ee 
produce heavy populations and trigger off outbreaks (699). Some 
degree of control is possible by cutting infested trees in the fall 
and removing them from the woods before spring, or by storing 
the logs in water. 
The eastern larch beetle, Dendroctonus simplex LeC., occurs in 
the Northeastern States south to West Virginia and west to 
Minnesota. It also occurs from coast to coast in Canada and north- 
westward to Alaska. Its preferred host is eastern larch, Larix 
laricina, but it has also been recorded from red spruce. Adults are 
dark brown, the elytra often having a reddish cast, and are from 
3.4 to 5 mm. long. | 
Winter is spent mostly as young adults in the brood gallery; 
otherwise as larvae. Adults are active from May until late Au- 
gust. Eggs are deposited in niches arranged in alternate groups | 
of three to six eggs each along the sides of longitudinal, more or 
less winding galleries. The larval mines are in the inner bark and 
are quite short. Adults responsible for this brood may re-emerge 
and construct several additional galleries during the season. Up 
to three broods may be produced. The first of these reaches ma- 
turity by mid-summer and the second, by mid-September. The 
third brood spends the winter as larvae or young adults. | 
The eastern larch beetle is not generally considered to be im- | 
portant economically, because of its preference for dying or in- 
jured trees. Living trees may be attacked and killed at times, 
however, but are usually only after being weakened by other 
causes, such as larch sawfly defoliation. 
The genus Phloeosinus Chapuis is represented in North Amer- 
ica by at least 40 species, five of which occur in eastern forests 
(77). They breed preferably in cut, broken, or decadent conifers; 
in short, longitudinal egg galleries constructed between the bark 
and wood. Newly-emerged adults feed briefly before attacking a 
new host. Sometimes they clip off and eat young leaflets on 
healthy trees. Generally, however, they bore into the twigs, goug- 
ing out much sapwood. This occasionally causes the twigs to wilt, 
die, break, and drop to the ground. 
Phloeosinus dentatus (Say), the eastern juniper bark beetle, 
occurs from New Hampshire to Georgia and westward to Texas 
and Nebraska. Its most common host is eastern red cedar, but it 
also attacks arborvitae and Atlantic white-cedar. The adult is 
piceous-brown to black, is clothed with rather abundant short, 
gray hairs, and is 2.25 to 2.8 mm. long. Eggs are laid in short 
galleries that extend upward from the entrance hole. The larvae 
mine for short distances across the grain, then upward with the 
grain (fig. 91). Infestations are usually found in cut, broken, 
or fire-damaged trees. Attacks have been reported on living over- 
topped red cedars infested with the root rot fungus, F'omes an- 
nosus, in North Carolina. Neither the insect nor the fungus 
working alone usually killed the trees. Working together, how- 
ever, they killed trees of all sizes (41). Cutting and burning of 
infested twigs and keeping the trees in a healthy condition should 
be helpful in control. 
Phloeosinus taxodi Blackman, the southern cypress beetle, 
breeds in bald cypress and probably occurs wherever its host 
grows in the South. The adult is brownish-black to black, has 
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