EXPERIMENTS WITH FUNGICIDES ON POTATOES. 5 1 



Vermorel nozzles and the plots were gone over twice in oppo- 

 site directions. In the three other sprayings, double Vermorel 

 nozzles were used. Insecticides were used in each application, 

 although in the first and fourth sprayings they were not needed. 

 With the pump used, Bordeaux mixture will be forced 

 through double Vermorel nozzles at the rate of about one bar- 

 rel to the acre. In practical work on a large scale a spraying 

 outfit with power pump can be advantageously used. In these 

 experiments a hand pump was chosen, as the pressure was then 

 under complete control. As it was desired to take every pre- 

 caution for thorough spraying, two men were on the cart, one 

 to pump, the other to drive and watch that the nozzles did not 

 get stopped. 



ARRANGEMENT OF PEOTS. 



The field selected for the test of the commercial Bordeaux 

 mixtures was the same as that used for insecticides (See Bul- 

 letin 68). This field was planted with Green Mountain potatoes 

 late in April, the rows running east and west. There were 224 

 rows about 30 rods long running across the field, and in addition 

 about 20 shorter rows at the north and ten at the south ends 

 of the field. The arrangement of the plots and their treatment 

 is shown in the following plan : 



Each plot for the prepared Bordeaux mixture consisted of 18 

 rows about 30 rods long. The rows ran east and west. Row 

 1, at north end. Unsprayed rows were left at each end of field. 



1 to 16 Bordeaux mixture, 1 barrel to acre 



17 to 32 Bowker's Boxal, 5 pounds to acre 



33 to 48 Bowker's Boxal, 10 pounds to acre 



49 to 64 Adler's Bordeaux, 1 gallon to acre 



65 to 80 Bordeaux mixture, 1 barrel to acre 



81 to 96 Blanchard's Bordeaux, Lion brand, 1 gal. to acre 



97 to 224 Bordeaux mixture 



Dates of applications : 



July 11. Bloom just beginning, 



lulv 21. 



July 27. In full bloom. 



Aug. 10. Still in bloom. 

 The fungicides were applied under the personal supervision of 

 the writer, and the fields were visited and full notes taken at 

 frequent intervals. 



