One of my favorite tools, that I bought for around $40 at least
38 years ago, is a 16-inch Swedish increment borer used for
extracting a pencil-thick core from a tree. If one is lucky and
the coring device hits the very center of the tree, then a
fairly accurate age of that tree can be determined. The
tendency is for the borer to enter the tree either to the left
or right of center. Now some guessing is required to estimate
that tree's age. At least you can get an idea of the rate at
which that specimen is growing outward.
The species of tree from which I have more cores than all other
trees combined is the American arborvitae, also commonly called
the northern white cedar. The wood of this tree is soft, very
easy to core into, and the annual rings of the core that has been
removed are easy to see and to count. Once a core is dry I glue
it to a strip of wood. Now I can used a very sharp instrument,
such as a razor blade, to carefully remove a thin slice from the
entire top of the core. Wiping the core with some boiled linseed
oil causes the annual growth rings to show up very nicely.
For years I've favored the name of arborvitae, meaning "tree of
life," over white cedar. You'd be surprised at the number of
lowered jaws and blank stares I encounter upon stating that there
are no true cedars native to North America. The usual reply is,
"Well, if these aren't cedars, what are they?" I guess the best
way to accept the name is by assuming that if "cedar" was good
enough for dad, granddad, and great-granddad, ad infinitum, it
has to be good enough for the present generation.
Donald Culross Peattie summed it up well in his excellent book,
"A Natural History of Trees of Eastern and Central North
America." He said, "If this one is arborvitae to the gardener,
the nurseryman and botanist, the lumbermen are merely sorry for
city folks who cannot recognize a cedar when they see it."
Our arborvitae trees belong to the genus Thuja (THEW-ya), an
ancient name of some resin-bearing evergreen. Its species name,
occidentalis (ok si-den-TAY-lis), refers to its western location
in the world in contrast to those of eastern Asia.
Native Americans of this region called this pungent aromatic tree
'Oo-soo ha tah' meaning feather leaf. French voyageurs in North
America learned from the natives during the late 1500's that a
potent tea brewed from the leaves and bark of this tree, rich in
vitamin C, cured scurvy like magic. This quality perhaps led to
its being the first North American tree to be introduced to
Europe. There is a record of one planted in Paris in 1553.
The Indians knew the fine qualities of the arborvitae as shown in
their lightweight durable canoes. The ribs, prows, frames and
gunwales of these crafts were made of this wood. The annual
rings, or yearly growth thicknesses, sometimes pull apart in
living trees due to "wind shake." The Indians, knowing this,
used a stout club to pound the cut lengths of the wood in order
to loosen these annual increments into thin flexible strips.
One of the arborvitae trees I cored revealed that the tree was
hollow due to a heart-rot fungus. Although the core I extracted
was only three and three-fourths inches long, it contained 150
annual rings. This averages out to about 40 years of growth per
inch of diameter. In other words, that tree was growing
outwardly at the rate of one-fortieth of one inch annually.
Using extrapolation, and taking into considerabion the diameter
of the living tree, I estimate it to be at least 320 years old.
It may have begun its growth in around 1678!
Arborvitaes apparently like the glacial soil of the Lake Michigan
shore area in northeastern Wisconsin. I can vividly remember my
boyhood days in Kewaunee of hiking along the shores, both south
and north of the city, and seeing large stands of beautiful
arborvitaes growing in the steep gullies leading down to the
lakeshore.
Three of the top ten record-size arborvitaes in the state are in
Manitowoc County bordering Lake Michigan. In fact the number
four tree in the state, growing in Manitowoc county, has a
circumference of 161 inches (13 feet 5 inches), equal to the
record arborvitae in Douglas County, in the extreme northwest
corner of the state. However, the Manitowoc tree is only 62 feet
tall compared to the record-holding tree's height of 89 feet.
The national record arborvitae grows in Leelanau City, Michigan,
has a circumference of 18 feet and is 113 feet tall.
Through the years those trees having clockwise spirals to the
trunks and branches in the northern hemisphere, or in other words
spiral toward the right as you face the tree, are better able to
cope with windstorms than those trees whose trunks and branches
spiral in the opposite direction. They would have a much greater
tendency to snap and break during storms.
Another incredible feature of the arborvitae is its ability to
grow infinitesimally slow, depending upon the site where the tree
is growing. Professor Douglas Larson, botanist at the University
of Geulph in Ontario, working with a group of graduate students
making up the Cliff Ecology Research Group, have concentrated
their studies upon arborvitae trees growing out of the steep
Niagara Escarpment along the east side of the Bruce Peninsula in
Ontario.
The oldest dead arborvitae they have discovered thus far was
1,653 years old when it died. Equally amazing is the fact that,
through radiocarbon dating, that ancient tree died over 900 years
ago, around 1082. What has puzzled the scientists is the
astounding durability of this wood.
These "vertical forest" trees, exposed to a range of at least 130
degrees F. temperatures during a year, grow infinitesimally
slowly. Much study of how these ancient trees can obtain
sufficient nutrients, with the help of algae and fungi growing
within the bedrock, is being studied intensively by this Bruce
Peninsula group.
Call it white cedar, arborvitae, or tree of life, few other trees
can match it. Beauty of form, durability, fragrance, historical
importance, long life, usefulness to people and wild animals,
this tree has them all!
Several features of the arborvitae have fascinated the experts
for a long time. One is the tendency of the trunk to spiral to
the right as the tree grows. It has been through the work of two
Norwegian foresters that it is now believed that arborvitaes and
other species of evergreen trees have for centuries responded to
being broken and twisted by the wind. Arborvitaes, for example,
growing in the northern hemisphere naturally develop more
branches and needles on their sunny south sides.
Also see:
More information on this topic is available at:
This column appeared in the Door County Advocate on 11/27/1998.
© Copyright 1998 Roy Lukes. All rights reserved.
