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ALBANY NURSERIES, Incorporated 
It is then ready for use. Considerable trouble has frequently been exper- 
ienced in preparing the bordeaux mixture. Care should be taken that the lime 
is of good quality and well burned, and has not been air slacked. Where 
small amounts of lime are slacked it is advisable to use hot water. The lime 
should not be allowed to become dry in slacking, neither should it become 
entirely submerged in water. Lime slacks best when supplied with just 
enough water to develop a large amount of heat, which renders the process 
active. If the amount of lime is insufficient, there is danger of burning tender 
foliage. In order to obviate this the mixture can be tested with a knife blade 
or with ferro-cyanide of potassium (1 ounce to 5 or 6 ounces of water.) If 
the amount of lime is insufficient, copper will be deposited on the knife blade 
while a deep brownish red color will be imparted to the mixture when ferro- 
cyanide of potassium is added. Lime should be added until neither reaction 
occurs. A slight excess of lime, however is desirable. • 
The bordeaux mixture is best when first prepared. Stock solution of lime 
and copper can be made and mixed when required. 
For summer spray, use only half strength, 3 pounds of copper sulphate 
instead of 6 pounds. 
SPRAY NO. 7 (FOR ROSE MILDEW.) 
1 ounce potassium sulphide. 
2 to 3 gallons of water. 
Dissolve the potassium sulphide in water. 
