110 REPoRt OF THE BOTANICAL DEPARTMENT OF THE 
not have occurred in the present case had the plants been givem 
a fifth spraying and the frost delayed so that the plants might 
have completed their growth. 
There was no loss from rot on either sprayed or unsprayed rows.. 
The gain on the sprayed rows seems to have been due almost 
wholly to the prolonged growth of the plants and this was the 
consequence of their having been protected against the ravages: 
of late blight. There was no early blight and no damage done 
by flea-beetles. ‘ 
The items of expense for spraying 26 acres four times are as: 
follows: 
601 pounds copper sulphate, at 6C............5..... $36 06 
Bou "ponds? lime;s"at Less Ahn. es SE Vento 2 89 
80-hours:labor'for teams 'at 1he@x6 cs ee See 12 00: 
140:hours labor for-man, atil5c. cs)... 25.2. 2s See 21 00 
57 pounds white arsenic (including cost of sal soda 
and the expense of preparation), at 10c............ 5 TO 
Wear on sprayer at 5c per acre for each application.. 5 20 
TPOta Ls crscane ee wrete anced othe sn vite PAGE a ee eee ee $82, 85 
The total cost of spraying per acre was $3.19 and the average 
cost per acre for each application 80 cents. The market price 
of potatoes at Gainesville at the time the test rows were dug was. 
43 cents per bushel of 62 pounds. | 
THE WEST HENRIETTA EXPERIMENT, 
This experiment was made by Robert Dunn at West Hen- 
rietta, about nine miles south of Rochester. Twelve acres of 
potatoes were sprayed eight times on the following dates: July 
25, August 2, 9, 16, 23 and 30 and September 6 and 15. Three 
rows 1,075 feet long, about the middle of the field, were left 
unsprayed. 
The spraying was done with a two-horse, six-row power sprayer 
made by E. C. Brown & Co., Rochester, N. Y. This sprayer has. 
one nozzle per row and the pumping is done automatically with 
power obtained from the wheels. (See Plate VIII, fig. 1.) The 
bordeaux used was made according to the formula: Seven 
pounds of copper sulphate, six pounds of lime and 55 gallons 
of water. Paris green was used with the bordeaux only in the 
