New YorK AGRICULTURAL EXPERIMENT STATION. 17: 
quantity of bordeaux was prepared. A part of this was used for 
spraying the rows which were to receive bordeaux only; then paris 
green was added to the remainder and the rows which were to 
receive bordeaux with paris green were sprayed. The dates of 
spraying were June 29, July 6, July 20, August 7 and August 21. 
At the beginning of the experiment it was the intention to keep 
the bordeaux-only rows free from bugs by hand picking as in the 
experiment in 1904; but after one picking it was found that this 
could be much more easily accomplished by very thorougi spraying 
with bordeaux just after the bugs were hatched. In this minner 
the bugs were kept entirely under control so that they weve elimi- 
nated from the experiment.*! 
“In this experiment and also in the experiment with arsenite of soda, 
page 179 it was shown that bugs may be controlled with bordeaux mixture 
alone provided the spraying is done just after the bugs have hatched and 
very thoroughly. But for this fact this experiment could not have been 
carried through properly. After the first spraying of June 29 a few bugs 
remained alive and these were removed by hand picking July 3. On July 5, 
we were dismayed to find all of the plants swarming with young bugs. Of 
course it was to be expected that on the rows treated with paris green they 
would be poisoned before they could do harm; but on the rows sprayed with 
bordeaux alone they would surely injure the plants and thereby ruin the 
experiment. For the most part, the bugs were located among the small young 
leaves in the tops of new shoots. To have removed them by hand picking 
would have been a tedious operation, besides it could not well have been 
accomplished without considerable mutilation of the plants. In this emerg- 
ency we decided to try bordeaux mixture. Accordingly, the second spraying 
was made July 6, or about a week earlier than it would have been made had 
not this trouble with bugs arisen. The operator was instructed to give 
special attention to the new growth and to spray very thoroughly. Twenty- 
four hours after the spraying most of the bugs had disappeared on the 
“bordeaux-only”” rows as well as on those on which poison had been used. 
The bugs still in evidence appeared uneasy. Some were traveling on the 
ground under the plants. Practically all of them disappeared so that no harm 
was done to the plants and no further hand picking or other treatment for 
bugs was necessary. Whether the bugs were actually killed by the bordeaux 
could not be determined, but they certainly disappeared. 
Although this experiment was entirely successful we do not believe that 
farmers should attempt to control bugs by the use of bordeaux alone. The 
method is too expensive and requires too much care. To be successful the 
spraying must be done with extreme thoroughness and while the bugs are 
very small. Nevertheless the results have a direct bearing on practical 
potato spraying. They show that the bordeaux is not only a preventive of 
blight, but also an aid in the control of bugs and should be used with the 
poison whenever it is necessary to combat bugs. 
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