What causes a tree to barber chair

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strtspdlx

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I've been having an issue lately with a few larger trees barber chairing not necessarily bad but it could be worse. They're probably 30ish" trees give or take 10-12" (I'm not good at visual measurements without a tape measure). And when they split its probably about 2-3' up. I have no idea why they do but if someone could give me insight into how to make it less likely to happen I'd appreciate it.


Regards-Carlo
 
Could be a lot of things. It could be the heart wood is rotten, your face cut isn't deep enough, too much lean for a conventional face and back cut, failure to cut the sap wood on both side of large diameter trees...etc.

Before you can prevent a barber chair you need to know and understand what's causing it.
 
I've been having an issue lately with a few larger trees barber chairing not necessarily bad but it could be worse. They're probably 30ish" trees give or take 10-12" (I'm not good at visual measurements without a tape measure). And when they split its probably about 2-3' up. I have no idea why they do but if someone could give me insight into how to make it less likely to happen I'd appreciate it.


Regards-Carlo
Why don't you post up some pictures of the before and after.


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I wasn't thinking about it last time I cut. And all the evidence is already gone. Next time I cut hopefully it doesn't happen but if it does I'll be sure to snap some photos.


Regards-Carlo
 
Could be a lot of things. It could be the heart wood is rotten, your face cut isn't deep enough, too much lean for a conventional face and back cut, failure to cut the sap wood on both side of large diameter trees...etc.

Before you can prevent a barber chair you need to know and understand what's causing it.

That's what I'd like to learn. I
Understand it's the tree splitting because of the hinge. But what in the hinge causes it? Is there a way to setup the hinge so it won't do it? What preventative measures can I take and how do they effect it to prevent it from happening. I've only been cutting for 2 seasons. So needless to say I'm a newbie but I need to learn before I get hurt.


Regards-Carlo
Edit. You refer to sapwood. What is that? And to the best of my knowledge the trees where solid. No rot. The one that was dead as a door nail did t barber chair either. And I put a tiny mouth on it. Maybe and inch deep tree was probably 24" or so
 
Sometimes boring and back strapping the back cut can help from barber chairing others are just a bit too hairy and make you pucker up.


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Carlo...if you have leaners and you can fall them with the lean, this cut works pretty good. The triangle works better for me 'cause it's easier to match up the cuts but either one will work.
hpqscan0001.jpg
 
Barber chair is for sure bad - people are killed every year from them!

Are you staying in the cut long enough? If you leave too much of a hinge it can barber chair.
What tree species are you cutting?
 
Oak ,pine, and 2-3 species that I don't know what they are.


Regards-Carlo
Edit. Valley firewood I didn't answer all questions. Once I get them dropped my hinge is only 1" to 1-1/2" wide. And I full gas after it cracks until it swings down. I only had 3 of probably 20 do it to me but it still makes me very nervous. Most split straight up and went back away from me but I'm waiting for the one that hits me.
 
All good advice given already. The mechanics behind it is one side of the trunk is in tension and the other side is in compression. At the plane where the forces of compression and tension meet there is a shear force. Wood fibers are poor in shear force so when they fail you get separation at that plane, hence barber chair. By using a bore cut you can remove that area where the two opposing forces (compression/tension) meet and mitigate the potential to chair.
 
I use the triangle cut Gologit posted on any tree that has a good lean to it , Be careful not to walk behind the tree when making the 2 side cuts ,i put a face in first ,then nip the 2 side triangle cuts ,a longer bar is nice for this ,keeping your body farther away ,after the side cuts are made ,the pressure is relieved from the barberchair ,then make a reg back cut where the point of the triangle is .

Here is an example on a small alder stump that had a good lean to it after it was cut coos cut 027.jpg .
 
Some species are prone to chair like ash. Even if there is no lean. Which could be your unidentified species. i have seen people do to shallow of a face and to small of an angle cause the tree to chair when the face closes before the hinge lets go.
 
I use the triangle cut Gologit posted on any tree that has a good lean to it , Be careful not to walk behind the tree when making the 2 side cuts ,i put a face in first ,then nip the 2 side triangle cuts ,a longer bar is nice for this ,keeping your body farther away ,after the side cuts are made ,the pressure is relieved from the barberchair ,then make a reg back cut where the point of the triangle is .

Here is an example on a small alder stump that had a good lean to it after it was cut View attachment 437567 .
So you do the face cut, then the 2 angle cuts. Are the angle cuts just a straight cut or wedge? Also is there a back cut in there to release the tree or the 2nd angle cut acts as the back cut?
 
I am not the greatest sharpie artist ,but hope this helps
Cut 1 is the face ,i personally use a humboldt
Cut 2 ,first side cut line it up with the hinge in the face
Cut 3 ,second side cut ,connect hinge with the first side cut ,now the triangle is made
Cut 4 , The final reg back cut start at the tip of the triangle you made ,when you hear stuff popping in the back cut ,run away like a little girl ,because the tree is going over
A longer bar is safer when cutting any chair prone tree ,cutting with the tip end of the bar ,it helps keep you more away from the tree if it decides to chair out
What the side cuts are doing is relieving the pressure in the log that wants to chair out ,once you cut those out ,it is much less prone to pop with that material gone .
The stump i posted was leaning about like the drawing ,and you can see how it ripped the fiber guts out going over slow vs chairing out .

On the question on the side cuts ,they are just one cut strait ,no wedge to them ,only wedge is the face .
coos cut 002.JPG
 
I am not the greatest sharpie artist ,but hope this helps
Cut 1 is the face ,i personally use a humboldt
Cut 2 ,first side cut line it up with the hinge in the face
Cut 3 ,second side cut ,connect hinge with the first side cut ,now the triangle is made
Cut 4 , The final reg back cut start at the tip of the triangle you made ,when you hear stuff popping in the back cut ,run away like a little girl ,because the tree is going over
A longer bar is safer when cutting any chair prone tree ,cutting with the tip end of the bar ,it helps keep you more away from the tree if it decides to chair out
What the side cuts are doing is relieving the pressure in the log that wants to chair out ,once you cut those out ,it is much less prone to pop with that material gone .
The stump i posted was leaning about like the drawing ,and you can see how it ripped the fiber guts out going over slow vs chairing out .

On the question on the side cuts ,they are just one cut strait ,no wedge to them ,only wedge is the face .
View attachment 437692
Awesome, thank you. I put that one in the tool bag.
 
There are a lot of good posts here on how to cut trees that are obvious candidates for barber chairing, but if you cut enough trees eventually you will have one barber chair that is not leaning or showing any visual signs that it would. I have had perfectly strait and sound larch barber chair 35 feet up and land 30 feet back from the stump, had to pack out a co-worker with a broken neck from a lodgepole barber chairing and had thousands of trees with no lean or rot start to barber chair. Here are a few tips that I always use to prevent(or stop once they start) the non-obvious trees from barber chairing:
- Always make a deep enough face cut so that when the tree is falling and the face closes it will not slow or prevent the tree from continuing to fall.
-unless there is a really good reason to get a long ways away from the tree always finish your cut and do not start to walk away as soon as the tree starts to fall. The main reason for a tree to barber chair is when it starts to fall and has momentum or a lot of weight in the top and something at the stump (not cutting enough holding wood, having a shallow face) starts to stop the tree from falling. This puts an immense amount of vertical splitting pressure on the tree trunk at the point you stopped cutting. I always stay cutting until the tree is going right where I want it to and is well on its way before walking or running away.
-obvious one but always cut a clear escape path or multiple escape paths from the base of the tree. I like to have my main one go at a 45 degree angle back and away from the direction I am falling the tree.
-If the tree starts to fall and you notice it start to barber chair cut as fast as you can!! If you can cut enough wood to make the forces holding the tree up on the stump less than the forces cracking the trunk vertically the tree will stop barber chairing and fall. I can typically prevent 95% of barber chairing trees this way but it is absolutely essential that you are able to tell when it is to late and time to quit cutting run as fast and far from the tree as you can. -Always cut with a sharp saw! Even if it is the last tree of the day stop to file or switch chains. A dull saw makes the above tip useless and will just waste valuable time that could be used to get away from the tree.
-Watch your limb weight...it can create every bit as much force on a tree as a heavy lean.
-one last one is once you decide to run go twice as far and twice as fast as you think you need to they happen so fast and can land way farther from the tree than you could imagine.
Happy cutting!!
 
I was on YouTube searching around and noticed a lot of people plunge cut their back cut and leave a trigger on the backside. Supposedly this lessens the chance of a barberchair as your hinge is already setup. Assuming that the hinge is setup and I plunge cut and leave that trigger is this a safe way to fall a tree wether it is likely to barberchair or is not?


Regards-Carlo
 
It lessons the chance for it to chair because you created some distance between that plane where one side is in tension and one side is on compression. It's a very good way to reduce the chance of chair but it also creates some new risks. Like, if you don't leave enough material in your trigger it could fail and the tree falls before your ready. If you go to cut the trigger and it pulls the fiber from the stump it could take your saw with the tree. It could pull a chunk from the stump if the stump fails. There is usually a tremendous amount of tension in that section of wood.
 
It lessons the chance for it to chair because you created some distance between that plant where one side is in tension and one side is on compression. It's a very good way to reduce the chance of chair but it also creates some new risks. Like, if you don't leave enough material in your trigger it could fail and the tree falls before your ready. If you go to cut the trigger and it pulls the fiber from the stump it could take your saw with the tree. It could pull a chunk from the stump if the stump fails. There is usually a tremendous amount of tension in that section of wood.
Yes and if it takes your saw ,let it go ,things can go wrong real fast .
 
By using a bore cut you can remove that area where the two opposing forces (compression/tension) meet and mitigate the potential to chair.
I stated something similarly once, and a member here (pelorus) pointed out to me that you are simply shifting the neutral plane to the hinge. Not that it affects the conversation much, just thought it was a good point.

The right amount of lean and top weight, coupled with a poorly cut face can result in a barber chair in spite of a bore cut.
 
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