might call “unnatural” or “unusual”
heartwood, as it is not age related,
we often call this wood “pathological
heartwood,” because it its formation is
triggered by a pathogen.
The wood in this enclosed area
is often subject to severe weakening,
due to the action of the pathogens,
and may even dry out somewhat. This
heartwood may even have some cracks
develop in the living tree. Now, when
the tree is sawn into lumber, we will
see this pathological heartwood as
brown, often dark brown, areas. After
drying, even under normal drying
conditions, the pathological heartwood may have open cracks that result
because the damage existed in the
living tree or because the wood was so
weak before drying began.
In short, cracking, often called
checking, is inherent in brown maple.
QWhat causes small little bumps (we might even call them pimples) that we can
We have done this veneering and
see in our gloss finish of
veneer wrapped over MDF? They are
hard to feel with our hand, but are
real obvious by eye. When we examine
the pimple, we find that the veneer
seems really thin at that spot and the
MDF core is right below the surface.
finishing for quite some time and only
now are we seeing the problem.
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In some species, conversion to heartwood might
begin in three years and in others, like maple, in
50 to 75 years.
See more at the Wood
Dr. Knowledge Center
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