Finding the Top   Edward Frank
  Dec 29, 2006 18:41 PST 


Finding the top of the tree while scanning with the rangefinder is one
of the art forms of tree measuring. I am still working on it. Will,
Bob, Dale, and others can whip out a tall measurement and be done while
I am still looking.

If you hold the button down right the rangefinder will go into scan
mode. Move it back and forth across the area you think may have the
highest top. In a series of branches at about the same angle upward -
the one that is the farthest away by the readings is the tallest of the
group. Look for tops back into the tree farther when viewing from the
side rather than just looking at the branches closest toward you, even
though they may appear to be higher.

You also need to be sure you are actually reading reflections from the
branch you are looking at rather than an intervening branch. Scanning
back and forth helps you decide if you really are hitting the branch you
are pointing at. Look for wider openings to get a better shot free
from any intervening branches.

Walk around the tree and look for shots from different angles. Look for
different high points. All are not visible from the same position. I
have been encouraging Bob L. to try and write a list of suggestions on
how to best explore the crown of a tree, but so far no luck.

Anyway, perhaps you found the highest point after all.

Ed Frank
RE: Back to Don   Don Bragg
  Dec 30, 2006 05:03 PST 


The ability to use a continuous scanning mode with these
lasers really helps to find the highest of the high points. As I recall
when we visited that big cherrybark oak, I spent quite a bit of time
scanning heights in the 80s or 90s, before I finally hit some higher
branches that made 100+ feet. It sometimes takes a lot of patient with
these large crowned trees, but rest assured that with the sine method,
unless you are measuring the wrong tree, your estimates will never be
too high. I have just come from a forest with a tuliptree claimed to be
180+ feet tall that is actually about 135 feet...

Don Bragg
Will Blozan write in Tree Measuring Guidelines for the Eastern Native Tree Society:

· How do I explore the crown architecture?

“Skate” the laser over the surface of the crown and in “nested” pockets and places you may not expect a high part to be. The highest point may be well below what appears to be the tallest part. Look for the farthest distance first, then the highest angles with far readings. Once you become familiar with a species and its architecture, you will know how to narrow your search down.