22 BULLETIN 352, U. S. DEPARTMENT OF AGRICULTURE. 
sulphate (40 per cent) on June 27. Of the beetles that fell from the 
tree, 318 were collected on a sheet and placed in a ventilated cage in 
the insectary. Five days later practically all of them, over 98 per 
cent, still showed no signs of life. 
Weaker dilutions of 40 per cent nicotine sulphate were tested on 
September 9 on beetles of the new brood. Pin-cherry trees were 
sprayed, because at this time the beetles were feeding on no other. 
The following strengths were used: One part of nicotine sulphate to 
800, 1,000, and 1,200 parts of water, respectively. Soap was added 
as in the first experiment at the rate of 2 pounds to 50 gallons of 
liquid. None of these strengths was effective, and none of them 
showed the immediate effects that followed spraying with a solution 
at the strength of 1 to 600. Many of the beetles hit with the sprays 
of the strengths of 1 to 800 and 1 to 1,000 became very sluggish and 
in 10 or 15 minutes appeared dead. Very few of those hit by the 1 
to 1,200 solution appeared injured at all. About 150 beetles were © 
collected from trees sprayed with each solution and placed in jars in 
the insectary. On the evening of September 10, 60 per cent of the 
beetles sprayed with the 1 to 800 solution, 68 per cent of those sprayed 
with the 1 to 1,000 solution, and 96 per cent of those sprayed with the 
1 to 1,200 solution were active and feeding. ; 
RESULTS FROM SPRAYING BY GROWERS. 
Immediately following the advent of the cherry leaf-beetle in the 
Lake Erie grape belt there was unusual spraying activity to check it. 
Arsenate of lead was used in most instances, but applications of lime- 
sulphur, Bordeaux mixture, nicotine sulphate, soap, and lime, used 
in various combinations and at various strengths, were also made. 
The results were various. 
Orchards in which arsenate of lead had been used at the rate of 5 
pounds to 50 gallons of water, with and without lime, were observed 
by the writers. In these orchards the trees were generally quite well 
protected, although few dead beetles were found on the ground under 
the trees. Where weaker solutions of poison were used the results 
were far from satisfactory in the orchards observed. The use of 
sweetened arsenate of lead was observed in only one orchard outside 
of the experimental plats, and in this instance it was entirely unsuc- 
cessful. The spray was applied immediately before a heavy rain, 
which washed it all off. | 
A number of combination sprays in which 40 per cent nicotine 
sulphate was used were successful. The nicotine sulphate was 
sometimes used at rates as strong as 1 to 400. The following is a 
typical effective mixture: Arsenate of lead, 3 pounds; 40 per cent 
nicotine sulphate, 1 pound; laundry soap, 2 bars; water, 50 gallons. 
