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YARD AND GARDEN 



leaves, fruit or flower. If the insect, however, 

 is of the sucking variety, injuring plants by the 

 gradual consumption of plant juices — such as 

 the thrips, plant-lice, scale insects and mites — 

 then a poison must be used that will act exter- 

 nally upon the bodies of the insects. Obtaining 

 their food by inserting their sucking beaks into 



Typical Chewing Instct (Cecropia motli) 



the soft tissues of the plant that lie below the 

 external covering, they escape poisons that 

 would prove fatal to the chewing insect and 

 must be combated, therefore, by other and more 

 direct means, such as the employment of caus- 

 tic substances, those that will smother them by 

 closing or clogging their breathing pores, or 



