Wood borer infestation

Niccolo Caldararo <caldararo [at] aol__com> writes

>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
>>...
>>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.

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.

    Boric Acid is not labeled for wood treatments

    Boric Acid is soluble to about 4% in water were as DOT is
    soluble to 15%. 4% is not a level high enough to be effective.

    Boric Acid is corrosive to metals were DOT has corrosion
    resistance.

    Boric Acid in the presents of iron within the wood will cause
    staining in the wood. The DOT will not.

    The Boric Acid application will most likely leave a crystal
    residue on the surface where the appropriate DOT/Glycol Mix
    formulation (BoraCare) will not.

Hope this is helpful,

Bryan Blundell
Technical Support
PRG, Inc.


                                  ***
                  Conservation DistList Instance 24:33
                Distributed: Wednesday, January 5, 2011
                       Message Id: cdl-24-33-001
                                  ***