438 GENERAL SCIENCE 



II 



Fungicides. Most of the harmful fungi may be killed 

 by the use of Bordeaux mixture. It is made with differ- 

 ent amounts of copper sulphate and lime according to its 

 intended use. 



BORDEAUX MIXTURE 



Copper sulphate . . . . 2, 3, 4, 5, 6, pounds 



Lime equal to copper sulphate 



Water 50 gallons 



There should always be enough lime to give an alkaline 

 reaction on litmus paper ; otherwise the leaves may be 

 scorched. It should be remembered that Bordeaux mix- 

 ture is especially effective on fungi and has very little 

 effect on plant insects. 



