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Rosin. The spray mixtures containing rosin are useful 

 in combating the unarnioured scales (Saissetia, Coccus), and 

 other scale insects and thrips ; but is of most value in dry 

 seasons and when the young scales are most abundant. 

 Rosin is applied in combination with other materials as a 

 spray or wash. 



Rosin compound is made of : 



Powdered rosin 4 ft>. 



Powdered washing soda 3 lb. 



This quantity is sufficient to make 30 gallons of wash. 

 It is prepared by mixing the constituents thoroughly, and 

 dissolving by boiling, in 1 gallon of water, in a vessel with 

 a capacity of at least 5 gallons. Water is slowly added 

 to make 5 gallons, the mixture being kept boiling. This is 

 the stock solution ; when cold it should be of a clear brown 

 colour. For use, add 5 parts of water to 1 of the stock 

 solution. 



Rosin wash is similar to the preceding, but contains an 

 oil, which gives it a more penetrating effect. 



Rosin wash is thus constituted : 



Powdered rosin 20 lb. 

 Caustic soda 3 \ lb., powdered fine. 



Fish oil 3 pints, which will be suffici- 



ent to make 100 gallons of wash. 



Mix these materials, and cover with about 2 inches of 

 water, and boil. When the liquid is clear, add water slowly, 

 still boiling the mixture, until the whole is made up to 15 

 gallons. This is the stock solution, sufficient to make 100 

 gallons of wash. In diluting this, only rain-water or soft 

 water should be used. 



Rosin and Whale-oil Soaji Compound. This is a still 

 more general insecticide. It consists of : 



Powdered washing soda 3 lb. 



Powdered rosin 4 lb. 



Whale-oil soap 10 11). 



To obtain it, boil the soda and rosin in 1 gallon of 

 water until they are dissolved, then make up slowly to 5 

 gallons, still boiling the mixture. In another vessel, dissolve 

 10 lb. of whale-oil soap in 5 gallons of water, by boiling. 

 The stock solution is made by mixing these two solutions. 

 This is sufficient to provide 45 gallons of wash. 



