38 BULLETIN 550, U. S. DEPARTMENT OF AGRICULTURE. 
with "set nozzles" instead of with "trailers/' furnishes on the aver- 
age only a partially satisfactory measure, while complete substitution 
of "set nozzles" for "trailers" is entirely unsatisfactory. 
Spray Combination* 
A combination of sprays may be made, to control, besides the berry 
moth, practically all other important enemies of the grape in this 
region — the grape rootworm, the grape leafhopper, and the powdery 
mildew. These spraying recommendations for the control of enemies 
of the grape other than the grape-berry moth, are based on recommen- 
dations of other investigators, 1 and were employed incidentally in 
connection with the berry-moth experiments. 
The time of the first spray application for berry moth, just after 
the grape blossoms fall, during the seasons of 1914, 1915, and 1916, 
has been from 2 to 4 days before the appearance of the root-worm 
beetles. Without change of time or mixture this application is 
effective against the rootworm also. If this application is intended 
as rootworm control also, care should be taken to cover the upper 
surface of the foliage, for unless extra attention is given to this it 
is apt to be done less effectively with ••trailers" than with "set 
nozzles. 7 ' In exceptional instances an extra application for root- 
worm control may be necessary. This combination must not be 
attempted if it is desired to add molasses or sugar to the rootworm 
spray, as mixtures containing sugar are very soluble and wash off 
the vines readily. Furthermore; a combination of sugar with Bor- 
deaux mixture is apt to burn foliage. 
The second berry-moth spray, applied when the berries are just 
touching, may be made effective also against the grape leafhopper 
by the addition of nicotine sulphate (40 per cent) at the rate of 1-1,600 
(1 pint to 50 gallons.) 
By the addition of Bordeaux mixture in these two applications, 
powdery mildew also can be controlled. These two applications of 
Bordeaux will be useful against black rot and downy mildew also, 
where these occur, although an additional earlier spray will be 
necessary for the control of these diseases. 
Cost. 
The cost of spraying material and labor required to control the 
grape-berry moth, if applied to control the berry moth alone, is 
about $5 per acre. In computing this cost it is assumed that an 
average of 6 acres are sprayed per day and that 150 gallons of liquid 
are applied per acre. This average may not be maintained if the 
water supply is inconveniently situated and the spraying machinery 
is not kept in condition, but delays due to these sources are not nor- 
i See Quaintance and Sk )ar (12), Johnson and Hamniar (13), Johnson (17), and Hartzell (IS). 
