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Subject: Insect infested tortoiseshell tabernacle

Insect infested tortoiseshell tabernacle

From: Terry Conners <tconners>
Date: Monday, November 6, 2006
Jason Clancy <g00067963 [at] gmit__ie> writes

>If anyone has treated tortoiseshell objects with insect infestations,
>I would like to get your opinions on how to treat the problem.

Presumably you are looking for an alternative to fumigation with
methyl bromide etc.? I recently went through something similar, and
the university entomology specialist recommended thermal treatment.
It may be appropriate in this case as well, depending on how the
tortoiseshell is attached and on whether the thermal shrinkage
characteristics of tortoiseshell are similar to the wood substrate.
The procedure is as follows:

    1.  Wrap the infested item in a cloth bed sheet

    2.  Place the sheet-covered items in a large polyethylene bag
        (e.g., large trash bag) or simply wrap them in polyethylene
        and tape the seams. Force as much air out of the bag as

    3.  Place bagged items in freezer at -20 deg. C (-4 deg. F) for
        seven days.

    4.  After seven days, carefully remove the items from the

    5.  Before removing items from the polyethylene bag, allow to
        gradually warm up to room temperature. This may take 24
        hours for larger items. This step insures that any
        condensation forming will occur on the outside of the
        polyethylene bag rather than on the item itself

Take extra care when handling crafts and fragile items immediately
after freezing and before they have returned to room temperature.

The above chilling procedure generally is effective in killing all
pest life stages, including eggs. Adverse effects seldom occur to
furniture or their veneers and finishes. Wood inlays or
mother-of-pearl, however, may be affected. Infested rugs, woolens,
fabrics, pet food, animal trophies, etc. can also be treated in this
manner, again with negligible adverse effects.

Heat would also be effective, but you would have to raise the heat
to 55-65 deg. C (150-170 deg. F) for one to several hours (for
larger pieces), depending on the size of the piece. Do this in an
oven with a pan of water, misters, etc. to keep the relative
humidity high during this process, otherwise the wood will dry out
and shrink and, this may cause other unanticipated problems.
Freezing the wood will not cause this sort of difficulty, and the
shrinkage of wood due to thermal effects alone is essentially

Terry Conners, Ph.D.
Forest Products Specialist
Department of Forestry
University of Kentucky
202 T.P. Cooper Building
Lexington, KY 40546-0073

                  Conservation DistList Instance 20:26
                 Distributed: Monday, November 13, 2006
                       Message Id: cdl-20-26-008
Received on Monday, 6 November, 2006

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