exposed -- big color difference.
However, some species are
known to be resistant to decay
fungi and insects due to natural
insecticides and fungicides in the
wood. Some of the best North
American species for natural resistance are black locust, red mulberry, Osage-orange, Pacific yew,
old growth bald cypress, catalpa,
all cedars, all junipers, mesquite,
white oaks, old growth redwood,
sassafras and black walnut.
Some common imported
hardwoods with good resistance
include ipe, old growth teak, Honduras mahogany, African mahogany, sapele, old growth teak, and
Spanish cedar. In the past, western
red cedar and teak have certainly
been widely used for outdoors.
In all cases, it is the heartwood
(colored in most species) and not
the sapwood (white in all cases)
that has the decay and insect re-
sistance. In addition to insect and
decay resistance, many of these
species do not shrink and swell as
much as other species.
Recently, we are seeing some
heat treated woods and some
wood treated with acetic acid
that modify the wood properties
and supposedly perform well
in some outdoor situations. We
also have some woods pressure
treated with a chemical wood
preservative (fungicide and
insecticide) along with a water
repellant…maybe the best choice
of all, except for the caution in
handling and working with such
wood (especially dust).
Hope this helps. Any follow-up?
QColor change of wood...why? The variation is killing us.
AAs you probably know, wood is made up of wood cells that look like miniature soda
straws. The cells are often around
1/8 to ¼ inches in length and
are very slender; the diameter
is about 1/100 of their length.
Depending on the species, the
chemical constituents of the cells
(both chemical in and on the
walls, plus chemicals within the
hollow space of the cells) can vary
greatly within a tree, from tree to
tree and from species to species.
It seems that many of the chemicals have some color to them and
also that these chemicals can be
easily oxidized and form a new
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