86 
THE NATIONAL NURSERYMAN 
THE HOW OF BORDEAUX MIXTURE 
Copper sulfate 4 lbs., stone lime or hydrated lime 4 lbs., 
water 50 gals. Bordeaux is the fungicide most generally 
used. The strength varies according to the plant to be 
sprayed. The formula given above is the strength usually 
recommended. When a different strength is necessary, the 
formula is given under the disease. Stock mixtures of 
copper sulfate and lime are desirable. They are prepared 
in the following manner: 
Copper-Sulfate 
Dissolve the required amount of copper sulfate in water in 
the proportion of one pound to one gallon several hours before 
the solution is needed; suspend the copper sulfate crystals in 
a sack near the top of the water. A solution of copper sulfate 
is heavier than water. As soon, then, as the crystals begin to 
dissolve the solution will sink, bringing water again in contact 
with the crystals. In this way, the crystals will dissolve 
much sooner than if placed in the bottom of the barrel of 
water. In case large quantities of stock solution are needed, 
two pounds of copper sulfate may be dissolved in one gallon 
of water. 
Lime 
Slake the required amount of lime in a tub or trough. 
Add the water slowly at first, so that the lime crumbles into a 
fine powder. If small quantities of lime are used, hot water 
is preferred. When completely slaked or entirely powdered 
add more water. When the lime has slaked suflfieiently, add 
water to bring it to a thick milk or to a certain number of 
gallons. The amount required for each tank of spray mix¬ 
ture can be secured approximately from this stock mixture 
which should not be allowed to dry out. Hydrated or pre¬ 
pared lime of good quality may be substituted for the stone 
lime. Place the required amount in the barrel or tank and 
add water. No slaking is required. Do not use air-slaked 
lime. 
To Make Bordeaux 
Take five gallons of stock solution of copper sulfate for 
every fifty gallons of Bordeaux required. Pour this into the 
tank. Add water until the tank is about two-thirds full. 
From the stock lime mixture add the required amount. Stir 
the mixture, add water to make 50 gallons. Experiment 
stations often recommend the diluting of both the copper 
sulfate solution and the lime mixture to one-half the required 
amount before pouring together. This is not necessary, and 
is often impracticable for commercial work. It is preferable 
to dilute the copper sulfate solution. Never pour together 
the strong stock mixtures and dilute afterward. Bordeaux 
mixture of other strengths as recommended is made in the 
same way, except that the amounts of copper sulfate and lime 
are varied according to the requirements. 
The Ferro-Cyanide Test 
It is not necessary to weight the lime in making Bordeaux 
mixture, for a simple test can be used to determine when 
enough of a stock lime mixture has been added. Dissolve an 
ounce of yellow prussiate of potash in a pint of water and 
label it “poison.” Cut a V-shaped slit in one side of the cork 
so that the liquid may be poured out in drops. Add the lime 
mixture to the diluted copper sulfate solution until the ferro- 
cyanide test solution will not turn brown when dropped from 
the bottle into the mixture. It is always best to add a slight 
excess of lime. 
THE HOW OF SULPHUR SPRAYS 
Concentrated Lime-Sulfur 
Concentrated lime-sulfur solutions may be purchased from 
the manufacturers, of which there are now a large number 
making a good product, or they may be prepared by the 
grower himself. The following directions, given by J. P. 
Stewart, are taken from Pennsylvania Bulletin No. 99: 
50 lbs. best stone lime (90-95% calcium oxide). 
100 lbs. sulfur (powdered commercial 99^^% pure). 
Water to make 50 to 55 gallons total product. 
• Put 10 gallons of water in kettle and start fire. Place lime 
in kettle. After slaking is well started add the dry sulfur and 
mix thoroughly, adding water enough to maintain a thin 
paste, which requires about 5 gallons. After slaking and 
mixing are completed, add water to make about 50 gallons; 
bring to a boil and stir until the sulfury scum practically 
disappears. Then add water to make about 60 gallons and 
boil down to 50 or 55 gallons. The material should be kept 
well stirred, especially during the early stages of the process. 
The time of boiling should be until the sulfur granules are 
evidently dissolved, generally 40 to 60 minutes. Pour or 
strain the clear liquid into a barrel or other storage vessel that 
can be completely filled and corked, or cut off air contact with 
a thin layer of paraffin or any other heavy oil; this prevents 
formation of crystals. 
When ready for use, test the concentrate with a Beaume 
leter and dilute according to 
the following table 
Concentrate 
testing degrees 
Beaum6 
Dilute for 
peach leaf-curl 
trees dormant 
Dilute for 
apple, pear, cherry 
summer spray 
35 
I-43K 
34 
I-I6 
1-42 K 
33 
i-i 5}4 
I-41 
32 
1-15 
1-40 
31 
1-14K 
1-39 
30 
1-14 
i- 37 >^ 
29 
1-13K 
1-36 
28 
1-13 
1-35 
27 
1 - 12^2 
i- 33 >^ 
26 
1-12 
1-32K 
25 
I-II 
1-31 
Arsenate of lead may be added to the diluted concentrate 
at the rate of two to three pounds to 50 gallons. Do not use 
paris green, arsenite of lime, or arsenite of soda with lime- 
sulfur. 
Self-Boiled Lime-Sulfur 
This is not a boiled solution, as might be inferred from the 
name. It is prepared by placing in a barrel eight lbs. best 
stone lime, to which is added a small quantity of cold water to 
start it slaking. Eight pounds of sulfur worked through a 
sieve to break up the lumps is then added slowly to the slaking 
lime, which is kept from burning by the addition of just 
enough cold water so as not to drown it. The slaking mixture 
