1/3 Diameter Notch Rule

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im of the understanding that 1/3 to 1/4 is all that is normaly required, howver on a back leaning tree, or a tree that has lost its crown a a scarf of 1/4 to 1/2 is a good practice to adjust for the lean or loss of crown weight.

i ALWAYS use wedges, to direct the fall, also a correct amount of hinge wood ( Approx 1/10th of tree diameter) variable each side depending on the lean.

when it requires you to pull the tree down a, simple 4 to 1 rigging set up, with prussiks works very well, and im a fan of this, 10 min to set up = professional and controlled fell.

however im always keen to hear if im useng bad practices, and open to any suggestions

thanks.


'You have to touch and tree, and feel it" Shigo
 
And of course, weight isn't everything. Traction plays a big part, proportionally speaking, depending on the angle of the line tying it to the tree. Of course, weight also comes into play in determining traction, and they're all kind of inter-related.

I was fairly amazed with what we could pull over with our Massey Ferguson 85 (~62 hp, 8000 lb tractor with tires loaded). The gearing and torque of the engine, combined with the foot print and tread depth of the ag tires on the rear wheels, and it does a number on the small trees we've pulled with it... one actually I jumped the gun on, a ~1.5 ft dbh spruce and ended up with a 2 inch hinge. Probably didn't even need much of a relief cut and the tractor could've just pulled the tree over on it's own...

That is the problem with pulling with a tractor or truck not steady
and easily wrong timing. The winch is steady and with two speeds
and faster if you gas it, it is awesome and I trust it over any groundy.
 
My set up you would have to see in action to see its performance!
A pto winch is the best tool a man can get. I will start by putting
it up twenty foot and freespooling to back to a safe distance and
set air brakes on my bucket. Next I engage winch usually in low
to reel in access line and then kill the truck pto in gear. I then
cut notch and make kerfs and stop saw. Now I get in bucket
start in gear and tighten until I see a little shake or the top
move and kill in gear again. Now I am ready to start my backcut
and very seldom and only on huge trees do I have to even get
any more pull. If I am getting within two inches of henge and not
seeing movement or gap widening, I have my wife start it and bump
it a little it starts to move and I cut a little more and motion her to pull
this works like a champ!
 
im of the understanding that 1/3 to 1/4 is all that is normaly required, howver on a back leaning tree, or a tree that has lost its crown a a scarf of 1/4 to 1/2 is a good practice to adjust for the lean or loss of crown weight.

i ALWAYS use wedges, to direct the fall, also a correct amount of hinge wood ( Approx 1/10th of tree diameter) variable each side depending on the lean.

when it requires you to pull the tree down a, simple 4 to 1 rigging set up, with prussiks works very well, and im a fan of this, 10 min to set up = professional and controlled fell.

however im always keen to hear if im useng bad practices, and open to any suggestions

thanks.


'You have to touch and tree, and feel it" Shigo

Are you guys logging white pine down there?
 
I thought I would add my 2 cents to this thread. My tree service is at the busiest time of the year right now, but have found some time to write this.
I estimate in my life time I have felled over 2 million trees, but when I switched from logging to running an urban tree service [where the good money is made] about 10 years ago,it took a city slicker arborist from Arbormaster to teach me some good proven techniques.
Everyone gets information on making a notch,backcut etc.from books which have evolved or revolved around the forest industry. The 1/3 notch goes back 100+ years. Notches were designed by the forest industry to reduce waste for the lumber making process. When falling blocks of forests or plantations the average lean of trees is towards the south east [anywhere on earth north of the equator],so felling in this field is fairly straight forward.

Now learn a little tree biology. Softwood trees support themselves with compression wood. Hardwood trees use tension wood for anchor support. Heartwood is not strong hingewood , only the sapwood offers strong hingewood. There is more sapwood in the hingewood of a 1/4 notch then in a 1/2 notch. Little things like these are big things when you are felling trees in an urban enviroment around houses and powerlines. Learn the stick trick technique to accurately estimate the height and length of a trees felling bed.Get a pull line up high enough in a big tree with your Bigshot and you can direct it anywhere with a Masdam rope come along. A 2 ft carpenters square seated in the apex of your notch is much more accurate then your saws felling sights for those really tight felling spots.

I could go on and on this subject. But my best advice is break away from the old forest industry standards ,learn a little from the arboriculture sector. A seasoned experienced chainsaw logger with his excellent body mechanics in chainsaw operation,knowledge of saw maintenence and endurance to get the job done would be one hell of a woodcutter if he also became a certified arborist or even just took a few Arbormaster courses in precision felling and cutting techniques. And don't forget about those 2 little super strong pieces of sapwood in your hingewood.
 
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sapwood

"only the sapwood offers strong hingewood."

This has a huge sliding scale. Strength here is a variable related to species, live wood moisture (drought influence - drier sapwood becomes heartwood in effect and looses strength), tree age, growth ring size etc. {Also how low one cuts on a live tree. The wood on any given tree is denser and stronger the lower one goes on the stump.}

Why not go with a 1/8th notch and get more sapwood that way than a 1/4 notch? That would result in just plain sapwood hinges on most trees.

Assuming the same hinge width, which the cutter can choose to alter of course, as the face comes closer to 1/2 there is more total wood in the hinge.
In stronger species in good health there is plenty of strength in heartwood to hold a hinge for the time needed to directionally control its fall.

In dead (and severe drought trees with live moisture between 80-120%) there is little strength in either of the woods. 'With the lean' is not just the greatly preferred option it can be the only option far more often than with the same tree alive or healthy.

When both sapwood and heartwood are substantially dried in dead trees there is no strength discussion. Think more limitations on what the cutter can do with a snag than a tree and that is based primarily on dryer woods being weaker, (even though the weights above are reduced and that can allow for easier wedging). Think thicker hinges and deeper faces. (If the wood strength isn't there to hold any hinge to the ground, understand that through experience before your first cut, then the knowledge that the hingewood is gone at 35-50% of the fall can help one predict if that is acceptable.)
 
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support

"Softwood trees support themselves with compression wood. Hardwood trees use tension wood for anchor support."

Did you mean to say: 'Softwood trees support themselves primarily with compression wood. Hardwood trees primarily use tension wood for anchor support.'

--------------

I thought they each used both.
 
Smokechase sorry I didn't explain myself a little better there in my last post, I didn't mean for you or anyone else to blow a head gasket responding to it. Like I said earlier I could go on and on about notches and hingewood , but the way this thread was going I didn't think it was needed anyway, but it sure turned your light bulb on upstairs though eh?

Willard:cheers:
 
smile

2,000,000 trees felled. If you average that out to even one minute per tree. working 24 hours a day round the clock never taking a break. That would be 1388 days. That is almost 4 years. Or if working a 40 hour week. cutting one a minute with no breaks that is 16 years.
I think you might be stretching the truth a little.
 
2,000,000 trees felled. If you average that out to even one minute per tree. working 24 hours a day round the clock never taking a break. That would be 1388 days. That is almost 4 years. Or if working a 40 hour week. cutting one a minute with no breaks that is 16 years.
I think you might be stretching the truth a little.

Believe me I've done it .In 20 years working as a full time piecework faller,working 8 hours a day ,5 days a week ,10-11 months a year ,in 10" average dia. wood ,some alot smaller ,some alot bigger. Easy 1 a minute.Do the math!!
And thats just from 1974 to 1994. I have been running my own tree service ever since. I guess to a hourly paid window installater guy that would be hard to grasp eh.

Willard
 
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Believe me I've done it .In 20 years working as a full time piecework faller,working 8 hours a day ,5 days a week ,10-11 months a year ,in 10" average dia. wood ,some alot smaller ,some alot bigger. Easy 1 a minute.Do the math!!
And thats just from 1974 to 1994. I have been running my own tree service ever since.

Willard

10" diameter wood? Son, you're not logging...you're weed-eating.
 
500 trees a day ,limbed and topped at 40-60ft.length average,from 40 below with 2feet of snow, to 100 above in summer. And helping my skidder operator choke it up to put it in the pile would have you PNW boys crying home for mama.

HAHA
Willard
 
I just sprayed Mountain Dew all over....LOL

Gas or electric? If electric, how long a cord was used?
What kind string was used?
Auto feed, or was it a bump feed, bump feed takes more time.

Ray
 
10" diameter wood? Son, you're not logging...you're weed-eating.

Ppffhht! Cough, aw crud now I gotta clean the keyboard again. My dog thinks I'm having a seizure.

2,000,000 trees in 20 years works out to 100,000 trees per year. That means 2,000 trees a week for 50 weeks. That means 400 trees per day. Wow! That means 50 trees per hour! You are a stud! You should have your own series on History. Heck you have to be a multi millionaire by now just by gross scale.
 
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