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Jersey to Virginia are wholly exempt from it. In connection with 

 this fact lies the explanation of another one now generally accepted 

 by Maryland and Delaware growers, viz. : that young trees do not 

 thrive ivhen set in old orchards, or in their immediate vicinity. This 

 statement appears to be true; and yet it is in marked contrast to the 

 experience in Michigan, where, for more than ten years, thousands 

 of young trees have been set successfully in place of old trees which 

 were removed on account of yellows or for other reasons. I can 

 only explain this contradiction by supposing the insect to be rare in 

 Michigan. Along the Atlantic coast this aphis deserts the roots of 

 old trees for the more succulent tissues of young ones whenever 

 there is an opportunity. If it were abundant in Michigan the re- 

 sults of replanting would probably be much less satisfactory and 

 more in harmony with the experience of eastern peach growers. 



Save in exceptional years, when young orchards have suftered 

 seriously, and when whole nurseries have been destroyed, the injury 

 to the parts above ground Is inconsiderable. The Spring of 1890 

 was one of these exceptional periods. The aphis appeared before, 

 or soon after the buds germinated, and was so abundant that hun- 

 dreds of shoot-axes dried up and died before they were one-half an 

 inch long. After a few weeks all of the older trees got the start of 

 the aphides, but even on these I saw limbs one-fourth of an inch in 

 diameter which died, because all of their growing buds had been 

 destroyed. 



Frequently, for years together, this aphis is not common enough 

 above ground to attract any attention. Then, for a season or two, 

 it will be very abundant. 



Although I have not seen it in New Jersey, that is only because 

 I have not traveled there extensively. It is well known to Jersey 

 peach growers, and especially to nurserymen living in the middle 

 and south part of that State, where, in time past, it has done great 

 injury, and where it appeared this year in very considerable numbers. 



Undoubtedly this aphis is often transported with nursery stock. 

 Being on the roots when the trees are dug and packed, there is no- 

 thing to prevent its transportation. Indeed, unwittingly, I introduced 

 it myself into one locality in Michigan along with nursery trees from 

 Maryland, not, however, into a peach region. The next season it 

 appeared on the branches and roots, but only upon the introduced 

 trees. The same season, many miles distant, at South Haven and 

 St. Joseph, in the southwestern part of the State, I saw peach-trees 

 with the peculiar stunted appearance which I have so frequently seen 

 in the East. I pointed out this similarity to various gentlemen, and. 



