Some Insects of the Apple and Their Control, 1735 



Treatment. — The trees, especially in young plantings, should 

 be inspected every fall and spring for discolored areas in the bark, 

 or for wounds from which there is exudation of sap, or for saw- 

 dust-like castings. When such are detected cut out the borers by 

 means of a strong, sharp knife. Grubs buried deeply in the 

 heart-wood may sometimes bo destroyed by probing with a piece 

 of wire or by injecting carbon bisulphide into the burrows, when 

 the openings, after the application, should be immediately sealed 

 with moistened clay or putty. As unthrifty trees are more sus- 

 ceptible to attack, the needs of the orchard in other respects should 

 be given careful attention for the purpose of stimulating the 

 trees to outgrow the injuries and of warding oif subsequent 

 attacks. 



Insects Incrtjsting the Bark of Apple Trees 



some common scale insects 



The scales constitute a peculiar group of insects which differ in 

 many ways from the active and highly-colored forms usually 

 familiar to the casual observer. They are generally very incon- 

 spicuous because of their small size, dull colors and sedentary 

 habits. When abundant they appear as a scurfy deposit upon 

 the bark, which is dark grey, whitish or brown in color, depending 

 upon the species. If the insects are numerous the bark appears 

 rough, scaly and unhealthy because of the obscuring of its natural 

 color and polish. If one of the filmy bodies of the San Jose scale 

 is raised carefully with the point of a pin or of a knife blade a 

 small grub will be discovered beneath. This grub is the insect 

 itself and the filmy or scurfy body above is its protective covering 

 or scale, which, strange to say, is composed of the cast skins and 

 a waxy substance from the insect's body. Hence the name " scale 

 insect." 



the SAN JOSE SCALE 



This species ranks as one of the worst pests of fruit trees. 

 Besides the apple, it attacks the cherry, pear, peach, plum, cur- 

 rant — j:)ractically all our common orchard trees and bush fruits. 

 It thrives also on many shade trees and ornamental shrubs. 



Large numbers of this scale appear as a greyish, scurfy deposit, 

 not unlike a coat of ashes. The bark appears rough and dull 



