Hinge Thickness For Falling Large Diameter Trees?

[lone wolf]

Hello,

Happy Thanksgiving everyone! Here is an interesting question to ponder over turkey and football.

The Forest Service guidelines specify a falling hinge thickness of 10% DBH as a maximum. The 10% number works out pretty good for trees under 20" or so. But what about a 48" tree? 10% is 5 inches which sounds like a near impossibility to wedge over, especially if the tree is dead and has no lean or weight. Think about trying to break a true to life 5" x 48" piece of wood. Think about a huge dead, dry piece of red oak.

Here is the situation: The tree in the photo is right next to a hiking trail and has been dropping widow maker limbs onto the trail. Due to this the trail section monitor has asked me to evaluate the safe removal of this tree. The tree was supposedly alive a couple of years ago until the town put a sewer line in the vicinity of the tree and damaged the root system.

As a disclaimer I have not laid eyes or hands on the tree as of yet. I do have it on good authority that the DBH was actually measured at a little over 48". The diameter tape was only 12 foot and that was the end of the tape!

For mitigating resources/measures we have access to rope rigging and a Tu-17 Griphoist so this could belay having to wedge the tree over.

Your thoughts?

View attachment 1222720

Can you rent a towable lift?

 

[Firewood]

Despite all the good advice here, can you tell us how it goes at the time of felling/removal? if possible could you educate on the techniques used for removal I would love to hear more about this

 

[J D]

Despite all the good advice here, can you tell us how it goes at the time of felling/removal? if possible could you educate on the techniques used for removal I would love to hear more about this

Preferably not in the form of a "what not to do"

 

[Firewood]

Preferably not in the form of a "what not to do"

Very much so! The best outcome would be tree down zero injuries

 

[capetrees]

Heavy rigging line as shown in blue the tree where there seems to be some decently strong trunk. I don't know whats to the right but pull to that direction to fall in what seems to be a field (?). With a long enough rope, maybe attach to a heavy piece of equipment or truck to pull it over? Or maybe if there's a sizeable tree, use a pully to offset the direction of the pull. With no lean and no offsetting weight to one side or the other, any pull from any direction will pull the tree to that direction.

1/3 notch, cuts the sides of the notch in from both sides to make sure they're free, pull on the rope and cut the backside. I do it all the time with long dead white and red oak that have died from gall wasp or gypsy moth damage/death.

 

[Del_]

Looks like it already has the buzzards up there waiting LOL

Dang, are those buzzards?

That tree is bigger than I thought.

 

[ZeroJunk]

Dang, are those buzzards?

That tree is bigger than I thought.

Crows maybe. They will still eat the remains.

 

[SteveSr]

Like you say, the target zone includes the use trail, then what ever you do when you touch it, it is best to finish it for creating a hazard to the public users of the trail.

Right now the trail is re-routed off of our ROW and away from this tree. We would like to put it back on our ROW but if we can't we can't.

 

[SteveSr]

Despite all the good advice here, can you tell us how it goes at the time of felling/removal? if possible could you educate on the techniques used for removal I would love to hear more about this

Will do. Currently scheduled for December 16th. Weather permitting.

 

[SteveSr]

Can you rent a towable lift?

A lift couldn't get in there.