SPRAY MATERIALS TO PREVENT DISEASE 



307 



Lime-sulfur. — This preparation is used abundantly in the control 

 of San Jose" scale, either as a winter spray or as a summer spray. 

 The spores of fungous diseases are largely killed when this spray is 

 applied. If orchard trees, for example, are sprayed with lime- 

 sulfur during the winter the spores with which the spray comes in 

 contact are killed. This aids materially in the reduction of the 

 disease during the following growing season. 



There are several forms of lime-sulfur prepared. The home 

 boiled concentrated lime-sulfur (Fig. 215), the commercial lime- 

 sulfur, the self-boiled lime-sulfur and the commercial dry powder. 



Fig. 215. — Home boiled lime-sulfur may be prepared as shown or may be boiled by a steam 

 pipe leading into a barrel from a boiler. (Indiana Station.) 



For spraying on a large scale the home made lime-sulfur may be 

 prepared as follows: Use 38 pounds of fresh unslaked lime, 40 

 pounds of clean rolled sulfur powdered, and 50 gallons of water. 

 Make a paste of the sulfur, using about 10 gallons of hot water. 

 Then add the lime and let it slake. Add more hot water as neces- 

 sary to prevent drying or lumping. When the lime has all slaked 

 add the balance of the water to make the 50 gallons and boil, 

 stirring thoroughly while boiling, for one hour (Fig. 215). As the 

 water boils away more should be added to maintain the quantity. 



A good method of boiling is to have the water in a barrel or tank 

 and heat by means of a hose or steam pipe from a small boiler. A 



