Northeastern Forest -- Sugar Maple Question

Ron Wenrich woodtick at lebmofo.com
Fri Jan 9 17:32:27 EST 1998



ForestFair wrote:

> My _uneducated_ guess is 100+/- years.  They're from 16"-26" dbh.  If it stops
> raining, I'll go up this weekend and count rings.  The harvesting is stopped
> until the ground freezes again.
>
> It's an appearance defect, and it affects usability only for aesthetic reasons.
>  With the exception of the darker color that is apparent only after cutting,
> there's no other sign of abnormality.  Our consultant and the loggers didn't
> know until they started cutting.
>

Found this in TEXTBOOK OF WOOD TECHNOLOGY by Panshin & DeZeeuw, pg. 327

    "Natural and Chemical Stains
    1.  Mineral Stains.  This term has been loosely used in the trade to denote
stains of various kinds in lumber without regard to their origin.  In a more
restricted sense,  the expression mineral streaks or mineral stain should refer to
the olive and greenish black, usually lenticular, areas common in otherwise normal
wood of hard maple and occasionally also in other hardwoods.  This discoloration is
traceable to dark globular masses of the material responsible for the color, found
mainly in the ray cells and in the vessels.  These extraneous materials are
apparently responsible for the higher mineral content of such areas compared with
that of the surrounding wood, averaging 5.2 % ash content in hard maple, as
contrasted with only 1.2% in normal bright wood.  When wood containing mineral
streaks is seasoned, cracks frequently form where the discoloration is deepest.
Millmen contend that wood with mineral streaks is harder than normal stock and that
is has a pronounced dulling effect on cutting tools.  The discoloration caused by
mineral stain are also considered objectionable because of the problems such local
stains present in wood finishing.
    No acceptable explanation has yet been found to account for the development of
mineral streaks.  There is some evidence that the mineral discoloration may be
initiated by obscure injuries, which in some manner interfere with the normal
physiological functioning of the cells proximate to such areas.  Likewise, a
possibility of bacterial infection as a contributing cause to formation of mineral
stains cannot be dismissed."

They also went on to say about extraneous material in the cell wall. "When the ash
content is above normal,  silica may often be the principal component; however, a
notable exception occurs in the mineral streaks of hard maple which are unusually
high in manganese."

Just out of curiosity, are your loggers local?    How did the local loggers bid on
your sale -  high, low?  I've seen local loggers be low bidders on sales, since
they knew more about the timber quality than loggers from outside the area.
Usually, they're right.

RDW




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