Insect and Disease Control 233 



With the renewal of tree growth in the spring, the larvae 

 again become active and, as above indicated, bore into the 

 ends of the young shoots and burrow into the pith for a 

 distance of -J- inch to \\ inches, causing the death of the 

 terminal end of the shoot. 



The larvae of the generations occurring during the summer 

 attack the fruit, and it is to this habit of the insect that its 

 most serious damage is due. It may bore into the pit if 

 it is still soft when it enters, or it works in the flesh about 

 the pit later in the season. It is the minute, partially de- 

 veloped larvae of the last brood that pass the winter in the 

 crotches of the tree as above described. 



Methods of control. 



As a rule orchards that are thoroughly treated according 

 to the usual spraying program for San Jose scale and cur- 

 culio require no special treatment for this insect. While 

 some have doubted the value of lime-sulfur mixtures, others 

 have found them successful when applied very thoroughly 

 just as the buds are swelling and starting into growth in 

 the spring. The arsenate sprays for curculio also doubtless 

 destroy many of the small larvae. 



Black peach-aphis {Aphis persicce-niger) 



The black peach-aphis is a small, soft-bodied insect 

 closely related to other aphides or "plant-lice" that occur 

 on apples and a great variety of other fruits and plants. 



Appearance. 



The insect is about -^^ "^^h long and is shiny jet black 

 or very dark brown in color. Both winged and wingless 

 forms occur. 



