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Kcriously attracting the attention of orchard ists in New 

 York may be discussed under the following heads: 



1. Plant Lice Injurious to Apple Foliage and Fruit. 



2. Insects that Factor in the Grading oi Apples. 



3. Insecticidal Properties of Various Sulphides. 



4. Compatibilities of Common Insecticides. 



5. Spraying as an Item of Expense in Apple Produc- 



tion. 



PLANT LICE INJURIOUS TO APPLE FOLIAGE 

 AND FRUIT 



Notwithstanding the admitted belief that the insects 

 are susceptible to various remedial measures, there is no 

 extensive body of evidence, wliich is positive and proven, 

 showing what can actually be accomplished in a practical 

 v-'ay towards the prevention of losses by the various species 

 {►i aphides that are injurious to bearing apple orchards. It 

 therefore seems worth while to direct attention to certain 

 experimental results which bear on the susceptibility of 

 these creatures to spraying mixtures. The matter is an im- 

 portant one because of the increasing shrinkage in apple 

 yields in consequence of the injurious activities of these 

 pests and the extreme difficulty of controlling the aphides 

 l»y the measures usually advocated, some of which are strik- 

 ingly at variance with experience and practice. 



In order that there may be clear understanding of the 

 present situation with respect to these pests, it is desirable 

 to briefly consider a few of the principles involved in the 

 eontrol of the apple aphides, the different species injurious 

 to apple foliage and fruit, life histories during early summer 

 on this host, and present status of spraying practices. 



The foliage and fruit of apples in New York are sub- 

 ject to attack principally l)y three species of plant lice:— 

 The rosy apple-aphis (Aphis sorbi Kalt.), the green apple- 

 aphis (Aphis pomi De Geer) and the oat-aphis (Aphis 

 avenae Fab.) It is safe to say that these insects have to be 



