounds. These 

 figures indicate that the grasses, timothy and redtop, which 

 make up the bulk of the first crop, are not dependent in very 

 high degree upon an application of potash, and the much larger 

 increase in the yield of rowen on the potash plots is clearly to be 

 attributed to the fact that clovers make up the greater part of 

 the rowen. 



(2) The kainit, while favorable to the grasses, such as tim- 

 othy and redtop, and therefore giving a first crop nearly equal 



