DESTRUCTIVE INSECTS. 191 



is amenable to the same remedial measures as the plum cur- 

 culio. 



The Black Peach Aphis (Aphis prunicola} is a brownish-black 

 plant-louse (Fig. 257) infesting the leaves, twigs, and roots of 

 peach-trees. Trees less than three or four years old suffer 

 most from its ravages. Thousands of such trees have been 

 killed by it in Eastern peach-grow- 

 ing districts, and the pest has in- 

 vaded Northern orchards. 



Peach stocks should be care- 

 fully examined before setting, and 

 if there are any indications of 

 plant-lice on them, they should be 

 dipped in a strong kerosene emul- 

 sion or whale-oil soap solution. It 

 is a difficult matter to destroy the 

 lice on the roots after the tree is FlG - =57. -The Black Peach 



. __ , .. 1 j Aphis, wingless form, much 



set. Tobacco dust well worked in enlarged, 

 around the base of the trees has 



given relief in some cases. The lice which work on the tree 

 above ground can be killed with a spray of kerosene emul- 

 sion diluted ten or twelve times or with a kerosene-water 

 mixture containing 15 per cent, of kerosene. 



The Peach-tree Borer (Sanninoidea exitiosa} " has killed more 

 peach trees than all other causes combined," says J. H. Hale. 

 It is an American insect and has been a serious menace to 

 peach-growing for more than a hundred years. It sometimes 

 also attacks plums, prunes, cherries, apricots, and nectarines, 

 and has to be fought by nearly every peach-grower. 



The borer is a white, grub-like caterpillar (Fig. 258 c}, which 

 feeds on the inner bark, forming a tunnel or burrow, usually 

 on the trunk or large root below the surface of the soil. 

 Infested peach trees are easily distinguished by the large 

 mass of a gummy substance exuded from the wound and 

 mixed with particles of bark and excrement. The adult in- 

 sect is a beautiful, blue, wasp-like moth, the male (Fig. 258 b} 

 differing remarkably from the female (Fig. 258 a). 



In the latitude of New York the moths begin to appear in 

 the latter part of June and continue to emerge until Septem- 

 ber. A few hours after emerging the females lay their small, 



