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 wood, but not in rotten wood.
Biological Tests. It is important to detect and treat decay fungi as early
as possible if the strength properties of the wood are to be maintained.
Biological tests are still the most reliable means for detecting early stages
of decay.
Culturing. The early or "invisible" stages of decay can be detected by cul-
turing in the laboratory the core samples you have collected in the field
using increment borers. Each core is placed in a plastic straw, labeled
and the ends of the straw stapled shut.
The cores are brought to the laboratory and culturing begins within 24
hours.
Insect Identification. It is usually beneficial to identify insects if an infes-
tation has occurred. If field identification is not possible collect the in-
sect, their boring dust (frass), and a portion of the wood with typical
damage, and consult the cognizant Pest Management Consultant (See
Appendix A) for assistance with identification.
Determination of Serviceability. The results of your visual and physical
inspections and lab reports help you determine the serviceability of the
wood member. As the integrity of a wood member is destroyed by
biological agents, its ability to withstand the load it was designed for is
diminished. As more and more wood is destroyed, the structure be-
comes weaker. With poles, the location of the wood that is destroyed is
more important than the amount of wood destroyed. The outer 44% of
the pole radius contributes most (about 80%) of the bending strength.
Therefore, decay in the center of the pole will reduce strength substan-
tially less than if the outer shell is deteriorated. Decay in the above
ground portions of the outer shell of a well-treated pole is an indication
that the pole was decayed before treatment. This is why it is important
to specify "white wood" inspection of treated products to be purchased,
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