Root ball torque

[ArtB]

Need to pull over a 4 ft DBH, 150 tall black cottonwood in the back yard, it is starting to drop widow makers and grandkids play there sometimes in the summer. Told them if they ever hear up above what sounds like arrows going into a hay bale, run like heck!!!!

Center of Gravity (which is about 70 ft up) has a 4ft offset toward the house 100 ft away or I'd just fell it.

Have JD440 and Ford 4500 hoe and a 15,000 winch and big (old 6 ft dia DFir stumps) to tie into.
Have pulled over 3 ft dia DFir with about 250,000 ft# of net torque on the root ball, and have felled this big of B. cottonwood before but never pulled one this big out by the root ball before. Suspect more difficult to pull than the 3 ft DHB DFIr?

Also figure I have over 150,000 ft-# of torque to overcome for the lean, then need to get high enough to pull out the root ball.

Anyone have a good estimate of the torque needed???
Good solid base, this thing withstood the columbus day and the inauguration day (100 mph) winds without falling, so pretty solid. Got lots of 5/8 wire rope and blocks, so getting the leverage and force is no problem, just dont want to rig up more than I need. Good fork 70 ft up to tie into with the wire rope.

 

[ASD]

I would be REAL careful with trying to pull a cottonwood over they are no were near as strong as a fir they are very brittle with the type of force you are going to need to pull it over root ball and all the tree will snap way before the root ball comes up.

 

[056kid]

I would face & back the tree, THEN pull it over...

 

[treemandan]

Torque?

 

[dancan]

Not the kind of torque I was thinking about in regards to the ....

 

[2dogs]

Pulling over a tree can be a good idea at times but each tree is different. You want to use the minimum amount of force necessary to do the job safely. ALL your rigging most match the job and the maximum force applied to the line

I don't know what you mean by the available torque you have. Torque is twisting force that can be measured on a dynamometer. You have a finite amount of line pull in a straight line (with no mechanical advantage i.e. moving blocks). You also can manipulate the leverage by moving the point where the tree is attached to the wire rope by moving up the tree. The tree also has its own limits, that is the farther up the tree you go then the weaker the tree is. In addition each crotch weakens the tree even more.

For most all conifers 30-50 feet up the tree is adequate to steer the tree. By steering I mean the tree is still notched and backcut, the rigging pulls the tree into a lay it was not going to hit. The notch and backcut are modified, usually smaller, to suit the tree. If you guess wrong and leave a thin hinge that breaks then the tree can go anywhere. If you leave a thick hinge that breaks the rigging (happened to me) then the tree will likely go over backwards.

If you can climb the tree to place the rigging then you can also climb it to reduce limb weight from the backside.

 

[380LGR]

I would scratch at the stump on the back side with the hoe and pull it over with the skidder. I think you are way over thinking this.

 

[hammerlogging]

I would scratch at the stump on the back side with the hoe and pull it over with the skidder. I think you are way over thinking this.

Or notch, backcut, pull tree over, then dig out root wad or just grind it, or cut it flat and stick a potted plant on it.

 

[380LGR]

I agree didnt think he might be smart enough becuase he wanted to pull the hole thing over.

 

[ArtB]

Thought someone may know a reference work that actually has pulling torque (pull times height) needed for different species and sizes. Or even a reference work with probably wind speeds and seasons that will fell various tree species and sizes. Did not find anything on a quick net search.

Already have dropped 2 BC in the yard that were bigger (one measured out at 168 ft tall), with cable rigging and 36" saw. ref previous post, -- 42", 148 ft BCottonwood over top of house , April 2, 2004 post.

Posted this query as am curious about the force needed to upend a cottonwood root ball as a couple in nearby yards in recent years have blown down across the main road, luckily not killing anyone.

Thanks for the breakage possibility reminder, was 'unfortunately' aware of that possibility (learned that the hard way with dozer and alder, spent 2 week in hospital in '74)

 

[lego1970]

I don't know the answer at all but, if you pull the whole tree over root ball and all, it might help to let a sprinkler run overnight on the back side of the tree to soften the soil up. Other then that I have absolutely no suggestion. Good luck.

 

[fmaglin]

I would face & back the tree, THEN pull it over...

That's how I'd handle it.....

 

[Hddnis]

There might be some reference tables that would give you the strength of the green wood; it might be for making pallets or cribbing.

Only reason I could think of to take measurments of forces to pull a tree over would be for rigging purposes when working with a yarder. I've never known them to use cottonwood for that.

I recently removed a few cottonwillows (I believe the same tree, different local name) and they will surprise you with how strong they are and with how they break unpredictably. The neighbor tried to pull one with his big JD tractor and it split the trunk before the roots gave way. A couple days later I dropped on half of a forked trunk on one of my trees and the remaining trunk and tree fell over. The roots were rotten and the tree was just sitting there balanced.


Mr. HE

 

[Humptulips]

I will tell you this. I don't know beans about torque but from my years picking stumps for guylines and tailholds a cottonwood is very well rooted and I would say you are biting off a lot if you plan to uproot a 4 foot cottonwood. They have a very deep taproot and I think digging around the stump may not help you much.

 

[dingeryote]

I will tell you this. I don't know beans about torque but from my years picking stumps for guylines and tailholds a cottonwood is very well rooted and I would say you are biting off a lot if you plan to uproot a 4 foot cottonwood. They have a very deep taproot and I think digging around the stump may not help you much.

LOL!!
Yep! Around here it's sand. Lots of busted up Cottonwoods after storms, but ya never see one that's gone over.

I'm voting with 056 on this one. Face it, and fold it with the cable, then dig things up.

Pulling it over could easily result in busted limbs slingshot onto the house.

Stay safe!
Dingeryote