204 BACTERIA IN RELATION TO PLANT DISEASES. 
FORMULA. 
Copper Sulphate. 
Dissolve in hot water, or by suspending the 
crystals in a sack in the top of the cold water. 
This is best done over night. It is convenient 
to make a strong solution (1 or 2 pounds per 
gallon) and dilute as needed. 
Ammoniacal Solution of Copper Carbonate. 
Use 5 ounces of copper carbonate, 3 pints or 
less of strong ammonia water (26° B.), 7. e., 
just enough to bring the copper carbonate 
into solution, and 50 gallons of water. The 
copper carbonate must be wet with water first 
and then stirred into the ammonia after the 
latter has been diluted with 5 or 6 volumes of 
water. Add always a slight excess of the 
copper carbonate and use only the supernatant 
clear liquid. 
Used on foliage and fruit when Bordeaux 
mixture would be unsightly. Apply frequently 
in case of rainy weather. 
Bordeaux Mixture. 
There are various formule in which the first 
figure represents pounds of copper sulphate, 
the second figure pounds of stone lime and the 
third gallons of water. The 6:4: 50 is the 
usual combination and sticks better than the 
4:6:50. It also sprays easier. For sensitive 
plants 4 : 4 :50 may be used or 4:5 : 50. 
The lime must be of good quality and fresh 
slaked. Air slaked lime must not be used, 
neither should concentrated solutions be mixed, 
nor hot solutions. Divide the 50 gallons of 
water into two equal parts. Dissolve the cop- 
per sulphate in one part. This is usually done 
over night. Slake the lime with a portion of 
the other part, adding the water slowly, then 
add the remainder of the water when the lime 
has ceased to be lumpy. When ready to spray, 
stir thoroughly to obtain an even mixture of 
the lime and water and pour the two fluids 
together through a strainer tied across the top 
of a clean barrel. ‘The two streams should 
blend as they fall to insure a good product, 
the essential features of which are alkalinity 
and a fine grain insuring suspension in the fluid 
long enough to permit of the spraying, which 
should be undertaken at once. Concentrated 
solutions give a coarse precipitate which settles 
quickly. The mixture should be absolutely 
free from sawdust, sticks, straws, chaff, wool, 
fragments of leaves or any similar substances. 
Otherwise, vexatious delays are likely to arise 
from clogging of the nozzle. In spraying use 
a good force pump. A Vermorel nozzle affords 
a well distributed fine spray. For dilute 
Bordeaux reduce the copper sulphate one-half, 
or double the volume of water. This may be 
sprayed upon soils to check the damping off 
of seedlings. 
Stock solutions of the two fluids may be 
prepared in advance and will keep indefinitely. 
They are conveniently kept in tubs or half 
barrels closely covered, the lime always under 
the required volume of water, and the copper 
sulphate in strong solution. When needed one 
then has only to measure out a portion of the 
copper sulphate water, dilute it to the required 
volume, stir up the settled lime very thoroughly, 
dip out the required volume of the milk of lime 
quickly, and pour the two fluids together, as 
already described. 
An acid Bordeaux should never be sprayed 
upon plants. The following are tests for acid 
Bordeaux: (1) A film of metalic copper deposited 
on polished iron or steel when plunged into 
the mixture; (2) a purplish red reaction on 
putting into the Bordeaux a drop of a water 
solution of yellow prussiate of potash (1 to 10). 
If either of these reactions is obtained more 
lime must be added. It is best to avoid dry 
Bordeaux and similar commercial substitutes. 
Resin Bordeaux. 
This is made by adding to each 50 gallons 
of Bordeaux a clear liquid made by boiling 
for one hour 1 pound resin and 0.5 pounds 
crystals sal soda in 0.5 gallon water. Another 
way of making it is to melt 5 pounds of resin 
in 1 pint of fish oil, slowly add 1 pound of 
potash lye, stirring, and taking care that it 
does not become too hot and boil over. Then 
add 2 gallons of water and continue boiling 
for an hour. Finally add slowly with stirring 
an additional 3 gallons of water. ‘The finished 
product should dissolve readily in cold water. 
Two gallons of this soap is added to each 50 
gallons of the finished Bordeaux. Resin fish 
oil soap may also be bought and may be added 
to Bordeaux at the rate of 5 pounds per 50 
gallons. 
Soda Bordeaux. 
Soda lye 1 pound; copper sulphate 3 pounds; 
lime 5 ounces; water 50 gallons. 
Arsenate of Lead. 
Three pounds to 50 gallons of water, mixed 
thoroughly with a little water first. 
