Horizontal limb splitting/barberchairing.

Treeaddict

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I was cutting a large heavy horizontal limb on a tulip poplar a few weeks ago. I’d usually piece it out in small sections but decided to try to coos bay the thing. I got maybe 15% in on the first cut on the far side far side and she started to go. This surprised me. Nothing has gone this quick with so little cut. Maybe 10% would be better. I just hid behind the trunk when it started splitting and it fell to the ground just fine.

It got me thinking (again) about the dangers of a BC limb. If the climber is on the trunk behind the limb they are out of reach, correct? Now the limb could hit the ground and spring back butt first into the climber IF the distance from the ground to the limb is short enough to favor that scenario.

The splitting could grab the climbers saw and take it with it potentially.

A fast cutting saw making an undercut and then racing through to top cut to “catch” up to the spilt is acceptable. Top cut placed closer to climber than undercut.

Is my thought process correct? This feels like a review of information that I’ve put in the back of my mind because I always favored the limb walk and small piece method so I kinda ignored some of the methodology and dangers as the info wasn’t used.
 
I'm thinking the coos bay was inappropriate for that limb/species. Assuming you got your 10% on each side(pretty iffy since it broke at 15% one side), you still have to cut it free. Seems like an inevitable barberchair. Maybe a tiny face and a bore would be better.

edit:
Also, on a horizontal limb, you're in the line of fire cutting a coos. You're arms are in a vertical position, and your body is somewhat precarious with limited avenues of escape.
 
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I'm thinking the coos bay was inappropriate for that limb/species. Assuming you got your 10% on each side(pretty iffy since it broke at 15% one side), you still have to cut it free. Seems like an inevitable barberchair. Maybe a tiny face and a bore would be better.

edit:
Also, on a horizontal limb, you're in the line of fire cutting a coos. You're arms are in a vertical position, and your body is somewhat precarious with limited avenues of escape.
I’d not try another coos on the poplar ever again. My second horizontal of that tree was an undercut (kerf, not face) and a speedy top cut. It went well. I was kinda off to the side, out of danger.
 
I was going to create a thread about this but saw this one. I recently whacked a bunch of big salt cedar limbs off. In the official work pics thread. It seems SC is similar to cottonwood. I faced some on the bottom, some I just kerf faced, some no face so they would swing drop. These were limbs mostly horizontal crossing the shoulder and one or two lanes of the road. Some taking most of my 24” bar. Fast saw/chain. All of them would take very little face before starting to pinch. I’d back cut, face would close, and hinge snap (pull) off clean and flush. No pull or flex like pine or fir. At some point it occurred to me that I might have been playing with fire risking a chair. I was in a bucket and we were dropping and dragging the limbs whole. I decided to GOL face/bore/trigger one. I was rewarded with a crushed hinge and pinched saw. Luckily had two saws. I probably could have kept boring and left thicker hinge but I went back to Kerf face and fast back cut. I went back and read FGTW on the subject and barber chairing doesn’t seem to be a big issue. I’m guessing limb fiber is less prone to split than trunk fiber, as least in some, most, or this species. I have found eucalyptus limb wood difficult to split by axe and trunk wood easy…sometimes. I know ash is very prone to splitting. Any more thoughts on the subject? Thanks
 
"Now the limb could hit the ground and spring back butt first into the climber IF the distance from the ground to the limb is short enough to favor that scenario."

True that. But even if you're high enough to keep clear of that scenario a limb that hits tip first and bounces back to the trunk can go beyond and take out a fence, a service, a window, a ground-man...

If I choose to execute a Coo's Bay on a big heavy horizontal limb / or arching spar, I'll get on top of either and cut them from above. You're using side cuts only. no undercut, no top cut.

When it comes to cutting any heavy structure in a tree a climber has to take extraordinary safety measures. Even if there's no targets below.
 
I was going to create a thread about this but saw this one. I recently whacked a bunch of big salt cedar limbs off. In the official work pics thread. It seems SC is similar to cottonwood. I faced some on the bottom, some I just kerf faced, some no face so they would swing drop. These were limbs mostly horizontal crossing the shoulder and one or two lanes of the road. Some taking most of my 24” bar. Fast saw/chain. All of them would take very little face before starting to pinch. I’d back cut, face would close, and hinge snap (pull) off clean and flush. No pull or flex like pine or fir. At some point it occurred to me that I might have been playing with fire risking a chair. I was in a bucket and we were dropping and dragging the limbs whole. I decided to GOL face/bore/trigger one. I was rewarded with a crushed hinge and pinched saw. Luckily had two saws. I probably could have kept boring and left thicker hinge but I went back to Kerf face and fast back cut. I went back and read FGTW on the subject and barber chairing doesn’t seem to be a big issue. I’m guessing limb fiber is less prone to split than trunk fiber, as least in some, most, or this species. I have found eucalyptus limb wood difficult to split by axe and trunk wood easy…sometimes. I know ash is very prone to splitting. Any more thoughts on the subject? Thanks
A drawing of the cut would be clearer. @Tree09 can help
 
The Coo's Bay cut is totally unconventional. It follows none of rules you ever learned about directional felling: limbs, spars or trees. Forget all that.

The Coos' Bay has no directional control. It's real worth in this work is in preventing massive woodpull and splitting.

For example, take a heavy limb. A real heavy limb. I mean a big, mean, nasty, heavy limb. The kind of limb you look at... and think to yourself, hmm... "How am I going to manage this?"

You have options here.

1. Cut the limb one third of the way in from the top. If it's really a big, mean, nasty heavy limb it's going to blow up, split-out, barber chair. All bad ju ju. Do not consider option 1.

2. Conventional wisdom's tell us to undercut said limb one third of the way in. If said limb is indeed a big, mean and nasty, heavy limb then it will set down and trap the saw in the cut long before you even get one third of the way in. Not good either.

3. Get above said limb. If it is indeed a big, mean and nasty ol' heavy limb, because it is wise to follow this advise. Secure your perch with climbline, lanyard and foot holds. Then reach down with your saw and sever the left side of the stem perpendicular to its main axis. (favor) Yeah, cut the stem one third of the way in. Generally speaking, if said limb is not previously checked, cracked or rotten then nothing bad should happen.

How can this be? You got that big, mean limb cut a third of the way in on one side, and nothing bad has happen. WTF?

Don't get cocky now, because it's all going to come to play real soon.

Now, readjust your lines and secure your perch again, this time to aid reaching down and severing the other side of the stem, just opposite of the other cut and perpendicular to the main axis (favor) of the stem. Full bore, Do not hesitate... one third of the way in. and finish with a quick wisk of the lower bar, full bore, across the tension side of the holding wood, and hold firm to the saw to pull it out quick.

If you judged the situation properly that big, mean, ol' nasty heavy limb will part its stem with minimal wood pull, like a pussy cat.

The Coos's Bay cut does not come without a long list of caveats. Too long to cite them all here.

But in nutshell, when it comes to cutting any heavy work. Be it a limb, top, spar or tree, understand, you're entering into a realm where anything bad can happen even if you do everything right! I'm serious.

As long as you understand that you stand a better chance coming out as the victor rather the victim.

In any case, if you don't feel sure and certain about it then you better go to plan B. Which often comes down to "piecing it out".

A Treeman's Wisdom's. There's a million of them.
 
I like the T style.

IMG_0667.jpeg

Thinking more, specifically the face cut. What often causes a chair is when a face closes after the crown already has momentum. A kerf face does not allow much momentum to build. A very open face should let you get a good portion of the limb cut before the face closes…but as I type this and think through it, I realize the other contributor to ‘chairing is flex. The middle or hinge wood is flexing and the back wants to stay straight. Depending on the species/fiber they may separate = chair. If one only does a kerf face, and maybe starts the back cut slowly until the kerf closes, there will be no momentum. Also, there is very little bending. All the force in the upper part of the limb is tension, not bending. Then finish quickly.

Another variation is to cut the triangle Coos kinda as if overbucking on the ground. Drop the powerhead and cut the close side at an angle. Then raise and roll it over to the other side (here is the actual overbuck) and drop the tip to cut at an angle. Then go full bore down and back towards yourself. I’ve seen some tree guy do it, can’t remember who. Maybe GOT. This is especially helpful with a small top handle that’s not particularly fast. I would definitely do this if I had been using my 2511. I was using a ported 346, so I just went for broke.
 
All about the Coos Bay is covered here...well, a lot anyway :).

 
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Not a Coos Bay, that's a triangle cut...I think?
Oh, yeah. Coos bay is more just a Mohawk, forgot.

I like the T, but the triangle is fast. Basically just bucking. I like both better than the Mohawk for their directional control. . I have a big lead still hanging off that downed oak I’m going to try to swing a little.
 
Don't be hatin' on the Coos Bay because it doesn't give directional control :). In fact, it gives complete directional control...directly to the lean :D.

It is what it is, and that's to allow you to get a very heavy leaner off the stump (or horizontal limb off the tree, as the case may be) without it blowing up in your face, like no other felling cut does.
 
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