232 Report of the Botanical Department of the 



Diagram I. — Showing Location and Yields of Test Rows in the 



Andover Experiment. 



Double-sprayed five times . 



Single-sprayed five times. 



149.7 bu. per a. 



Check. 



Single-sprayed five times. 



157.3 bu. per a. 



157.3 bu. per a. 

 177 . 1 bu. per a. 



195 . 8 bu. per a. 



Double-sprayed five times . 



168.9 bu. per a. 



Average yield of double-sprayed rows, 159.3 bu. per acre. 



Average yield of single-sprayed rows, 176.G bu. per acre. 



Average yield of check rows, 167.2 bu. per acre. 



Gain from single-spraying, 9.4 bu. per acre. 



Loss from double-spraying, 7.9 bu. per acre. 



Witb potatoes selling at 55 cts. per bushel, 9.4 bu. would have 

 a value of $5.17. Subtracting from this the expense of spraying, 

 $2.76 per acre, there remains $2.41 per acre as the net profit from 

 single-spraying five times. Computed in a similar manner the 

 loss from double-spraying five times was $9.86 per acre. 



