INSECTICIDE FORMULAE. 15 



CHAPTEE III. 



INSECTICIDE FORMULi«. 



Below we give the chief formulae for washes for winter, 

 spring and summer spraying, as recommended by leaxiing 

 experts. 



WINTER WASHES. 



These are to be used whilst growth is dormant only, 

 and for the purposes specified in connection with each. 



1. Caustic Alkali Wash — There are several ways 

 of preparing this solution, and the grower can choose the 

 one for which he can obtain the ingredients most easily. 



(a) Caustic soda (98 per cent, purity) lib. 



Caustic potash (80 per cent, purity) ... lib. 



Agricultural treacle fib. 



Water to make up to 10 gal. 



Dissolve the potash and soda separately in two wooden 

 buckets with a little water. Solution of these two chemi- 

 cals usually takes place with considerable violence and the 

 production of great heat, but if it is slow in starting the 

 addition of a very little hot w^ater will have the desired 

 effect. Mix the two solutions together, and stir in the 

 treacle, and make up to 10 gallons for use. If a stock 

 solution is to be kept to do a few odd trees at different 

 times, make up to only one gallon, and put in a bottle 

 fitted with an indiarubber cork. One part of this solution 

 will require nine parts of water to bring it to the correct 

 spraying strength. 



(b) Caustic soda (98 per cent.) lib. 



Carbonate of potash (80 per cent.) lib. 



Soft soap |lb. 



Water to make 10 gal. 



