234 Report of the Botanical Department of the 



the dryden experiment. 



Conducted bj D. R. Trapp, Dryden, N. Y. The experiment 

 included three fields containing eight acres of potatoes. Five ap- 

 plications of bordeaux were made with a two-horse, four-row 

 " Iron Age " sprayer carrying two nozzles per row. Bordeaux of 

 the Y-9-55 formula was used in the first three sprayings while in 

 the last two sprayings 8-12-55 bordeaux was used. In the first 

 two sprayings paris green was added to the bordeaux at the rate 

 of three pounds to 55 gallons for the control of bugs. In one 

 field a strip of three unsprayed rows was left for a check. These 

 rows were dusted twice with paris green and flour, which gave 

 good protection against bugs. The test rows were of the variety 

 Gold Coin. They suffered severely from tip bum and flea beetles, 

 but were unaffected by blight. Neither the tip burn nor the flea 

 beetles were materially checked by spraying. There was very 

 little contrast l>etween sprayed and unsprayed rows. 



The expense of spraying was as follows: 



222 lbs. copper sulphate (@ 5 cts $11 10 



300 lbs. lime 1 90 



43 lbs. paris green @ 20 cts 8 60 



40 hrs. labor for man and team @ 40 cts 16 00 



Wear on sprayer 5 00 



Total $42 60 



Expense of spraying one acre five times, $5.32. 

 Expense of spraying one acre once, $1.07. 

 The test rows (300 ft. x 32 in.) yielded as follows: 

 East sprayed row, 210 lbs.= 190.6 bu. per acre. 

 West sprayed row, 206 Ibs.^ 187 bu. per acre. 

 Average yield of sprayed rows, 188.8 bu. per acre. 

 Middle check row, 183 Ibs.^ 166.1 bu. per acre. 

 Gain from spraying, 22.7 bu. per acre. 



Potatoes being worth 55 cents per bushel at time of digging, the 

 spraying resulted in a net profit of $7.16 per acre. 



