Wood borer infestation

Jennifer Brian <jenniferfbrian [at] gmail__com> writes

>I have come across a large pine log (approximately 1m diameter, 2.5m
>long) with borer infestation. The log is too large for any freezer
>that I have access to and we do not want to use pesticides as it is
>to subsequently be used. I was wondering whether anyone has
>undertaken anoxic, or black bag, treatment of any large wooden
>objects, and how effective they were on objects with a small surface
>area to volume ratio.  If they are ineffective, do you have any
>suggestions for other appropriate treatments?  The treatment will be
>undertaken in-situ before the log is moved for seasoning.

This is an interesting question, one that I have been asking pest
experts for some time about as the pressure for treatment that
produces 100% kills of adults and eggs without pesticides has
increased in recent years.

A pest control provider a few years ago answered my question about
the "black bag" treatment suggested here in Marin for containing Oak
disease.  He suggested that the claim that placing a wooden object
in a black plastic bag in the sun to kill insects was interesting
but he could not find any reference of its utility even though UC
Berkeley's Wood Products Lab had suggested it to the media. He
proposed trying a test but adding boric acid to the bag.  He argued
that convection currents created by the heat of the sun in the bag's
moisture and the wood could carry the boric acid into the wood over
a period of several weeks exposure and might be effective.

I tried this, cutting open a limb in my yard to see if there were
active insects and, this verified, tried the treatment.  After 6
weeks I cut into the limb in two places and could not find live
insects. This does not mean that there were none, of course, as two
cuts would not be a statistical test, nor could I take the time to
test the viability of eggs I found. Someone with the time and money
should look into this.

Niccolo Caldararo, Ph.D.
Conservation Art Service
San Francisco, Ca.


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                  Conservation DistList Instance 24:31
                 Distributed: Monday, December 20, 2010
                       Message Id: cdl-24-31-003
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