The stick trick for estimating tree height for felling

[Tim Harrigan]

Had a nice weekend so I took my camera out with me and demonstrated the stick trick for calculating where the top of the tree will hit. Good trick to know if you want to protect other trees in the area.

[video=youtube_share;aQv13Bn4hAc]http://youtu.be/aQv13Bn4hAc[/video]

[Donn Hewes]

Tim, I think you videos are great and will really help folks. I have a funny story along this line. I was dropping ash recently I and it was a delicate piece of directional felling to get it down between nice young maples. I looked out and said, oh I will aim right for that old apple that will bring it down right were I want it. I hit that old apple with 10′ of the top. Just about ruined it! They say I should take them out any way as I have been planting a young orchard nearby, but I must confess I wasn’t planning to go that far. thanks, and talk to you soon, Donn

Too bad I wasn’t making a vid on perfect directional felling!

[Does’ Leap]

Hi Tim:

Thanks for the video. I learned this trick when I went through Game of Logging and could not remember the process. Aside from saving nice regen, this technique should help prevent future hang-ups for me.

Cheers.

George

[Tim Harrigan]

Donn, that would have been a great video, heavy sound editing I suspect. It is interesting when the tree is half way to the ground and you realized you might have over-looked something. George, I like this trick because you can use any length for the sides of the triangle and you don’t have to measure from a specific distance, just adjust your location until everything lines up. I did set my camera back a couple of steps, though. Was not willing to risk crushing my camera to make a point.

[Anonymous]

Tim, here in the northeast we would call you one wicked smaht man!

[mink]

tim i like the lil tune you chose for your video.jen like the reginal accent…lol

[Andy Carson]

This is such a great trick using tools you have in hand already. The math works out pretty well when you form a right angle between the line from your eye to the top of your hand and the goad. If the goad tips forward or backward, though, the estimate will be off. Again, I know this is just an estimatation tool, but if it was really important to get this exactly right, I might be tempted to use a makeshift sextant made from a straw to sight through, a grade school protractor, and a string and weight to use as a plumb bob (see below). These things cost less than $10 (and might be hanging around the house already) and it still fits in a bag of tools. Sight the top of the tree (through the straw) at 45 degrees and you have the same height estimation technique used by Tim without the potential confounders brought on by assuming a right angle by eye and reconing.

[IMG]http://minnesotahillbilly.files.wordpress.com/2008/12/surveyors-compass-and-815-cent-sextant.jpg?w=490[/IMG]

Note: I am not saying that Tim’s method doesn’t work, I am just thinking about how accuracy might be improved in situations where this was important.

Note 2: Using the sextant method also allows you to estimate height if you are at a significalty different elevation than the base of the tree. This involves trigonometry though, so you would have to pack a calculator too. In the example below, the distance from the tree (D) has to be known. One thing I really like about using a 45 degree angle is that one does not have to measure the distance from the tree as D=A, so the measure is essentially unitless. It is clear in the illustration below that the distance (B) is pretty small and can be ignored if you are on mostly flat ground. On a slope, though, this is not so true. One could calculate B as a percent of A and remain unitless, but on a steeper hillside I would probably just bring a 100 foot long string and a calculate off of that, with D=100. On a shallower hillside I might make a mark on the tree at 6 feet off the ground and estimate B by sighting from your current position to the tree on the level (as judged by the sextant). The 6 foot mark would let you gauge how much more of less B is compared to the measure. (IE, I am sighting about twice as high as my mark, so B is about 12 feet). Then you can step back 12 feet and you still don’t have to bring a string.

Note 3: The illustration above makes clear that even on flat ground the angle between the eye and base of the tree, and the base of the tree is not exactly 90 degrees, even on flat ground. For tall trees on flat ground this is probably not that big of a deal, but greater accuracy would be achieved if one sighted at the tree in at 5.5 feet off the ground (or whatever your eye height is), and then stepped back 5.5 feet once the measurement is taken. Again, I know its just an estimate, but this increases accuracy and is easy to do.

Note 4: I just made something very simple very complicated, didn’t I? 🙂

[Tim Harrigan]

@Countymouse 39967 wrote:

Note 4: I just made something very simple very complicated, didn’t I? 🙂

We’ve come to count on that. :rolleyes:

[Jim Ostergard]

Well said Tim. I have used the stick method for years and have missed power lines and been able to figure a spot where the top will fall extremely closely. It takes some practice for sure but an easy and useful tool the old stick and it ain’t too comples. Tim Ard of Forest Applications makes a handy pocket tool also.

[Eli]

I have to show this to my brother last year we cut 30 pines 40 to 50 feet tall off a guys lawn. I got whipped a few times with branches I had a tractor with a rollbar however I remember him telling me I was clear. It could be an older brother thing couldn’t tell if he was laughing through all the brush. But that would make me wicked dumb.

[Oxhill]

Nice video! How many cameras did you go through practicing?

[Tim Harrigan]

I gave some thought to that. I took two giant steps back from where I thought it would hit, worked out OK.

[Author]

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