Thneed Weekly – Week 2014 – 28

Welcome to another week of Thneed Weekly. The Penguin in charge of writing these has been super busy and is getting behind. So this week we are going simple.

D-Tape…  What is it?  How does it work?

Well it is magic.  Thanks for joining us for another Thneed Weekly…

OK not really.  A D-Tape or a Diameter Tape is a measuring tool used by natural resource professionals to measure the Diameter Breast Height (DBH) of a tree.  Now that is the typical use.  Having measured many felled trees you can use it to get the diameter of any circular object.

You are thinking well big deal we all know that the distance around a circle is related to the diameter.  Specifically.

Circumference = PI * Diameter

So let’s move some stuff.  If we know 2 out of 3 of those all we have to do is figure out diameter.  Meaning…

Diameter = Circumference / PI

So all that needs to be done is you measure the distance around and divide by PI.  SIMPLE!  Well foresters like to make life easy and having to remember 3.14159265359879323 is tooooooo much effort.

So a D-Tape while it is measured in inches (or CM) those markings occur every PI inches.  This eliminates having to do the math.  While this seems simple looking back on it no doubt early cave foresters had to come up with this idea of making the tool do that.  No doubt an AH HA moment.

More next week…