[TowerTalk] Finding the height of trees

[Kurszewski Chad-WCK005]

KC0XU wrote:
> Now, it has been more than a few years since I was a boy scout. But the
> trick we used was to stand a pereson of known height next to the tree or
> whatever, then back off a approximately a couple of times the heighth of
> the tree, hold a pencil or similar object at arms length and mark the
> hieghth of the person with your fingers such that the length of the pencil
> visible above your fingers appears to be the same heighth as the person.
> then use that length to count how many times the heighth of the person the
> tree is. Takes a lot longer to explain without pictures than to do. A
> stick
> or board of about 5 ft length could be substituted for the second person.
> 
This is how I've seen it done (as above).

But instead of using a pencil, just use a 12" ruler.

Precisely:
Have a person of known height (for example, 6') stand
at the base of the tree.  (Or, have that person hold
or point to a point on the tree that is 5' or 6' from
the ground.  We'll stick to the 6' person for now.)

Then walk away from the tree a ways.  Take the 12" ruler
and hold it out in front of you.  Move the ruler closer
or further from your eye so that the 6' person is exactly
1" tall on the ruler.  Then, holding the ruler in that
position, see how tall the tree is against the ruler.
For example, the tree is 7" tall.

Now simply take the tree measurement (7") and multiply it
by the known height (the 6' person) and you get:
7 * 6 = 42'.

Chad WE9V


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