back cut ?

[murphy4trees]

are we logging or falling a spar in the backyard?

I think that there is a huge difference between the two and we need to be aware of this in having this discussion. There are some cross-over techniques, and there are a lot of differences to be considered. When it's suburban arboriculture, then precision falling is the objective, and I will almost always be using a pull line with plenty of force. Rarely use wedges..

SO the following thoughts are about falling trees in peoples yards, not the woods.

It can be extremely difficult to pull the tree over when the backcut is made even a little below the face, so the main reason to cut the backcut slightly above the face (which I do not recommend) is to make sure that it is not cut below the face. Also having the tree kick back is very rarely a concern, cause we are not falling in the woods or up a hill etc.. And with an open face cut, which is almost always recommended in cases where logs are not getting sold, and no obstructions, needing to stop the tree from kicking back off the stump is rarely a concern.

SO cutting the backcut level with the face allows for more precision in directional falling. The grain can get funny and twist between the two levels when cutting a high backcut, which can cause hinge failure. And it is easier to misjudge the hinge thickness when cutting a high backcut and thereby overcut the backcut again resulting in hinge failure. (what casues the misjudgment is thinking the wood between the backcut and the roof cut of the face, level with the backcut, is holding wood, when really the only holding wood is the wood from the apex of the face back to the backcut)

Cutting the backcut high adds nothing to the precision and can actually casue catastrophic failure so again the only reaon to cut slightly high is just to make certain you are not cutting too low... Unless you are in the woods...

 

[lxt]

this is just the way the pros taught me when i was being taught how to top trees and what not.

Surely none of the pro`s at bartlett taught you to "TOP" Trees?


LXT..............

 

[moray]

One of the reasons to cut slightly above the apex of the notch is to increase the angle of the arc in the hinge making the hinge more flexible and better able to do it's job. To explain this a little better with exaggeration, it would be easier to break a stick over a 1" pipe than it would be to break the same stick over a 55 gallon drum.

This is an excellent point. There is a lot of difference between a hinge no thicker than a saw kerf and one that is an inch or two high. Since the butt of the tree is always pushing backward as the tree falls forward, a late-breaking hinge offers better control and delays the moment when the backward push can actually do something bad.

 

[LTREES]

I AGREE, HAVE NOT USED MY INSURANCE YET, HOPE NEVER TO DO SO.:greenchainsaw: :greenchainsaw: :greenchainsaw:

 

[Wortown Mick]

Surely none of the pro`s at bartlett taught you to "TOP" Trees?


LXT..............

Hey hey now.. The bartlett boys are eckspurts not pros... hah

Ill never understand all you folks who try to profess wedges.
Theyre junk for directional control IMO.. great for stopping the kerf from closing but not to be used as a tool for guiding a tree.
Thats what a taglines for.

Huge difference between PNW felling and general tree work.


Id rather not get into my methods but I tend to use an open face cut with a sloping backcut. Not a radical slope but nowhere near as flat as reccomended.
Id say I probably start the backcut like an inch higher for every additional 6" of tree diameter.

IE 24" tree = backcut starting 3-4 inches higher than it ends up as it reaches the hinge. Makes me feel safer from kickback. Is it any safer? probably not.


Every tree is different though as mentioned before. If theres a risk for a barbers chair with a leaning, stressed, or rotted tree a different approach would probably be taken from the beggining.

 

[Husky137]

Why am I not surprised.

 

[clearance]

I think that there is a huge difference between the two and we need to be aware of this in having this discussion. There are some cross-over techniques, and there are a lot of differences to be considered. When it's suburban arboriculture, then precision falling is the objective, and I will almost always be using a pull line with plenty of force. Rarely use wedges..

SO the following thoughts are about falling trees in peoples yards, not the woods.

It can be extremely difficult to pull the tree over when the backcut is made even a little below the face, so the main reason to cut the backcut slightly above the face (which I do not recommend) is to make sure that it is not cut below the face. Also having the tree kick back is very rarely a concern, cause we are not falling in the woods or up a hill etc.. And with an open face cut, which is almost always recommended in cases where logs are not getting sold, and no obstructions, needing to stop the tree from kicking back off the stump is rarely a concern.

SO cutting the backcut level with the face allows for more precision in directional falling. The grain can get funny and twist between the two levels when cutting a high backcut, which can cause hinge failure. And it is easier to misjudge the hinge thickness when cutting a high backcut and thereby overcut the backcut again resulting in hinge failure. (what casues the misjudgment is thinking the wood between the backcut and the roof cut of the face, level with the backcut, is holding wood, when really the only holding wood is the wood from the apex of the face back to the backcut)

Cutting the backcut high adds nothing to the precision and can actually casue catastrophic failure so again the only reaon to cut slightly high is just to make certain you are not cutting too low... Unless you are in the woods...

I disagree, strongly, when in Rome, do as the Romans. When falling trees, buttlogs, whatever, act as a faller. I have been very fortunate to have had a few Westcoast fallers teach me some key things. The rules for falling here, British Columbia, are the best, some of the biggest wood, some of the nastiest ground in the world is here. Thousands of years of combined skill have helped make these rules. Many, many deaths, thousands more very close calls were the impetus.
A little tree can kill you just as dead as a big one Daniel.

Show some respect, educate yourselves, others have gone before and figured it out, take advantage of that and be safe.

 

[techdave]

Those who discount wedging probably dont understand it...

Howdy all, those of us who customarily use wedges are generally not trying to steer a tree with a wedge.

The hinge and its associated modifications are pretty much how we direct trees. Sometimes a wedge may be useful to modify a leaner's behavior until its vertical enough or forward enough for the hinge to take over.

Besides all the good things and safety reminders, a couple of things people have said here jumped out at me.


One is a concern that a backcut higher than the face apex would somehow make for a different hinge characteristic than a backcut even with the apex.

As the fall progresses at some point that would be a true observation, but for initial deflections in most wood, the angle needed to transfer enough weight to the face direction is small, probably 10 degrees or less. For moderate to large trees of say 18 or 24 inches and up, the wedged backcut is just a way to trnsfer weight to the falling direction. That is why so many of the PNW style vids on Youtube end with the faller wedging.

Always sawing up to the point the tree commits might indicate a need to fine tune hinge placement and techniques??????

Also I wonder if its really true that "city" tree work is really aimed more accurately than production felling in the wildlands??.

Even scrubbies like me usually are accurate to about 1-2 foot per 50 feet of height if we have to be and are given the time to plan hinge corners carefully via rope or sighting sticks.

Crossing the lay, f-ing up the strip layout, and busting up thousands of bucks of bole aint like crushing the roof on a pro-athletes mansion, but still costs enough nobody is lacksadaisical about their aiming either? I aint PNW logger bu tI am guessing guys pride themselves onhititng their aiming points as needed??

To be sure, I realize one or more ropes can PREVENT a tree from going where its not supposed to, but I doubt any of your methods can SAFELY pull (like no fast vehicle driving) a moderate to large tree as fast as it falls, in a direction FAR from where the hinge is aimed.

I reckon "you all" are aiming with the hinge just like "us' from the wildlands, you re just preventing bad directions and sometimes partially guiding the fall with your ropes.

just my two cents, thanks dave.

ps__Dont forget BUCKING, an art and science that can be just as nasty as falling, and is done more often!!

Combined sidebind and endbind on a 3 footer on a 30 degree slope anyone?? ha ha

 

[randyg]

Generally speaking, the distance (measured in degrees) between the undercut and the bottom cut (top and bottom of the face cut) determines the precise moment that the hinge will fail and the butt will no longer be connected to the stump. Sometimes we 'open up' that face cut greater than 90 degrees and the hinge never does fail, so the butt doesn't fall on a sidewalk for example. Ideally that hinge will 'bend only' until the face cut closes completely, but we all know that just is not always the case. When wood is frozen or dead or crown brushes another tree as it starts to tip (or other perhaps unforseen reasons) and the hinge fails prematurely, then having made that back cut above the apex of the face will create that vertical ledge on the back side of the hinge wood and gravity will cause that butt to drop slightly and stay trapped behind that ledge to provide time (additional margin of safety) to escape. Without that ledge the butt might slip and drop down on the back side of the stump. Wish I could say "I never saw that happen", but glad to be able to say, "thank God it missed my foot".

randy

 

[murphy4trees]

exactly what I AM talking about

Clearance... your mentality is exactly what I AM talking about..

You think that falling a spar or tree on level ground in a backyard with no overhead hazards requires the same skills and techniques as falling a tree in the PNW... It aint so and to say that suburban arborists need to fall the same way loggers do is a mistake...
I honestly have never worked with a logging or even a landclearing operation... That is another point... even land clearing is a different game than logging.... back to the subject....

From what I have read and heard, it is clear to me that the good loggers have a lot of tricks up their sleeves and can pull off stuff with a good saw that would amaze even the most expereinced suburban arborist.... Yet that does not mean that we should cut trees the same way they do in all situations..

Here are the main differences....
#1) How you get paid....
Loggers get paid for the wood and therefore they make cuts that will reduce the damage to the value of the log.... Getting paid for the wood is just about the last thing I think of when falling a tree... My concern is getting the tree on the ground safely, doing no damage to property and as little damage to turf as possible.... Now that right there is going to make a huge difference in how the cuts are made

#2) an arborist has a different set of available tools than a logger.. A logger just can't carry around all the gear in my truck through the woods all day... I might have 2 or three throw lines, several different pull lines, blocks and slings for redirects, rope come-along, lowering T on a big shackle on the pindle hitch of a 4x4 pick-up with auto trans in 4-low on blacktop, the GRCS, several saws with bars from 16-36", Spikes, saddle, lanyard, rope guide...etc I have so many more options than the logger... I can set a pull line and a retainer line, or maybe two seperate pull lines on a heavy back leaner, I can take weight off, take the top out, or cut it 15' high from the spikes etc... I can strap or chain up a potential barber chair, or tie two leads of a co-dominant stem together etc...
Now what does a logger have... 1 saw, a hammer and a few wedges.. (I've got wedges too, but rarely use them) Now that is going to make a huge difference in how the tree is cut... He is forced to do things with his saw and wedges that I would never have to do... That is a much different game..

3) Risks... When a tree goes the wrong way for a logger he may have screwed up his lay and trashed some very valuable logs.. SO what... does he really sweat it? (I don't know), does he lose his job or ruin his reputation, does he have to pay for the damage out of pocket, or risk losing his insurance and maybe even his business? Will his job get shut down, or his equipmnent damaged.. though I suppose the logger could kill someone with a lost tree, if the 2x height rule isn;t followed, but in general the logger risks far less when falling a tree than the arborist... The logger can make the cut if he is 90-95% sure he can make the drop... Whereas the arborist may be 99% sure, but still have to call the crane, because he can;t risk the 1% chance of catastrophic damage... Now that is going to make a difference in how the cuts are made

4) visibilty... It is very rare that arborist has obstructed visiblity. Not so for the logger... This is going to affect judging the lay etc.. And safety in spotting overhead hazards.

5) grade... especially in the PNW.. the logger may have to deal with falling on steep grades, where in my local area, flat ground is the norn though we occasionally deal with moderate to medium grades..

6) SAFETY... in general th arbosrist does not have to deal with the following risks:
cutting dead snags that could fall with the next gust of wind...
overhead hazards like killer hangers that can break free from the vibration of the saw
throwback from contact with other trees during the drop..
the risk that another nearby tree will fall from the vibration of the fall..
ETC...
The point is that there is a lot more ways to get killed falling trees in the woods than in backyards... Escape time is a crucial life saving factor in the woods. It rarely is an issue in the backyard...

7) Time/repetition... An arborsit can work all week.. and never cut a notch. He might exclusively prune and cable, or have the crane pic every cut.... I felled 8 or 9 trees today... most of them under 8" and none more than 18" Chipped it all... Now how many trees does a logger fall in a day... I may have spent under 5 minutes today actually falling trees... Can a logger say the same? He has to be faster and more efficient than me when falling because he does it over and over all day, every day... If he spent an extra 30-45 seconds on every face that would cut his productivity.... I on the other hand can take 10 or more extra minutes to carefully face a tree and do whatever I do with the backcut to save hours of climbing and rigging... I have the time to set pull lines etc.. He doesn't... Now that is going to effect how the cuts are made

That is all I can think of right now... AND that is enough to make the point... Logging is a different game than falling trees in residential neighborhoods... MOST OF THE TIME... Arborists have a lot to learn from loggers no doubt... BUT to think that we need to cut trees the way they do is a big mistake..

Sorry for the rambling... I think this is a very important point though, that our industry has yet to realize...

 

[randyg]

Clearance... your mentality is exactly what I AM talking about..


I honestly have never worked with a logging or even a landclearing operation... That is another point... even land clearing is a different game than logging.... back to the subject....

From what I have read and heard, it is clear to me that the good loggers have a lot of tricks up their sleeves and can pull off stuff with a good saw that would amaze even the most expereinced suburban arborist....

Sorry for the rambling... ..

Thank you for your HONESTY Daniel. Having NEVER DONE, but only READ AND HEARD certainly explains IMO why you've protested so much.
And the subject was???? Oh yea, WHY we place that back cut above the apex of the face cut. It creates an extra margin of safety, thats why. I attempted to explain in a previous post. I'm with Clearance on this one Daniel. Ignore the warnings passed down and someday, someone will pay a price for that ignorance.

 

[Marty B]

Snipe it

We put our back cut in about 1" to 11/2" above the level cut on the pie....If there is a chance that the top of the tree should fall against a near by tree or when falling up hill, we snipe the stump. This creates a "Humbolt effect" that allows the falling tree to slide down the stump thus help prevent "Barber Chair" or throw back. Thats how I was taught and it has worked for me so far.

 

[mattfr12]

Surely none of the pro`s at bartlett taught you to "TOP" Trees?


LXT..............

nope i only top the if im doing a removal. none of the guys thier showed me this i picked it up years back from an old timer that could drop branches out of a tree on a needle. i wouldnt recommend it. ive just done it a few thousand times and kinda perfected it. you have to have a light trigger finger because if you take to much you will loose your hinge to soon before the the top is headed in the right direction.

 

[Scots Climber]

Humboldt undercut guys, with the backcut level and a little above, always. If you are worried about it coming back, which can happen sometimes (like if it hits another tree), this is the best way. The conventional notch is not as good (also wastes wood in a money log) for this, the raised backcut is the only thing preventing it from coming back. Not os with the Humboldt, when she goes over, she is gone.

When it starts to fall you should move quickly away on one of your two escape paths, looking up and out for falling debris. Remember, full, sharp saw, three wedges min. and put your facescreen down.

Aye, been there, ok, only with relatively small Sitka's in Scotland but having had an 60m, 3 ton lump of timber jump off the stump at me, I can only say that is sound advice.

 

[Scots Climber]

nope i only top the if im doing a removal. none of the guys thier showed me this i picked it up years back from an old timer that could drop branches out of a tree on a needle. i wouldnt recommend it. ive just done it a few thousand times and kinda perfected it. you have to have a light trigger finger because if you take to much you will loose your hinge to soon before the the top is headed in the right direction.

Perfected, no. Practiced, yes. You learn something new every time you climb or fell a tree. Trees are living things, ergo unique.

 

[mattmann1972]

2" of holding wood for every ft of diameter over 5 ft @ DBH

Thats my golden rule.

 

[cmetalbend]

Backcuts

I'd like to chime in on Backcuts. One practice I didn't hear discussed was directional felling. I have used a method for years that goes somthing like this. Using the traditional face cuts, I proceed to the back Depending on the size of the tree and wind I move up 6 inches to as much as 2 feet above the face cut them cut down diagonally toward the dept of the face cut. 45 degree's or so. What I found is if the tree is headed down the wrong path it'll pinch before it's too late. If the gap of the cut opens it'll go the right direction. A pinched saw means you need ropes and pressure. Once enough pressure is applied the saw will free and you can proceed. This may not be the right method. But when dealing with straight woods, it can be very difficult almost impossible to tell fall direction. I use this alot when dropping trees next to buildings. Before sombody says it, I know tie the ropes first. I'll post a picture, for better clarifaction.

 

[cmetalbend]

pic.

Here this may better explain.

 

[Sprig]

Here this may better explain.

Hm, "WordPad has caused internal error in kernal blah blah blah", could someone put that link into a more readable format please?

Thanks,

Serge

(Cmetalbend, do post pics, I think what you described is a sloping backcut and is potentially very dangerous (ie. the back part of the stump splitting, barberchairing etc.), I don't think this can be refered to as 'directional falling' but rather bad technique, my opinion)

 

[randyg]

I'd like to chime in on Backcuts. One practice I didn't hear discussed was directional felling. I have used a method for years that goes somthing like this. Using the traditional face cuts, I proceed to the back Depending on the size of the tree and wind I move up 6 inches to as much as 2 feet above the face cut them cut down diagonally toward the dept of the face cut. 45 degree's or so. What I found is if the tree is headed down the wrong path it'll pinch before it's too late. .

I see stumps with this 45 degree back cut signature often and it makes me crazy! Making a lot of extra saw dust in vain. The few times I have caught and asked why, the reply was either "thats how I was taught" or something about a higher kick plate or so the saw doesnt get pinched as bad if she tries to lean the wrong way or so it won't barber on me.

If the butt barbers, it will blow that little ledge right off the back side of the stump when it does, thats not gonna stop it. Use a humbolt face and run that back cut a bit above the apex of the face and thats all the kick plate you will need. Stick a wedge in BEFORE you get pinched and you never will get pinched again. Did I say never? (Should never get pinched again) Level back cut though, or slight incline only, none of that 45 degree crap. Much easier driving a wedge if you can swing like a pendulum rather than swinging up and down if you need to move that tip in the right direction.

HINT: Carry a spare bar nut in your cuttin pants pocket with a piece of string about a foot long tied to it. Especially on a side hill, you can take that little 'plumb bob' out of your pocket and hold it at arms length up high and sight past the string at the stem of the tree from a couple different sides of the tree and know exactly which way it is leaning. Takes the guess work out of which way the tree "wants" to go. Don't ignore that breeze.

Anticipating barber chair activity and preventative measures should perhaps be another thread?


randy