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Insects of Shade Trees and Their Control. 5 
LINDEN BORER.” 
How injurious —This insect apparently attacks only linden, but 
on this it is common and occasionally quite injurious. It is more or 
less generally distributed over the eastern United States. 
How recognized.—Toward the end of summer tips are found killed 
and the green bark of growing shoots, leaf stems, and larger veins 
on the underside of leaves are eaten. This is the work of the 
beetles and is quite noticeable when the insect is abundant. Bur- 
rows made by a slender grub occur under the bark and deep in the 
wood (fig. 35, 77, 76) of the trunk nearer the ground, in exposed roots, 
and in lower limbs. 
Habits of the insect—The beetles (fig. 35, 75), which are long- 
horned with six black spots on the middle of the back, issuing out 
of holes (fig. 35, 72) im the bark, begin to appear in May, and after 
Fig. 35.—Linden borer and work: 11, Burrows in cross section; 72, circular exit hole 
of the beetle; 13, wound made by borer; 14, frass thrown out by larva; 15, beetle; 
16, grub in the gallery under the bark which was cut away. (TF elt.) 
feeding awhile the females make with their jaws slight incisions in 
the bark and lay two or three eggs in each. One female lays about 
90 eggs. The grubs (fig. 35, 76) that hatch from these make the bur- 
rows mentioned above and, after an undetermined length of time, 
change to pup and then to beetles which leave the tree through 
holes in the bark throughout the summer. 
Remedies.—On valuable trees the injury may be checked by dig- 
ging out the borers. Probing with wire, injections of carbon disul- 
phid (p. 14), and spraying with poisoned miscible-oil solution (p. 
13) in the late summer are other serviceable means of killing this 
borer. Heavily infested and badly damaged trees are best cut and 
burned during the winter. 
89 Saperda vestita Say. 
