8o BEGINNERS^ GUIDE TO FRUIT GROWING 



age with paris green, arsenate ■ of lead or other 

 poisons. The sucking insects, however, cannot be 

 poisoned by any means, and it is, therefore, neces- 

 sary to spray them with some caustic or irritating 

 substance which kills when it touches them. 



PARIS GREEN 



Among the poisonous sprays paris green is the 

 best known. It is applied after mixing i pound of 

 paris green in loo to 200 gallons of water. A pound 

 of lime ought to be added to this mixture, however, 

 to neutralize free arsenic, which would otherwise 

 burn the foliage. The paris green can be added 

 directly to the bordeaux mixture. This is a favor- 

 ite way of using it. 



ARSENATE OF LEAD 



Probably the most popular and satisfactory poi- 

 son used against chewing insects at present is 

 arsenate of lead. This comes in various forms fnom 

 the dealers — usually, however, as a paste. It is 

 mixed at the rate of 3 pounds to a barrel of water. 

 This has the same uses exactly as paris green, but 

 is safer, as it does not injure the foliage. Further- 

 more, it has the good quality of holding on to the 

 foliage. Arsenate of lead may be mixed with bor- 

 deaux mixture, and in fact this is the customary 

 way of applying it. 



LIME-SULPHUR WASH 



This spray solution is used chiefly for killing the 

 San Jose scale, and has been found on the whole the 



