Safe rope use to guide a falling tree.

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ken morgan
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Gotta admit I have been extremely lucky when winching trees over but to be honest I was just adding a little extra pull to one side so all my trees to date knock on wood I’ve fallen exactly where I wanted them. my real concern is and always will be a tree that is rotten in the middle and barber chairs on me that’s what really scares the snot out of me. Pros make it look easy but in reality it probably the most dangerous thing to do on a day to day basis
 
onedash

onedash

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i got a more power puller that has worked great so far. If a tree isn't leaning in the direction i need it to fall It gets a rope and usually the more power puller. I got the monster straps to attach to anchor tree. i've gotten pretty good at getting the trees to land where they are supposed to.
 
pdqdl

pdqdl

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I have a bunch of tall poplar that are nearing end of life, and are leaning the wrong way to fell normally without putting house, barn, or shed at risk.

Check my calculations:
A 2 foot diameter poplar with have a stump area about 3 square feet. 80 feet tall. Let's assume that the branches make up for the trunk taper and for weight purposes it is a cylinder. 240 cubic feet.

Wet poplar at 40 lbs/cuft gives me a mass of 9600 pounds -- about 5 tons

If it leans 15 degrees, (over estimate) then there is about 25% of that load is in the horizontal direction. 2400 lbs.

I have 150' 3/4" nylon solid braid) rope with a rated breaking strength of 20,000 pounds in new condition, with an eye splice on either end.

My thought is put a messenger line into the crown, draw the rope up and over, bring the eye down, and pass thorugh. Attach the other end to my tractor (Deuzt 55 hp -- weighs about 3 tons)

Coefficient of friction on a tractor tire on firm soil is aobut .5 So maximum force tractor can put on rope is about 3000 lbs.

So use the tractor to tension the rope until wheels start to skid, OR it stretches 8% (Estimate of elastic stretch. I have an inquiry with the rope maker for this number)

My plan was to make the wedge cut first, then tension the rope, then make the back cut.

Is this a reasonable approach?

I haven't checked all your math, but I'm pretty sure that the branches do far more than make up for the taper. It is startling how much more the leaves and twigs weigh when compared to the mass of the branch that supports them. Furthermore, the distance they are displaced from the centerline makes a huge difference.

I agree with others that you are planning on pulling way too hard.

I think there are a lot of things you haven't considered. I'll just mention a few.
  • I think 5 tons is considerably light for an 80' tall poplar. BTW: how did you measure that height?
  • The higher you attach your rope, the weaker the wood will be. Poplar breaks real easy, by the way. You are likely to break the crown out if you put it too high and pull too hard.
  • The higher you hang your rope on the tree, the more weight you will take off your tractor, especially if you attach to the rear drawbar. Traction will be reduced! Where you tie to the tractor can dramatically affect what happens when you pop the clutch as the chainsaw operator hollers "Go!"
  • How are you going to tie on to the tractor? I've seen many a rope broken wrapped around hard steel.
  • What knot can you tie in nylon rope that won't weaken the rope or even fuse under pressure? (Nylon is famous for doing that, you know)
  • The amount of torque you need when attaching high in the tree is difficult to calculate. Even though the tree is pitched at perhaps 15° off-center, how much weight are you actually lifting when you pull the tree against the lean? You are practically at the tangent to the arc of the crown's travel downward, and pulling sideways against gravity doesn't take that much force. It certainly isn't equal to the weight of the tree, 'cause you have a lot of leverage.
I suggest that you think about my questions a bit, then adopt a different strategy. Pass the rope over a very sturdy upper part of the tree, probably no higher than 3/4 of the total height. If that is a 2 wheel drive tractor, tie off to the front axle, and pull it in reverse, with positrac locked in. If 4 wheel drive, you might consider pulling in reverse anyway, as it is more important for the operator to watch the tree and chainsaw operator than to see where he is going.

Then put a really good tug on the tree and rope, just to see how it all acts before you need to worry about the tree actually falling. You should be able to gently sway the tree with your rope & tractor prior to ever starting the saw. If it's going to break out the crown, the best time to find out is when no one is standing at the bottom.

Now loosen the load on the rope, and have the operator put just enough tension on it to make the rope "not loose".
Then make a good face cut of about 1/3 diameter, and move around to the back cut. As you make your back cut, watch VERY carefully for the tree to begin settling on the saw. When you detect that the gap is closing, have your tractor operator slowly advance his tension until the tree is no longer settling on the cut. At this point, you are fairly assured of having everything in balance, and you can proceed through the back cut until you think it is safe for the tractor to pull the tree over.

Obviously, this is a risky operation, and depends upon having the experience of knowing how to make the cuts, how to set the rope, and how to pull it with the tractor. But that's how I would do it, and I have pulled a lot of trees over with a tractor.

A last caveat: heavy leaners often fall sideways when pulled over by a tractor. A little breeze, an imbalance in the tree, the feller cuts the hinge too thin... Plop! The damned tree went sideways, because the tractor was going too slow.

Be careful. When your tractor has the tree going his way, that's the wrong time to go slow.
 
Westboastfaller

Westboastfaller

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I thought there was a few great disscutions that a could have added to before I left the thread. May get back to some of them today.

I was meaning to correct my math disaster from the next day after my first post of the thread but didn't get around to it. I apologize to the OP if he was to chech back in. I misinterpreted what he wrote (Did) and then did it wrong myself.
As Timber Fallers, we do the math in our head and average the log measurements to get a rough estimate. Close enough to get a rough volume if the ends are not too different and then just minus 20% for the curvature.
Certainly did not work on a true cone shape. Put me out 50%.

Properly, they would calculate face area on both ends and cone you just half the butt cu ft then times by ' length.
 
Westboastfaller

Westboastfaller

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With a few wedges and a tag on the opposite side it fell where I wanted it too. Beavers been chomping on it for 15 years thats why the base looks like that.
Thought it was a beaver tree. I have seen chicken wire around big cottonwood in the BC interior parts of the Fraser. Cottonwood is not big on the menu in west Canada. They seem to love the Aspen of the interior though.
Looks like a certified beaver though.
Certified beaver goes around the tree and takes out all the live cell sapwood..which is the strongest wood and where barber chairs happen. May be a lesson to us in there somewhere.
They say a lazy beaver has long curly teeth.
A thought a lazy beaver had coarse blonde hair and lives in the bed.

Ok , must be a bad Canadian joke.

Glad the tree went well for you.
Fell a hand full of beaver trees just hanging on a thread.

Instead of a support line you can do a "Jonny hold me right " a channel cut. I use a conventional felling cut then cut out three slim plates each no fatter than chain width then snap the plate with bar by twisting handle up. Make sure the back face is 90° or you are defeating the purpose. This should gives you about 1 1/2 to 2" of vertical face in the back to peel down and hold on much longer.
Sometimes I do it with a bore cut and start with the bore cut first. In small trees you can get away with the 4" bore and 2 flat cuts to match the 2 back corners to complete the channel. You can still aim.. get behind sight lines and put tip against the tree then just imagine top over the distance from sight line to centre of tree.. when the tree is growing straight.
On bigger trees you can just do the bore..2 flat cuts and a modified Swanson out of the front cut (a sharp angle out of the bottom to delay the cut closing and let the butt slip to grownd quicker.)

Lots of wedges. That's good.
Lots of the right wedges and a little hammer will serve you better than a bigger one and 1 fat wedge
 
Brufab
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That's alot of knowledge and experience in that post. I will save it for future reference. Thanks! There's a beaver on our property that has been gnawing on big cottonwood trees along the river edge. He must have messed up teeth he even tried gnawing the bark off a 4" beech. He never took a tree down yet that I could see. I tried to do the beaver a favor and left the top 40-50' of the tree in the bottomland/floodplain for him to snack on. He didn't take any branches but he cleaned quite a few of them bare of bark. I keep the 'how to fell a tree' book by Jeff jepson with me wherever I go just incase I need to double check what I am doing.
 
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