OAK PRUNER 281 



the power of causing the galls to jump an inch or more, as a result 

 of the activity of the insect (Neuroterus saltatorius Edw.) within. 

 The galls are somewhat depressed and found embedded in the leaf 

 in such a way as to cause a slight convexity on the upper surface. 

 They are yellowish when they are detaching, and about one-half 

 inch in diameter. 



Oak Pruner (Elaphidion villosum Fab.). This beetle is rather 

 slender and grayish brown in color; its mouth-parts are rather 

 weak. The larva or grub is obliged to cut its way out of the bur- 

 row before pupation. The female deposits her eggs in midsummer 



FIG. 285. The oak primer, beetle, larva, and larva in burrow. 



on the smaller twigs. The grub eats the limb nearly off and then 

 waits for the wind to break it off (Fig. 285). The twig, lying on 

 the ground, is kept moist during the winter a condition favorable 

 for the development of the larva and pupa. The adult beetle 

 emerges from the twig in the spring. This is the usual procedure, 

 but the life cycle may be completed on the tree. 



Injury. This natural pruning of the oak is not particularly 

 injurious. The insect attacks maple as well as oak, and has been 

 recorded on apple, plum, pear, peach, grape, hickory, locust, 

 sumac, and other trees and shrubs. 



