iDRY Vacuum Kilns

Sponsors:

Cutting blown over timber

Started by Celeriac, August 13, 2008, 04:10:31 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Celeriac

What's the proper technique for cutting a tree that's blown over and still attached to the root ball?  The problem I'm running into is that the root ball is trying to pull the tree back up and creating tension on the top side.  The only way is see is to notch the lower side and basically fell it horizontally  ???   If you cut top down it splits.  What's the proper method? 
-Aaron
Currently learning the ins and outs of a Mobile Dimension 128.
"What's that?"
"My sawmill."
"Looks like a VW ran into an antenna tower!"

Gary_C

Blowdown is some of the most difficult cutting I have ever done. And I have the advantage of having a mechanical harvester for cutting and that does not always help.

First thing to remember is when trees with upswept branches hit the ground those branches on the bottom are driven into the ground and are pushing the trunk back towards the stump. So if the tree has been down for any length of time so the root ball has settled into the ground, the trunk has compression forces acting on it as well as the bending forces from laying down. So even if you can cut clear through the trunk at the root ball, you will have your saw pinched from these compression forces, unless the stump falls back into the hole.

The best way to deal with these blowdown trees is to start cutting limbs off from the top of the tree and work your way back towards the stump. Once you get most of the limbs off, mark the trunk with your preferred bucking lengths from the stump to the top. Then start bucking at your marked lengths from the top of the tree to the bottom. And do be careful as you remove logs from the trunk that the tree does not stand upright if the root ball tips back into the hole it left.

The way I cut these blowdown trees with the harvester was similiar. I would move up close along side the tree towards the top and grab the trunk just below a branch or any point where I guessed was a good cutting point. then I would try to lift the tree up and shake it till it was loose and cut the top off. Then I could usually move back down near the stump and cut the tree free of the stump. Sounds easy, but it never was.
Never take life seriously. Nobody gets out alive anyway.

beenthere

And...keep everyone out of the root ball hole when cutting. Not like the guy who didn't know the child was playing in that hole until after the root ball trapped him.  :o :o

All depends on going about it carefully, and figuring out where the tension is and where the tree wants to go.

Sometimes plunge cuts will give you good control while cutting, similar to a leaning tree.

Like Gary_C says, I work the tops over as much as possible. And use equipment and/or cables, winch, and chain to keep safe areas to work.
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

Reddog


Sawyerfortyish

I followed a twister from where it touched down and jumped around through the woods for 5 miles a few years back. Just like your being told cut the top out first.  I did this then I would sort of stand the trunk of the tree up with the skidder my brother would make an undercut then I would lay the trunk back down and he would finish with a top cut. If we didn't stand the tree up he would hit rocks and dirt on the under cut.

Ron Scott

We're working a heavy blowdown area now, but using a FT-153 Fabtek processor. Working on a slope above a creek also makes it quit challenging. We're clearing the main access into the area now.
~Ron

DanG

Quote from: beenthere on August 13, 2008, 06:00:18 PM
And...keep everyone out of the root ball hole when cutting. Not like the guy who didn't know the child was playing in that hole until after the root ball trapped him.  :o :o



What he said!  I'll take it a step further and say you don't want anybody in the way when you're dealing with these.  Disassembling a large blowdown requires concentration, and you can't concentrate on the tree while you're babysitting.  Also, if there is any size to the tree, you shouldn't do this alone, or with inadequate equipment.  It is much safer if your help is experienced too.

I harvested a good sized Longleaf Pine blowdown yesterday, with the help of the landowner and his tractor-loader.  The tree was 18"dbh and about 70' tall(before it fell). ;)  The top was full of heavy branches, and held the bole up a bit, so most of my cuts were a bit higher than I like.  I started by removing all the small branches I could reach, shaking each one to be sure it wasn't bearing any weight.  He removed them with the loader as I cut them, so we kept a clean work area.  Good footing is important, and also it helps to have debris out of the way so you can utilize the best positioning possible, keeping you out of the way of falling branches and out of line with your saw.  Once we got enough weight off of it, he was able to lift what remained of the top, so I could snip off the supporting branches, and he gently laid the log on the ground.  From there it was a simple bucking job.  I got a primo 16' butt log and a pretty nice 12 footer out of the deal, and he got his mess cleaned up safely.  Good deal for both of us! 8) :) :)
"I don't feel like an old man.  I feel like a young man who has something wrong with him."  Dick Cavett
"Beat not thy sword into a plowshare, rather beat the sword of thine enemy into a plowshare."

rebocardo

I do a lot of blow overs, I usually chock the whole trunk with rounds/limbs so it can not roll. What you want to watch out for is the tree barber chairing as it lifts up from reduced weight if you are cutting straight down from the top.

If I am not saving the wood for lumber, I do an big open notch on the underside where it is close to my bar length on trees wider then the bar length about 1/3 through. Then I do stress cuts not too deep on both sides of the notch on the top side. Then I do the cut above the notch towards the top of the tree until it starts to droop just short of the wood cracking and breaking.

Then above the notch at where the hinge would be I do the back cut until the trunk drops to the ground. It helps sometimes to cut an at angle to the trunk base so the top slides under the trunk (it will rip some fiber) and does not trap your saw in the kerf.  I usually stick long branches under the trunk so it does not rest directly on the ground.

Stay on the side of the cut that is attached to the root ball so the trunk you just cut can not roll on you and stay uphill on the final cut.

Do not cut standing on the trunk if you can help it. If you do not do a proper undercut or do not create a mortise and create a barber chair while cutting from the top you can get seriously hurt as the tree lifts and splits.

On trees big enough to require this, I take a cheap metal step ladder with a wide base and cut from that while leaning my arms and body sideways over on the tree. You want to avoid keeping your head, neck, chest over the tree and stand sideways to the tree.

I avoid cutting a big blow 4-5 feet in diameter with a big CC saw at my head level. Just no way to control a kick back that way.

The worse and one of my first blow overs I did, I bought a Husky 365 with a 28" bar just for that tree. It measured 36" diameter on the ground. Once I started cutting the top off and let about 3 tons off it where it was about 20" wide, the tree rose out of the ground about two feet at a 45 degree angle and the 36" tree turned into 54".  It was not one of my happiest moments  :D 

But, at least I was not standing on the tree at the time  ;)

DanG

I had that happen once when I was in the tree! :o :o  I had one foot on the tree and the other on a ladder, about 15 feet off the ground, and I was armed with that ol' Poulan bowsaw I gave Jeff.  The huge branch came off and the tree started back up.  I ditched the saw and hung onto the tree as the ladder fell to the ground.  My Dad was my groundman, but he was laughing too hard to be of much help! :D :D
"I don't feel like an old man.  I feel like a young man who has something wrong with him."  Dick Cavett
"Beat not thy sword into a plowshare, rather beat the sword of thine enemy into a plowshare."

Tom


DanG

He finally recovered enough to get the ladder back up for me. :D  Doing it that way was his idea to start with.  I quit listening to him a long time ago. :D
"I don't feel like an old man.  I feel like a young man who has something wrong with him."  Dick Cavett
"Beat not thy sword into a plowshare, rather beat the sword of thine enemy into a plowshare."

Gary_C

Yah, DanG my father in law did something like that to me once. We had to cut a small Boxelder tree about eight inches in dia that was leaning towards the road. So he had me drive the loader with the bucket up against the tree to push it over as he cut it with the saw. All was well as I had that tree straight up and down when he continued cutting all the way thru the tree and the butt kicked out away from the front of the tractor and the tree started falling right towards my head.  :o :o   

I dove head first right over the wheel of the tractor and rolled away from the tractor. When I got up off the ground he was laughing.    >:(

Plus I had to chase down the tractor that was in low gear and still going.  ::)

He was one of those old school loggers that had learned everything the hard way.  ;D ;D
Never take life seriously. Nobody gets out alive anyway.

Thank You Sponsors!