of its range, an additional 2 to 3 years may be necessary. The 
length of the cycle may also vary considerably in a given building. 
In attics, where generally warmer temperatures prevail, adults 
may emerge up to 2 years earlier than those in wood in the 
basement. 
The old-house borer causes severe damage in houses and other 
buildings. Structural timbers (fig. 73 B), framing members, and 
other wood parts are seriously weakened by its mining and tun- 
neling. Air-dried pine floor joists, plates or sills, and sub-flooring 
are apt to be damaged most severely. Other framing such as 
studs, stair carriages, furring strips, and roof rafters are some- 
times attacked. 
When an old-house borer infestation is discovered, two types of 
remedial action are necessary: (1) the repair or correction of 
serious structural defects and (2) controlling the remaining in- 
sects present in wood left in place (486). 
Chlorophorus annularis (F.), has been recovered from infested 
imported bamboo at several locations in this country, and it may 
be established here. The adult is blackish, with green markings 
on the thorax and a yellow, X-shaped mark on the elytra, and are 
about 10 mm. long. The first two pairs of legs and the inner parts 
of the antennae are red. Well-seasoned bamboo is mined exten- 
sively, and the mines are tightly packed with fine, powdery frass. 
This species is a serious pest of bamboo in India and Japan. 
F, 494430, 494432 
FIGURE 73.—The old house 
borer, Hylotrupes bajulus: 
A, adults; B, damage. 
207 
