is similar to those made by drywood termites, but there are no fecal pellets, and the frass is com-
pletely removed except for occasional deposits in unused galleries.
Carpenter ants also can nest in houses without attacking timbers. They simply use existing cavities,
including wall voids, hollow flush panel doors, termite galleries in wood, etc. Carpenter ants are
generally more of a nuisance when found crawling around the house foraging for food and water.
Ants are like termites because they live in colonies composed of several casts. There are winged
and unwinged queens, winged males, and several sizes of unwinged workers.
In addition to the presence of large black ants, other indications of an infestation are piles or scat-
tered bits of very fibrous and sawdust-like frass which the ants have removed from the wood. If the
pieces are from decayed wood, they tend to be darker and more square end. The frass will contain
fragments of ants and other insects mixed with the wood fibers. The frass is expelled from cracks
and crevices, or from slitlike openings called windows made by the ants. These "windows" are the
only external evidence of attack by carpenter ants. The frass is quite often found in basements, dark
closets, attics, under porches, and other out-of-the-way places. Faint rustling and even gnawing
sounds can be heard in the wood or cavity when the ants are active.
Good building practices that keep wood dry will contribute to a reduced risk of attack by carpenter
ants. These practices include: adequate clearance between wood and soil, good drainage and ventila-
tion, proper roof flashing, tight exterior wood joints, etc. If the wood cannot be kept dry, such as
that on some porches, decks, columns, etc., it should be pressure treated with an appropriate preserv-
ative. Chemical treatment of soil under and around a foundation to prevent subterranean termites
may not prevent attack by carpenter ants.
If carpenter ants are present, the nests should be treated with residual contact insecticide applied as a
dust or spray. The infested wood can be bored, the pesticide injected and the holes plugged. The
approaches and areas surrounding the nest should also be treated. Treating the areas where the ants
are seen is seldom effective, since many ants never leave the nest. For treating indoors, pesticides
specifically registered for that purpose must be selected. Poison baits may be available.
4.3.5 Powder Post and Other Wood Boring Beetles. The term "powder post" describes
a group of beetles that convert the inner portion of infested wood to a powdery or pelleted mass.
The thin outer shell on the surface of infested wood often shows numerous small holes through
which the beetles exited. These exit holes aid in the recognition and identification of beetle attack
(Table 4-3). Damage is probably heaviest in warm, humid climates but can occur throughout the
world. Table 4-3 summarizes the major characteristics of these important wood boring beetles as
well as other less serious pests which may be mistaken for them. A detailed discussion for each
group is provided below.