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 4.3.5.1 Classifications.
Anobiids, sometimes referred to as death watch beetles or furniture beetles, are
found on recently seasoned and older hardwoods or softwoods throughout the United States. Sap-
wood, particularly that close to the bark, is preferred because it contains the highest percent of star-
ches, sugars and protein. Unheated buildings or houses built with crawl spaces over damp ground,
as often occurs in the southeastern United States, are particularly susceptible, but houses are usually
ten or more years old before damage becomes obvious.
It is very difficult to detect an anobiid infestation. During and after emergence, a bright and light-
colored powdery frass and tiny pellets will be found streaming from the exit holes or accumulating
underneath infested wood. The frass in the galleries is loosely packed and does not tend to fall free-
ly from the wood unless the wood has dried out considerably since the attack occurred. The exit
holes are round and vary in diameter from 1/16 to 1/8 inch (Figure 4-21). The anobiid pellets are
smaller than those excreted by drywood termites and taper towards each end. Some pellets are bun
shaped. When anobiid infestations die out naturally, the frass is yellowed and partially caked on the
surface.
In most old, heavy infestations there are very tiny round exit holes, about 1/32 inch (0.6 mm) in
diameter, scattered over the infested surface. These are emergence holes of parasitic wasps, the lar-
vae of which feed on the beetle larvae.
Lyctids beetles attack the sapwood of hardwoods. They probably cause more
damage to U.S. hardwoods than any other group of beetles and are also an important pest of im-
ported hardwood products. Ring porous hardwoods such as oak, hickory, and ash are the most sus-
ceptible, but semi-ring and diffuse porous woods such as walnut, pecan, poplar, sweetgum and wild
cherry are also susceptible. The greatest activity of the beetles occur where the wood moisture con-
tent is between 10 and 20 percent, but beetle activity can occur where the moisture content ranges
from 8 to 32 percent.
The female deposits eggs in the pores of the wood (pores must be at least 1/325 or .003 inches in
diameter) or possibly in cracks and crevices. When the larvae hatch, they first bore along the ves-
sel, thus enlarging the tunnel as they grow. The tunnels are straight and initially along the grain, but
later become more irregular and often intersect other tunnels. Mature grublike larvae are usually
less than 1/4 inch, curved, wrinkled, enlarged at the thorax and have six legs. The larvae form a
pupal chamber just under the wood surface. The adult beetle then cuts its way to the surface form-
ing a circular exit hole. The entire life cycle usually requires 9 to 12 months, but may be shorter if
conditions are favorable. One species can complete a life cycle in 4 months. The beetles will rein-
fest the same wood source.
Infested wood does not show any external evidence of attack until the first generation of adult
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