EXPERIMENT STATION BULLETINS. 263 



TABLE NO. 4. 



Sprayed with Bordeaux Mixture Every Twenty Days. 



Yield per acre of merchantable tubers 68.8 bu. 



Yield per acre of small tubers 15 bu. 



Total yield per acre 83.8 bu. 



Gross receipts per acre at 50 cents per bu $34 40 



Gross gain in dollars per acre by spraying 13 90 



Increase in yield per acre by spraying 27.8 bu. 



Number of sprayings 4 



Amount of lime used per acre 12 lbs. 



Amount of copper sulphate used per acre 10 lbs. 



Cost of lime per acre $0 05 



Cost of copper sulphate per acre 70 



Cost of application 2 12 



Total cost per acre of spraying $2 87 



Net gain per acre by spraying 11 03 



TABLE NO. 5. 



Sprayed loith Bordeaux Mixture Every Fifteen Days. 



Yield per acre of merchantable tubers 73.5 bu. 



Yield per acre of small tubers 15.8 bu. 



Total yield per acre 89.3 bu. 



Gross receipts per acre at 50 cents per bu $36 75 



Gross gain in dollars per acre by spraying 16 25 



Increase in yield per acre by spraying 32.5 bu. 



Number of sprayings 4 



Amount of lime used per acre 12 lbs. 



Amount of copper sulphate used per acre 10 lbs. 



Cost of lime $0 05 



Cost of copper sulphate 70 



Cost of application ; 2 12 



Total cost per acre of spraying $2 87 



Net gain per acre 13 38 



