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WISCONSIN STATE HORTICULTURAL SOCIETY.
and the amount of spray used will vary with the leaf develop-
ment of the trees.
After the materials are at hand the next thing to consider is
the proper utensils which are to be used in compounding the
mixture. If only a small amount of spray material is to be made
we will need three 50 gal. barrels, 2 large wooden pails, such as
candy pails, and a few gunny bags. If the mixture is to be
made on a large scale, as for a commercial orchard, larger and
more pretentious utensils will be needed. The tanks should be
elevated so that the materials will not have to be lifted bitt
may flow by means of gravity. In making Bordeaux Mixture
use only wooden or earthen utensils as the Copper Sulphate
corrodes metals.
There are numerous formulae for the manufacture of Bor-
deaux Mixture and they will vary as the use to which the mix-
ture is to be put. The formula generally used and the one we
will use as an example is the 4-4-50 formula. It must be re-
membered, however, that the ingredients of Bordeaux Mixture
unite in certain definite proportions and that the proportions
are designated by the formulae which should always be followed
closely.
In making small amounts of Bordeaux Mixture the quantities
of materials called for in the formula are weighed out and the
Copper Sulphate is dissolved in water. The lime is slaked and
the two then diluted each to 25 gals. They are then poured
simultaneously through a gunny bag into a barrel. The result-
ing mixture is Bordeaux.
If any quantity of mixture is to be made, however, stock
solutions are resorted to. Certain definite amounts of materials
are weighed out and made up to certain volumes. As 50 lbs.
Copper Sulphate made up to 50 gal. water and 50 gal. lime
also made up to 50 gal. of water. Then 1 gal. of the stock solu-
tion contains 1 lb. of the material. In dissolving, the 50 lbs.
are tied in a gunny bag and suspended at the top of a bar-
rel of water. As the Copper Sulphate is heavier than water it
sinks to the bottom as it dissolves and the water around the bag
is thus always in an unsaturated state. The lime is slaked in
a slaking box as in the shallow box it is easier to handle than
when in a barrel. The lime should have enough water on it
to keep it from burning but not enough to "drown" it. If
lime burns or "drowns" all of it does not slake and the stock
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