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.

Is it actually active, the infestation? Does the log have bark on?
Is the infestation in the sapwood?

It is difficult to advise what to do unless you give information
about why you want to preserve the log, and what you are intending
to do with it. What size is the log? When you say the wood will be
moved for seasoning implies that the wood will be processed into
some new form.  Will it be boards? If so have it milled into boards
and then kiln dried.  That will kill off any wood borers.  Is it
going to be a totem pole, or a ship's mast?

If it is meant to stay as a whole log your only options will be
either heat treatment or freezing.

I think it is 52 deg. C that kills off all stages of all
insects--Thermo Lignum have a heat treatment method where RH is
strictly controlled during heating up and cooling down. For freezer
treatment, a temperature of minus 30 deg. C will have to be achieved
throughout the entire log for a period of days to ensure 100 per
cent kill.

Where are you? My museum service has a large walk-in freezer that
can get down to minus 35 and it can be hired. We are in Leeds,
England.

The practicalities of treating a whole log are going to be
quite difficult, and expensive, and unless there is a compelling
reason to use that particular log I would be looking to source one
from a reputable supplier.

Wood borers eat dead, damp wood, they are part of the process of
decay.  Has the log in question been in damp conditions, like a
forest floor?

Ian Fraser
Conservator
Leeds Museums and Galleries
Temple Newsam House
Leeds LS15 0AE


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                  Conservation DistList Instance 24:30
                 Distributed: Sunday, December 19, 2010
                       Message Id: cdl-24-30-003
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