FLORIDA STATE HORTICULTURAL SOCIETY. 
79 
Discussion on Citrus Insects and Insecticides. 
C. F. A. Bielby —I would like to ask Prof. Weber if he 
has given the whole formula for the rosin wash? 
Prof. Webber —Yes, I have given the whole formula which 
in our tests with different strengths we found could be re¬ 
duced to 150 gallons and yet be very effective for the White 
fly, and will probably also prove effective for the six-spotted 
mite, scale insects and plant lice. 
Lyman Phelps —Have you tried it on the Black scale? 
Prof. Webber —It has been tried on the Black scale in Cal¬ 
ifornia, I believe, but I have had no opportunity to make 
such tests. 
Mr. Phelps —I would say that Prof. Mead and I tried it 
last year on the Black scale and it did not work. 
Prof. Webber —I was not aware that the Black scale oc¬ 
curred in Florida. 
Mr. Phelps —We have had it at Orlando and Oviedo. 
Prof. Webber —I have not observed it in Florida yei. 
Mr. Bielby —I would like to ask the Professor if I have the 
formula correct, as follows: Twenty pounds of rosin, 4 2-7 
pounds of caustic soda (98 per cent.), and 3 pinis of fish oil. 
Put in a kettle with 15 gallons of water and boil until the 
rosin is thoroughly dissolved; then dilute with cold water. Is 
this com ci? 
Prof. Webber— Yes, that is correct. I would like to add 
further that- the Red scale ( Aspidiotus Ficus), which is prob¬ 
ably the worst, scale pest ot the orange in Florida, other than 
the White fly, may probably be controlled by the rosin 
washes. The soap or wash when made will keep for an indef¬ 
inite period. The samples exhibited here today were pre¬ 
pared last Saturday, and are as good now as then, and will be 
as good a year hence. 
A. L. Duncan —I wish to say that I have us. d i his rosin 
and fish oil wash for about three years extensively. The form¬ 
ula came to me from California, and I have tried it at all sea¬ 
sons of the year. I have been preparing it just the way the 
Professor gives, excepting that I use pounds of rosin and 
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