Wood borer infestation

Bryan Blundell <jbb [at] prginc__com> writes

>There are several reasons why there are problems with adding boric
>acid instead of DOT (Disodium Octaborate Tetrahydrate). The best
>application would be an appropriate DOT/Glycol Mix formulation. The
>specific glycols that are used in a formulation are very important
>to the long term effectiveness of the application.

This is interesting and I will certainly try to do some experiments
with this product. I have not had the problems with staining you
mention or surface problems, but Robinson and Barlow (1993) did find
that DOT is persistent and present as a film.  I like Boric acid
powder as it is easy to remove from the surface.  The penetration
appears to be limited even with DOT as a solution, Robinson and
Barlow state"

   "Two applications of 10% DOT to wood with 16-18% WMC, followed by
    6 wk in a 85% RH environment resulted in greater amounts of
    boron detected at the 3000 um depth than did other treatments.
    The results of the evaluations reported here indicate that the
    amount of boron detected on and below the wood surface, to the
    depth of approximately 2 mm, should provide protection from
    woodinfesting beetles."

        --From
        William H. Robinson and Robert A. Barlow.
        "Diffusion of Disodium Octaborate Tetrahydrate Into Southern
        Yellow Pine to Control Wood-Infesting Beetles"
        Urban Pest Control Research Center, Department of
        Entomology, Virginia Polytechnic Institute and State
        University,Blacksburg, VA 24061-0319, USA, in Proceedings of
        the First International Conference on Urban Pests. K.B.
        Wildey and Wm H.Robinson (editors). 1993
        Available online at

            <URL:http://www.icup.org.uk/reports%5CICUP626.pdf>

Boric acid can be obtained from chemical supply houses or medical
sources without the usual blue colorant found in applications for
insects in hardware stores, DOT, however comes as,

   "A liquid insecticide solution comprising a 5% to 20% water
    solution of a disodium octaborate tetrahydrate ("DOT") mixture
    comprising disodium octaborate tetrahydrate, colored pigment,
    and a bittering agent of either sucrose octa-acetate and
    denatonium benzoate, is provided. Preferably, the insecticide
    solution is prepared by stirring a powdered DOT mixture into
    water. Methods for treating wood surfaces and preparing bait
    stations with liquid insecticide solutions prepared with D.O.T.
    mixtures are also provided."

        --From
        US Patent Office:
        Insecticide including disodium octaborate tetrahydrate and
        method for treating wood therewith
        United States Patent 6399109

        <URL:http://www.docstoc.com/docs/
            51374836/Insecticide-Including-Disodium-Octaborate-
            Tetrahydrate-And-Method-For-Treating-Wood-Therewith
            ---Patent-6399109>

DOT is most available as TIMBOR (see
<URL:http://www.allpestexpress.com/timbor.aspx> ), but is sold in
other formulations by independent companies who mix it with
different agents for various effects, (see the Material Data Sheet
for an example at

    <URL:http://www.controlsolutionsinc.com/
        data/products/other/37_Borrada%20LP%20MSDS.pdf>,

a mixture with various additives which can produce other reactions
and staining.  It seems that one should be careful to apply either
in any situation and one must tailor work to meet specific
requirements.

    **** Moderator's comments: The above URLs have been wrapped for
    email. There should be no newlines.

Niccolo Caldararo
Director and Chief Conservator
Conservation Art Service


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                  Conservation DistList Instance 24:34
                Distributed: Thursday, January 13, 2011
                       Message Id: cdl-24-34-005
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