ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 



69 



Fig. 48. — Willow aphid: an infestation of the wingless form on a twig. 

 This dusky, relatively large aphid withdraws juices from leaves, causing 

 them to wilt and drop. 



Oystershell Scale, fig. 5. — See under Ash. Control Measure 

 3 or 5 (end of circular). 



YEW (TAXUS) 



Black Vine Weevil, Brachyrhinus sulcatus (F.), fig. 49. — 

 Rapid dying of yew — dying similar to that caused by transplant- 



