BAN 6%, 
* 
a 3 . = A ees 
COURTESY OF DUKE UNIV. SCH. OF FOREST. 
FIGURE 85.—Galeries of the 
hickory bark beetle, Scoly- 
tus quadrispinosus, in 
phloem of hickory. Note 
short vertical egg galleries 
and fan-shaped larval gal- 
leries. 
spring. There is one generation per year in northern areas. In the 
south, there are normally two broods per year. 
The hickory bark beetle is not only the most important insect 
enemy of hickory, but also one of the most important insect pests 
of hardwoods in eastern United States (41). During drought 
periods, outbreaks often develop in the Southeast, and large tracts 
of timber are killed. At other times, damage may be confined to 
the killing of single trees or to portions of the tops of trees. The 
foliage of heavily infested trees turns red within a few weeks 
after attack, and the trees soon die. Control practices include the 
felling of infested trees and destroying the bark during the 
winter months or the storing of infested logs in ponds. To be 
effective, this type of control should be conducted over large, 
natural units. 
The shot-hole borer, Scolytus rugulosus (Ratz.), an introduced 
species, known to have been in the United States since 1878, now 
occurs throughout most of the Eastern States and in several 
Western States. It breeds in most of the common fruit trees and, 
to a lesser extent, in mountain-ash, wild cherry, wild plum, haw- 
thorn, and elm. The adult is grayish-black, and from 1.7 to 2.9 
mm. long. The elytra are covered with short hairs and are reddish- 
brown at the apex. The venter is shallowly excavated at the rear 
and unarmed. Because of its preference for broken, cut, or dying 
material, this species is of minor economic importance as a forest 
pest. There are one to three generations per year, depending on 
locality. 
Scolytus fagi Walsh breeds in beech and hackberry from Illi- 
nois to Texas. Adults are 4.5 to 5 mm. long. The elytral striae are 
238 
