26 BULLETIN 837, U. S. DEPARTMENT OF AGRICULTURE. 
Spray schedule. — The combination of first and second spray appli- 
cations is adequate for control on the principal varieties of grapes 
grown in northern Ohio and when carefully applied leaves the fruit 
suitable for the basket market. 
Spray materials. — A combination of arsenate of lead powder 1J 
pounds to 50 gallons and resin fish-oil soap 1 pound to 50 gallons, in 
Bordeaux mixture or with stone lime 2 pounds to 50 gallons, may be 
used for spraying Concords and Catawbas. Copper sulphate should 
not be used in the above mixture for Ives variety. Arsenate of cal- 
cium, commercial powder, proved almost as efficient as arsenate of 
lead for grape-berry moth control. Dust mixtures do not adhere to 
the grape berries as well as liquid sprays but may be used on small 
home grape arbors if applied frequently. 
Spray residues.— -The grapes will be practically free from spray 
residue if the schedule recommended is used according to directions. 
Spray method. — The trailer method only was used, and a trailer 
provided with a short rod and two angle nozzles proved most satis- 
factory in most vineyards. 
RECOMMENDATIONS. 
When possible, vineyards should be placed in condition for winter 
at the end of the cultivation season in July and left without further 
cultivation until spring ; this practice is designed to increase the win- 
ter mortality of the grape-berry moth pupse. 
Number of spray applications. — For general practice for grape- 
berry moth control in northern Ohio two spray applications should 
be made. 
Time. — The first application should begin 3 to 5 days after grapes 
set and the second should begin when the grapes touch in the clusters. 
This second application will usually come 3 to 4 weeks after the first. 
Method. — Where the berry moth is a major pest the trailer method 
of spraying is the only one that will give complete control. 
Materials* — Arsenate of lead, at the rate of 1^ pounds of powder 
or 3 pounds of paste to 50 gallons, as the active killing agent, with 
resin fish-oil soap, at the rate of 1 pound to 50 gallons, for a spreader 
and adhesive, used either in Bordeaux mixture or with 2 pounds of 
freshly slaked lime to each 50 gallons, has proved the most consistent 
combination tried. Bordeaux mixture should not be used on the 
Ives variety of grapes in northern Ohio because of the danger of 
injury to the foliage. Amounts of material should be great enough 
to allow the covering of all clusters with a thin, smooth film of spray 
material. 
