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NEBRASKA STATE HORTICULTURAL SOCIETY. 



one to several inches below the surface, where it does much injury. 

 It is especially destructive to nursery stock where it is permitted to 

 multiply from year to year. The presence of this root form is read- 

 ily detected by the wart-like swellings which its attacks produce upon 

 the roots ; also by the " moldy " appearance of the root and surround- 

 ing earth. The lice insert their beaks into the bark of the roots and 

 extract the juices which would otherwise go to nourish the tree. 

 When they are very numerous their injuries cause the roots to grad- 

 ually decay ; and if they continue in their attacks the trees eventually 

 die. 



Fig. 1. — The Apple-tree Root Louse : a, rootlet showing 

 galls ; b, wingless or apterous louse ; c, winged insect ; d, 

 e, f, and g, parts of louse, showing structure. Figs, all 

 magnified, except a. [After Riley.] 



If upon examination you should discover these irregularities upon 

 the finer roots of your apple trees, and at the same time notice the 

 moldy looking spots, you may be sure that this louse is present, 

 and needs looking after. A closer examination will reveal the small, 

 pale-yellow lice, which sit concealed beneath their flaky covering 

 in the crevices of the root deformities which their attacks have pro- 

 duced. These are also frequently accompanied by winged individ- 

 uals of larger size. The wingless lice have their bodies covered with 

 a bluish-white cottony substance, already mentioned as the " moldy " 

 substance, which is secreted from the upper portion of the bodies of 

 the wingless lice and hang's to their bodies in a tuft of filaments which 

 are frequently five or six times the length of the lice themselves. In 

 Fig. 1, a represents the affected root, b a wingless louse, and c one 

 with wings. The size of these insects is indicated by hair lines along- 

 side of the figures. 



