Female beetles lay eggs in cracks or crevices on the wood surface or bore short 
tunnels in bark-free wood. 
None of the more than 60 native species attacks bark-free wood except possibly 
the leadcable borer, Scobicia declivis (LeConte), in the West (367). Seasoned 
wood suffers no damage of major economic importance caused by any species 
native to eastern North America. Attacks are initiated in partially seasoned wood 
containing bark. Females bore short tunnels into the outer sapwood and deposit 
eggs. Once attacks are initiated, larvae of many species may continue to feed and 
develop at a reduced rate. Adults may emerge from wood in use, usually within a 
year, but possibly even as long as 5 years after tree felling. Because bostrichids 
differ from lyctids in adult appearance, size of exit holes, and frass, bostrichids are 
referred to as false powderpost beetles. Many other species attacking trees are often 
called branch or twig girdlers, a name more appropriate to their habits. 
Adults of native species are reddish brown to black and 3 to 6 mm long. They 
resemble adults of the family Scolytidae but differ in that the pronotum is tubercu- 
late and rasplike, the tarsi are five-segmented, and the antennae are straight rather 
than elbowed. The antennal club is three- or four-segmented; the thorax is usually 
hoodlike, covering the head; and the posterior portion of the elytra is frequently 
concave and tuberculate. The femora and tibiae are broad and the latter are 
frequently toothed on one margin (425). 
Xylobiops basilaris (Say), the redshouldered shothole borer, is a common 
species, widely distributed over much of the Eastern United States. The adults are 
basically black but the basal part of the elytra is dull reddish-orange, hence the 
common name (fig. 110). Hickory, pecan, and persimmon are most frequently 
infested, but several other hardwoods are also attacked. Larvae feed parallel with 
the grain, mostly within the sapwood, but heartwood may be damaged to some 
extent. Populations may be high, thus extensive damage may result. Feeding may 
continue until the wood is very dry. Adults often emerge from wood within 
structures such as firewood. 
The apple twig borer, Amphicerus bicaudatus (Say), is another common species 
in most of the Eastern United States. It breeds in dying wood such as large 
prunings, exposed roois, and injured branches of most shade and fruit trees. Some 
of the many other species and the woods they attack are: Lichenophanes arminger 
(LeConte)—various hardwoods, chiefly oak; L. bicornis (Weber)—sycamore, 
hackberry, oak, pecan, hickory, apple, beech, elm, black locust; Scobicia bidentata 
(Horn)—hickory, elm, oak, chestnut, hackberry, and sassafras. 
Several native bostrichids commonly attack softwood timbers. Adults may 
emerge within structures from bark-covered wood that is used as structural timbers 
or rustic furniture. Stephanopachys rugosus (Oliver) is widely distributed in the 
Eastern United States. It and several other species in the same genus—S. densus 
(LeConte), S. cribratus (LeConte), and S. hispidulus (Casey)—breed in pine. S. 
substriatus (Paykull), found in most of the Northern States, attacks Douglas-fir and 
hemlock, as well as all species of pines and true firs. 
Many of the tropical species are frequently intercepted during quarantine inspec- 
tions at ports of entry to this country. Even though tropical in origin, at least two 
species are established in some Southern States. 
The bamboo powderpost beetle, Dinoderus minutus (F.), occurs in Florida and 
Louisiana. It is frequently intercepted in bamboo products at ports of entry. Adults 
are reddish brown to brownish black and are 2.5 to 3.5 mm long. The wing covers 
Zo 
