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NickfromWI
04-07-2008, 08:18 PM
I was in the mountains yesterday checking out trees. I wanted to know the DBH, but had to tape on me. I can guess close enough (I think) but I wanted exacter numbers.

Rather than hauling around a measuring tape, I came up with this:

MasterBlaster
04-07-2008, 08:23 PM
I have two logging tapes in my toolbox...

NickfromWI
04-07-2008, 08:26 PM
I took a 13' piece of the NER throwline (zing it would work great, too). I spliced an eye one one end. This is the "zero-eye" mark. Then I tied an over hand knot 3.14159 down the rope. This comes to 37 11/16ths of an inch.

I went down another 37+ inches and tied a double overhand. Went again tying a triple overhand, and one more time, tying a quadruple overhand knot.

So now I could walk up to a tree, feed the tail end through the zero-eye, then pull tight. I find the last knot. If the first overhand knot is even with the zero-eye, then the tree is exactly 1' DBH.

If it's somewhere between 2 knots, you have to estimate.

I took it a step further. I put 5 marks (tiny whippings) between each knot. They are color coded- red, orange, yellow, green, blue. The colors of the rainbow. There is one every 2" x pi. This comes to 6 1/4". Now, I can look through and estimate DBH to the nearest 2"!

In the picture above, that Liquidambar styraciflua has the orange mark at the zero-eye. That tree is about 1' 4.5" DBH.

It seriously took me about 2 hours to make the whole thing with whippings and everything, but I have a neat little tool that will take the guess work out of measuring trees

love
nick

note- I wanted a lighter weight option than carrying a measuring tape. Back-country hiking is best when you have less to carry!

NickfromWI
04-07-2008, 08:28 PM
I weighed it and it comes in at .36 ounces!

Paul B
04-07-2008, 09:25 PM
hm, cool for recyclers but as MB said, I have a D-tape in my truck, and a 50' reeltape that I can do the math on if pressed to measure DBH the old fashioned way.

rumination
04-08-2008, 04:53 AM
I weighed it and it comes in at .36 ounces!




You have attained total rope geekdom Nick. :P

But it IS a cool idea, and nicely made too.

OTGBOSTON
04-08-2008, 06:35 AM
cool! I have thought about making a sling for my SRT anchor with DBH markings on it just for S+G.