Top Down Vs Bottom Up Removals

[defensiblespace]

I recently read an article in the August 2012 Arborist News about the differences between top down and bottom up removals. The conclusion of the article was that the branches on a tree dampen the vibration through the trunk, reducing the risk of failure in trees that have structural defects. I decided to put this idea of top down removals to use, and in the meantime, became more proficient at it and found other uses for top down as well.
This week I removed a lodgepole pine that had a squirrel nest in it about halfway up. This is a pretty good indication that there is some advanced decay in the tree. The tree also had a slight lean towards the house it was up against. I decided on a top down removal for 2 reasons. The first being that there was decay in the tree and climbing past it would put me at risk. Having the branches on the tree would help reduce the vibration in the tree, therefore reducing its risk of failure. The second reason was that with the tree being up against the house, I would not have to rig and lower the branches that were growing over the structure. I climbed up the tree leap frogging the branches using a 2 in 1 lanyard. I had to go fairly high in the tree due to a small drop zone. I tied a bull line to the top, lowered a few feet, and had my groundies pull as I was finishing the back cut. The top came out and landed where I wanted and the vibration in the tree was minimal. View attachment 301420
Attached is a picture of the aforementioned tree after my groundie made the bottom cut. You can see the decay.
I will definitely be doing top down removals when the situation applies from now on. Anybody else out there doing these in trees with defects or to eliminate the need to rig and lower branches?

 

[imagineero]

I'm not sure I'm making sense of what you're saying here.... the only practical way I can see of doing a top down removal is with a crane, otherwise how are the branches going to get to the ground? Everything would hang up on the way down, especially if you're rigging.

 

[beastmaster]

I didn't know what it was called, and I never gave much thought to it reducing the wobble of the tree(Understand the concept)But Ive many times have climbed a conifer and taken it down piece by piece with the limbs intact to lessen the chance of damaging something below by dropping limbs.
I recently did a leaner over a house with a steep roof. I was told I would have to lower all the branches with a tag line. After seeing the tree in person I took half of it limbs and all, then pulled over what was left. I pull up a rope bag when I get to the top, tie the rope, then toss the bag out to the ground. Some times I might remove a limb or two so I'll be in the clear or to make sure it won't hang up where Im making my cut. On rare occasion I have climb to the top of a tree and started limbing on my way down, This was so the lower limbs world protect something below, this can cause a bird nest of branches, and the release of a lot of weight at one time if a bunch of limbs go at same time Your surely not going to lower any limbs like that.

 

[rtsims]

Beast that sounds much more efficient than rigging it limb by limb. Obviously the scenario is not always ideal to do this. My question is have you used this technique and rigged the tree down and not just pulled the pieces over? In my mind I see a tangled, hung up mess while lowering the work.

 

[Zale]

Its a safer way but it can also result in more time. I've found you don't have to leave all the branches below you to dampen the shock load. Leaving a selected few can give the same result while allowing for easy flow rigging. IMO.

 

[StrataTree]

I've heard in Europe they do a lot of top down removals, anyone else hear this?

 

[Pelorus]

I've climbed and dismantled hordes of decrepit trees over the years, and vibration dampening seems like a crock to me. If the tree is severely grim, I use some ratchet straps to help maintain structural integrity, or "fishing pole" it using a couple of extra blocks. (Antal / "X" rigging rings in a spliced eye sling are light, strong, and cheaper than blocks). All I know is I'm gonna put that tree on the ground as safely and efficiently as possible, and trying to lower upper limbs through lower limbs causes drama and increased mental / physical stress.

 

[miko0618]

I posted a similar thread on 3 norway spruce removals. one was spike up, remove as you go. one was climb up, set line, rappel and work your way up. and the last was climb up, top and work your way down. all were not rigged. my favorite way is to climb it, top it, set a friction saver and go back down to work the tree. topping it intact is more stable but dropping limbs onto themselves sucks. it makes a giant mess. it preloads the attached limbs to the point where you have no control. I have dropped upper limbs onto lower limbs in hardwood trees and let me tell you, when the upper limb hits and usually breaks the lower limb it sends a good shock through the stem. as far as rigging, if you think it might break the stem, don't do it. if your on a clean stem send small pieces down. if i know ahead of time that rigging isn't really and option, i tell the homeowner what damage to expect. which is usually a pretty dented yard.

 

[beastmaster]

Though I have also one or twice over the years caught a top after climbing up limbs and all, It seems if you even leave a stub while limbing your way up, something will catch on it. even leaving a few branches to dampen the tree will more then likely get something hung up or kick out branches where you don't want them. I have always for the most part started limbing from the bottom working my way up on removals. On trims I normally start from the top and work my way down. On some trees no limbs will make it to the ground for a long time getting hung up tell their pulled or cut down, then a bunch may fall all at once. Ground guy will be standing around doing nothing for a while then have to work their asses off. Thats on a trim, it would be worse on a removal. Plus unless your taking chunks also you'ed have to climb back up it. seems like a lot of unnecessary climbing. That is on single trunk conifers, decurrent tree might be different.
Doesn't make since unless I'm missing something. That doesn't include taking limbs and all in some situations. The right situation it can be a real time saver, making it so you don't have to lower down a bunch of limbs.
There are always exceptions but as a rule I say bottom up tell some one shows me different

 

[defensiblespace]

I've climbed and dismantled hordes of decrepit trees over the years, and vibration dampening seems like a crock to me. If the tree is severely grim, I use some ratchet straps to help maintain structural integrity, or "fishing pole" it using a couple of extra blocks. (Antal / "X" rigging rings in a spliced eye sling are light, strong, and cheaper than blocks). All I know is I'm gonna put that tree on the ground as safely and efficiently as possible, and trying to lower upper limbs through lower limbs causes drama and increased mental / physical stress.

Pelorus,
The vibration dampening of leaving the branches on is not a "crock". Its actually been studied and proven. The fishing pole technique is not something that I have seen or heard of until now. I'm picturing it in my head though, and I assume its a way to keep any section of the tree above a potential failure from hitting the ground with you in it? Seems like a cool concept. I would love to see it in person. I should have pointed out that top down removals are more applicable to excurrent conifers. I have only done a couple trees this way so far, but I have yet to have any hang ups.

 

[defensiblespace]

Clarifications

I think I may have confused people on this one, so a couple of clarifications. I only do top down removals on single leader (excurrent) conifers. The idea is to climb all the way to the top of the tree, while only removing branches that may be in the way of your ascent. I find these are usually smaller branches that I can cut and throw far enough out from the tree that they don't get hung up. Once at the top, set a running bowline and throw the line out from the tree in the direction you want to drop the piece. Rappel from the line to where you want to make the top cut. At this point, you may want to remove a few branches to make room for your face and back cut. I like to make a shallow face cut in order to get the top to jump out away from the tree. From here I just repeat the process. I have only done a few removals this way so far, and would not do a top down removal unless the situation calls for it. I would also not rig and lower anything with this technique. That would obviously defeat the purpose of doing a top down removal since one of the objectives is to avoid having to lower branches. I hope this clarifies things. I just wanted to see if anyone else out there was doing this and maybe pick up some new ideas along the way.

 

[Pelorus]

Pelorus,
The vibration dampening of leaving the branches on is not a "crock". Its actually been studied and proven. The fishing pole technique is not something that I have seen or heard of until now. I'm picturing it in my head though, and I assume its a way to keep any section of the tree above a potential failure from hitting the ground with you in it? Seems like a cool concept. I would love to see it in person. I should have pointed out that top down removals are more applicable to excurrent conifers. I have only done a couple trees this way so far, but I have yet to have any hang ups.

It's a crock to me. :msp_rolleyes:
I'm just not buying into vibration dampening as a practical or even safe work method. If the tree is really that precarious, (to actually require leaving lower limbs on in order to dismantle it from the top down), then climbing it in order to do so is patently unsafe.

 

[RAG66]

I'd love to see this done on the 130' Douglas Fir I did about 3 weeks back. I'm not squashing the idea but I can't see anything but a mess. The only way, or the way I know to work best, is bottom up. I usually work a group of limbs together with web slings attached to carabiner. This gives all the control I need. I have never thought of shock remediation as a factor, although understood, it usually isn't what I am thinking about. If the case came when a zip line to transfer brush out to the street over the yard then I could see doing a top down, why climb it twice. This would be like a crane without the crane only smaller pieces.

 

[Iustinian]

Pelorus,
The vibration dampening of leaving the branches on is not a "crock". Its actually been studied and proven. The fishing pole technique is not something that I have seen or heard of until now. I'm picturing it in my head though, and I assume its a way to keep any section of the tree above a potential failure from hitting the ground with you in it? Seems like a cool concept. I would love to see it in person. I should have pointed out that top down removals are more applicable to excurrent conifers. I have only done a couple trees this way so far, but I have yet to have any hang ups.

Fishing pole method is simple: set a series of sling/block combos up as you ascend. It is a variation of butt-hitching, like when you are blocking down big logs, but instead of having to move your sling and block, you have several of them already set up before you send the first piece down, with the rope running through the entire series of blocks the entire time. It is "gear-intensive", meaning that it takes a lot of slings and blocks to build the system, but it does have the advantage of spreading the impact generated by the dynamic load across several points (or even the whole) system.

I also think that if the dampening effect is that crucial of a factor, then there are much better ways to mitigate the risk then depending on the remaining limbs to reduce the vibration. If in fact it has been studied and proven, has the data been extrapolated and broken down to a usable factor to the extent that you can use it to make accurate calculations of the work you are about to do, or are you just guessing/hoping/praying/grasping at straws? For instance, it has been studied and proven that material is more dense in cold air than hot air, but has the notion that performing removals of trees with questionable safety factors such as rot or decay in cold weather would be safer than removing them in hot weather simply because their mass may be collected more densely during cold weather? hmmm.

 

[gorman]

I sometimes leave lower branches on a trunk when I'm doing a removal to dampen any rigging forces. But only if they won't get in the way. It's tough, but if you can leave them, it's only going to help.

 

[chief116]

I don't get it. You have plenty of room to blow the top off a large single leader (excurrent) conifer, but you are going to climb past branches with a chainsaw attached to you, in order to get to do the top first? If going swinging in the breeze isn't your thing, maybe just keep climbing a little higher and take a smaller top? Train a guy to run a rope? How does this method time out from a production standpoint? do you have ground guys staring at you, chasing twigs and pine cones for a few hours, then you bury them with the top and all the logs still covered in brush?

 

[StrataTree]

Pelorus,
The vibration dampening of leaving the branches on is not a "crock". Its actually been studied and proven. The fishing pole technique is not something that I have seen or heard of until now. I'm picturing it in my head though, and I assume its a way to keep any section of the tree above a potential failure from hitting the ground with you in it? Seems like a cool concept. I would love to see it in person. I should have pointed out that top down removals are more applicable to excurrent conifers. I have only done a couple trees this way so far, but I have yet to have any hang ups.

"Studied and proven". Just like global warming and most of ya aren't buyin that.

It actually makes sense to me, but if I need to climb a tree that way cause its too sketchy, then I shouldn't be in the tree!

Anyone ever cut a top out with branches below and had it hang up? Just curious.

 

[Blakesmaster]

I don't get it. You have plenty of room to blow the top off a large single leader (excurrent) conifer, but you are going to climb past branches with a chainsaw attached to you, in order to get to do the top first? If going swinging in the breeze isn't your thing, maybe just keep climbing a little higher and take a smaller top? Train a guy to run a rope? How does this method time out from a production standpoint? do you have ground guys staring at you, chasing twigs and pine cones for a few hours, then you bury them with the top and all the logs still covered in brush?

I use this method when there is something directly under one side of the tree but an open dz on the other. Easier than roping the half over the fence/shed/etc.

 

[Pelorus]

If you feel a top down removal makes a dicey situation safer, then go for it. Worrying whether a tree is gonna fail with climber in it ain't good for the mental equilibrium. I'll sometimes install a tensioned guy rope in a sketchy leaner just for some added peace of mind. Or, fishing-pole it, or digest it in smaller bites, or all of the above. The top-down removal method (for vibration dampening) is just a technique that ain't gonna end up in my recipe book. My fossilizing bones don't like chasing hung up limbs and re-climbing a removal tree for additional exercise.

 

[rtsims]

I will most defiantly use this technique in the future. That being said I won't be using it because of the "safety" benefits, but rather for the purposes that Beast mentioned. It makes perfect sence to me, what you lose in time weaving through the limbs on your way to the top, you gain by not rigging all those limbs on that side of the tree.