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My forestry
career started in 1973 with a job working for Crown
Zellerbach Corporation in Tillamook, Oregon. Having just
finished a four year degree in Forest Management from Oregon
State University, I was ready to see the “real world” of
forestry. My fellow foresters told me to set my compass
with a declination of 20 and a half degrees east. As is
often the case, I left my compass set with that declination
for many years.
While my compass
declination was static over the years, the actual
declination has been slowly and continually changing. I was
actually quite shocked to see that the present declination
is 17 degrees for my area. That’s a difference of 3 and 1 /
2 degrees! Not very conducive to accurately using a compass
in the field.
The original
declination value was obtained from the USGS quad maps. As
the maps dated to about 1965, the declination error was
present at the beginning of my forestry career and was
getting worse over time. It is common practice to use the
declination listed on the USGS quad maps when working in a
new area. Fortunately, there is a much better way to obtain
accurate declination values now; via the internet.
Here’s the
address to get onto NOAA’s web site with declination
information:
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