Linseed Oil Bordeaux 
E. W. Berger, Entomologist State Plant Board 
THE MIXTURE 
Mr. President, Ladies and Gentlemen : 
In an attempt to solve the problem of 
a mixture that would serve effectively as 
a fungicide and insecticide, three per cent 
raw linseed oil was mixed with strong 
bordeaux (double strength and stronger). 
Such a mixture is easily made by simply 
stirring the oil into the bordeaux, or in 
case of small quantities shaking them to¬ 
gether in a closed vessel. 
Linseed oil was used because it was 
known that some water will mix with 
paint, which is a mixture of linseed oil 
and a pigment; and it was found that, in¬ 
versely, small quantities of oil would mix 
with bordeaux, this being practically a 
cold-water paint. The fact that linseed oil 
is a drying oil, i. e., hardens and forms a 
dry film over any surface to which it is ap¬ 
plied, furthermore suggested the possibil¬ 
ity that it might serve as a “sticker' to 
stick the bordeaux more or less firmly to 
the plants to which it is applied, and keep 
it from being so readily removed by the 
rains. 
EXPERIMENTS 
Two satsuma orange trees, six rose 
bushes, two persimmon trees, a fig tree, 
a grapevine, and the trunks and larger 
limbs of three peach trees, were sprayed 
with several strengths of bordeaux, into 
which three per cent raw linseed oil had 
been incorporated as indicated in the pre¬ 
ceding paragraphs. This was on August 
8, ii and 12, 1915. 
The object of the experiments was to 
determine what effect the mixture would 
have on San Jose scale infesting the 
peach trees, on purple scale and whitefly 
(Aleyrodes citri) infesting the satsumas, 
and on the foliage of the several trees and 
bushes sprayed. Its effect on the sooty 
mold, which always accompanies white- 
fly, and on a leaf fungus commonly found 
infecting leaves of fig trees, was also to* be 
determined, as well as the sticking* quali¬ 
ties of the mixture. 
results 
The effect of the mixture on the in¬ 
sects was not conclusive and it may be 
necessary to increase the amount of oil or 
add other oils in order to perfect its in¬ 
secticidal properties. 
The effect of the linseed oil as a “stick¬ 
er," however, stood out pre-eminently, 
the bordeaux remaining visible on the 
leaves and bark for five to six months and 
longer. That the results with the linseed 
oil as a sticker were not accidental was 
shown by several checks (2 rose bushes 
and a peach tree) that were sprayed at 
the same time with fresh bordeaux with¬ 
out the addition of the oil. When almost 
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