286 



SPRAYING MIXTURES 



dilution will depend entirely upon the strength of the con- 

 centrated solution and the kind of trees to be sprayed. 



SPRAYS FOR CHEWING INSECTS 



Arsenate of Lead. Arsenate of lead is used exten- 

 sively to-day for chewing insects. It sticks better than 



Fig. 154. Spraying with arsenate of lead, just after petals fall, for codling moth worm. 



Paris green and is not so likely to burn the foliage. When 

 the lime and sulphur sprays are used as a fungicide, it is 

 one of the few poisons that can safely be mixed with them. 

 Formula: 



Arsenate of lead 2 Ib. 



Water 50 gal. 



This poison is usually sold in small kegs and comes in the 

 form of a paste resembling white lead. Some companies 

 manufacture it in the powdered form. In such cases 

 but half the amount (by weight) recommended in the 

 formula should be used. 1 



Paris Green. Paris green may be safely used with 

 Bordeaux mixture, but not with the lime-sulphur sprays. 



1 Arsenate of calcium has given good results as a substitute for arsenate of 

 lead and may be used on all except the stone fruits. 



