162 REPORT OF THE BoraNICAL “DEPARTMENT OF THE 
and Plate VI.) The total expense of spraying was $21.50. Three 
rows 850 feet long were left unsprayed. 
The middle unsprayed row yielded 365 pounds or 103 bushels 
54 pounds per acre, while the second sprayed row (only two rows 
between) yielded 508 pounds or 144 bushels 37 pounds per acre, 
which makes the gain due to spraying 40 bushels 43 pounds per 
acre. 
Bugs were not troublesome. The few that appeared on the 
unsprayed rows were removed by hand picking so that they did 
no harm. On the sprayed rows they were poisoned with arsenite 
of soda applied with the bordeaux. There was no rot. The 
unsprayed rows were severely attacked by late blight and died 
from seven to ten days earlier than those sprayed. Price of 
potatoes at digging time, 40 cents. 
EXPERIMENT NO. 25. 
This experiment, also, was conducted by J. V. Salisbury & 
Sons, on their farm east of Phelps. Fifteen acres of potatoes 
were sprayed five times with the same sprayer used in Experi- 
ment No. 24. Three rows 1140 feet long were left unsprayed. 
The unsprayed rows and adjacent sprayed rows were of the 
varieties Rural New Yorker No. 2 and Carman No. 3 mixed. 
Accurate record of the expense of spraying in this field was not 
kept, but judging from accounts kept in 1903 and in Experiment 
No. 24 the expense was probably 80 cents per acre for each spray- 
ing or $60 for spraying 15 acres five times. 3 
The middle uwnsprayed row yielded 593 pounds, or at the rate 
of 125 bushels 49 pounds per acre, and the yield of the second 
sprayed row on one side of the unsprayed was 907 pounds or 192 
bushels 26 pounds per acre. Thus the gain from spraying was 
66 bushels 87 pounds per acre, or nearly 53 per ct. 
The unsprayed rows were treated once with paris green, which 
was sufficient to contro] bugs; while on the sprayed rows arsenite 
of soda was used with the bordeaux. There was no rot on sprayed 
or unspraved rows. Price of potatoes 40 cents. | 
The soil in the western part of this field was clay loam while 
in the eastern portion it was quite sandy. Consequently, blight 
was much more virulent toward the west. Here, the sprayed 
rows outlived the unsprayed by at least two weeks. Practically 
