Jennifer Williams inquires concerning problems a library is having with
ants, thought to be carpenter ants. She describes a variety of
approaches the institution has taken already, "Set ants traps, put down
a commercial ant bait around the building, washed down
walls with ammonia water."

The reason they have seen no improvement is two-fold. First, and most
fundamentally, they haven't addressed the reason they have the carpenter
ants to begin with. Likely there is a parent or main colony (with queen
and brood) somewhere, perhaps with one or more satellite colonies (never
with eggs or small larvae, only workers, mature larvae, and pupae) in
the library, probably where there is a water problem. So, the first step
would be to begin taking a long, hard look at current conditions --
leaking roofs (they can live in roof insulation, for example), stopped
gutters or scuppers, clogged drains, leaking plumbing, poor drainage,
etc.  If none are found (they usually are, but in a few instances the
colonies aren't associated with moisture) then you must begin to search
out dry, warm, undisturbed areas. When these problems are found, they
must be repaired. During this process damaged wood or insulation should
be removed, manually removing as much of the satellite colony as
possible. The remainder can be treated with Drione or some similar
product.

Second, they must search out the parent colony and destroy it. It may be
located in a diseased tree, or a stump, or a pile of wood. So, how do
you go about this? Carpenter ants are nocturnal, so the best time to
find them foraging out from the main colony is around midnight.
Carpenter ants will move all debris out of the trails, so if you are
careful, and do your searching at night, it is usually fairly easy to
find the main colony. Once found, this main colony must be destroyed.
Again, a dust is usually a good choice and often requires less active
ingredient than with a liquid.

Typical commercial treatments cost around $150 to $300 (at least in this
area), but aren't usually too successful, since they don't address the
issues I've raised -- identify and remove satellite colonies, eliminate
moisture problems, get vegetation away from the building, eliminate
decorative bark mulch (a favorite of carpenter ants), etc. Can the
institution do this work themselves. Well sure, if they have the
stamina. Otherwise, they are going to need a good PCO with experience
dealing with carpenter ants.

Hope this helps, but feel free to contact me directly if you have
questions.

Best,

Michael Trinkley, Ph.D.
Director
Chicora Foundation, Inc.
PO Box 8664
Columbia, SC  29202
803/787-6910
Email: [log in to unmask]
www.chicora.org