CONTROL OF THE GRAPE-BERRY MOTH. 
23 
oil soap without resin (Plat VIII), were used. The difference in in- 
festation in these plats was so slight that it is not worthy of special 
consideration. Resin fish-oil soap solution spread rapidly and could 
be applied most easily. Arsenate of lead when used at the rate of 2\ 
pounds (powder) to 50 gallons of liquid (Plat VI) did not appear more 
effective than when used at the rate of \\ pounds to 50 gallons. The 
solution in which Bordeaux mixture was omitted (Plat VII) was 
practically as effective as any other, although slight burning followed 
its application. 
EXPERIMENT IN THE SOUTHWICK VINEYARD, NORTH EAST, PA., 1916. 
A plat of 28 rows, 9 rows to the acre, was chosen for experimental 
purposes in this vineyard. An unsprayed check of 8 rows was left 
in the middle of the plat. On one 
side were two sprayed plats of 6 
rows each, and on the other side 
two plats of 4 rows each. The rest 
of the vineyard section on either 
side of the experimental block, 
although sprayed for the grape 
rootworm by the owner, also served 
as a check. The arrangement of 
these plats is shown by the diagram 
(fig. 7). 
During the season of 1915 this 
section had been heavily infested, 
from 30 to 40 per cent, with a tendency for the infestation to be 
heaviest at the north end. 
/so&rs/ 
&£? 
nrsr 
s 
f/isr 
Fig. 7.— Diagram showing arrangement of ex- 
perimental plats in the vineyard of Mr. B. T. 
South wick, North East, Pa., 1916. The 
sprayed plats are marked with Roman numerals 
and the check plats with letters. (Original.) 
Table 14. — Spray mixtures used and methods and dates of application, Southwick vine- 
yard, North East, Pa., 1916. 
Date 
sprayed. 
Arsenate 
of lead 
(powder). 
Bordeaux mixture. 
Nicotine 
sulphate, 
40 per 
cent. 1 
Laundry 
soap. 
Water. 
Method of 
application. 
Plat No. 
Lime. 
Copper 
sulphate. 
I 
July 10, 24. 
do 
Pounds. 
U 
Pounds. 
3 
3 
3 
3 
Pounds. 
3 
3 
3 
3 
Pints. 
i 
4 
1 
1 
4 
1 
4 
Pounds. 
1 
1 
1 
1 
Gallons. 
50 
50 
50 
50 
"Trailers." 
II 
Do. 
Ill 
July 24. . . . 
July 10, 24. 
Do. 
IV 
first ap- 
plication. 
"Trailers' 5 
second. 
Last application only. 
