Tree-to-Ground Guying

treeseer · 23rd February 2008, 06:37 PM

Colleagues,

The old oak in the pictures has a wound ~50% of the circumference and ~6' high halfway up the trunk, on the side opposite the house. I can shove my entire handsaw in the gap between the woundwood and the xylem in several places along the edges of this wound. I can also shove it straight into some of the cracks, to a depth half the length of the blade.

Crown reduction is not a reasonable option given the age of the tree and the severity of the defect. The best management option seems to be a guy cable installed from a point above the defect and anchored into the ground. I reviewed the ANSI standards and the BMP's with the client, and our course seems clear. I have specified ground anchors only twice in the past, and cannot confirm whether these were installed, or recall seeing others.

Can you please refer me to successful cases of tree-to-ground guying? The client would like to know of some before going ahead. Sorry for the crappy pic of the wound; light was bad and i forgot to adjust the camera. 6 dead limbs around this wound and i have no clue what caused it. Theories?

playfordtree · 23rd February 2008, 06:52 PM

I am not an Arborist Treeseer only a humble tree lopper so i cant offer advice of that nature, but i am intersted to know if the tree is in such a bad condition and so close to the house why you wouldn't suggest euthanising the tree and starting again with a new tree?
Please educate me.
regards Simon.

Ekka · 23rd February 2008, 07:10 PM

I only see tree to ground guying on transplants where they want stability to help the roots make new ground and prevent blowing over.

What I dont understand is that you want to guy above the defect to a point below. If the defect or branches over the house fail they fall anyway or get hung up.

If the tree moves the guy wires will perhaps pull of heave on the defective area exacerbating the weakness.

How is a ground anchor going to help?

Regarding heavy pruning ... if you dont will nature do it for you?

bigshea13 · 23rd February 2008, 08:04 PM

nasty wound. ive used long bolts on severa
occassions for similar problems. you can get 5-6 foot lags and use large washer or scab boards on each end. put it threw several feet above crotch. even though its not in the correct spot it will if nothing less keep the leader from crashing on the house when nature severs it. another off the wall method is to purchase a long strand of cable and a large length of garden hose and another long lag with an eye. this is a last resort method but it works. wrap the cable around the upper {damaged portion} over a healthy crotch and down the back side of the tree{as if you were rigging it for removal} until you can find a stury spot for the lag and eye. place the garden hose over the cable{just to reduce friction on tree. connect the cable to eye. the set up will move with the entire tree and create less friction. the one main downfall to this is the visibilty factor but sometimes you can hide it well. if the leader is going to fail and you justg want to buy a little more time and still kepp the dwelling safe this will do it. when it does fail you just go up cut it out of the cable and go from there. kinda like a fishing night line for trees

arborjockey · 23rd February 2008, 08:10 PM

Do you have a picture of that?

bigshea13 · 23rd February 2008, 08:23 PM

if your talkin to me the answer is no. but if i get some time i can draw you up a diagram take a picture of it and post it if youd like

quercus · 23rd February 2008, 09:14 PM

I'd like to see your technique, Bigshea...

By not seeing the surrounding area of this tree, I'd suggest large concrete blocks placed at a distance from the tree that is larger then 1.5 times the crown spread. Estimating the size of the tree, I think they'll have to be somewhere between 25 to 30 metric tonnes of weight. Are there any other trees that may come in handy as an anchor point?
Placement of cables is also discussable. What will the main purpose be? holding the crown on the tree untill it eventually collapses of will you let nature have it's way and deflect it away from the house in case of a structural failure? For this last tech, you'll have to determine winds and speeds that go back as far as decades.
Reducing that windload could be accomplished by deadwooding, and crown opening on the inside. Wish I could explain it better.

Could you take some more pics of the wound and of the tree and it's surroundings?

What is your budget on this? very very important on this one.

Treelore · 24th February 2008, 12:17 AM

That wound seems pretty high in the tree. I am thinking ground anchoring is overkill. why not triangulate a cobra cable system to branches that are strong below the wound. Most of them seem to be growing up past the wound height. The picture doesn't tell everything but it seems you could cable from just above the wound in a spoke like pattern radially to other stronger stems????

treeseer · 24th February 2008, 03:15 AM

Quote:

Originally Posted by quercus

By not seeing the surrounding area of this tree, I'd suggest large concrete blocks placed at a distance from the tree that is larger then 1.5 times the crown spread. Estimating the size of the tree, I think they'll have to be somewhere between 25 to 30 metric tonnes of weight.

That much, eh?

Quote:

Are there any other trees that may come in handy as an anchor point?

No.

Quote:

Placement of cables is also discussable. What will the main purpose be? holding the crown on the tree untill it eventually collapses of will you let nature have it's way and deflect it away from the house in case of a structural failure?

Yes, plus the thought is that a cable would lessen movement and thus lessen the likelihood of failure.

Quote:

Reducing that windload could be accomplished by deadwooding, and crown opening on the inside.

The crown is very open already, due to the loss of the 6 branches. I deadwooded it yesterday.

Quote:

Could you take some more pics of the wound and of the tree and it's surroundings?

Yes that pic of the wound was crappy; I will try again with morning light.

Quote:

What is your budget on this? very very important on this one.

Not infinite, but the tree is of high value.

Ekka I hear what you are saying about the guys pulling "off heave" and that is a concern. I'm not sure what the tautness should be, or whether using two guys would alleviate or exacerbate that concern. O and ps I linked the client to this thread.

bigshea13 · 24th February 2008, 01:01 PM

best i can give ya. i dont have any cool diagram software so i drew it and photoed it.? the hose just reduces friction and the lag offers a small amount of structural support{cobras would be better} and the cable is attached to a fixed point on the tree itself. no need for cables to be strung across or threw the air or to large pieces of concrete somewhere in the yard. like i said..set it up like you were rigging with a cable.

treeseer · 24th February 2008, 03:23 PM

Quote:

Originally Posted by bigshea13

best i can give ya. i dont have any cool diagram software so i drew it and photoed it.? the hose just reduces friction and the lag offers a small amount of structural support{cobras would be better} and the cable is attached to a fixed point on the tree itself. no need for cables to be strung across or threw the air or to large pieces of concrete somewhere in the yard. like i said..set it up like you were rigging with a cable.

/well thanks for that effort, but...
1. I don't want to drill through the trunk below the defect.
2. The hose at the top crotch might not be enough to prevent damage, given the load on it.
3. I don't understand the physics involved. Something seems a bit off, and it is not in standards or bmp's.

hey quercus, we are talking about blocks of concrete IN, not ON the ground, right? Hence "tree-to-ground".

quercus · 24th February 2008, 11:25 PM

It seems like the only plausible idea. Concrete block pouring is not that difficult and I have done it before succesfully. The only thing that can be seen above the ground is the eye of the lag bolt, wich can be cut of when it is not longer needed. If accessible by crane the block can also be removed in one piece when the tree is gone. Also a block of 15 metric tonnes is not that big when it comes to concrete. I have poured blocks of 30 tonnes each.

What you do is you measure the volume and dig the hole. Then you punch in steel rebar of 1 meter long and 1 cm thick on various heights and on each side in the sides of the hole. Punch them in the sides with a hammer about 50 cm deep. So the other 50 cm can be locked in the concrete. Have a large lag bolt cut to length and put a stick in the eye and lay it on both sides on the ground on a brick. So the lag bolt is now suspended on the stick and will come about 20 cm above the ground. Be sure to dig at least 30 cm deeper then the volume you calculated. The blocks have to be at least square like a cube. Or even better is that they are deeper then what they measure on the surface.
Both blocks may not be more then 45 degrees sideways to the axis line of the tree target. Now pour concrete into it with a large mixer. When it hardens put the ground back on the top of the block. You now have a serious anchoring point. The more distance the more shallow is the angle of the cables to the tree. This is way stronger then a steep angle, and lets you dig in an area where there are no major roots. Anchor the cables as high as possible in the tree. I'd suggest at least 10 tonne MBS pre tensioned dynamic cobra bracing for this.... But still, we need a lot more pics.

Another possibility is that you have a steel cable with 2 loops spliced in the lag bolts and put the lag bolt completely vertical in the concrete block so that only the eye sticks out. The steel cable loop then comes above the ground as an anchor point. This is even stronger then what I mentioned before.

When completed this tech shouldn't cost more then 4000 usd.

Ekka · 24th February 2008, 11:39 PM

Yep, I did write about it here to.

Quote:

Originally Posted by Ekka

.... so they fly Klaus Mattheck out from Germany to have a look (and escape winter) who then suggests a cabling to some concrete blocks submerged in addition to reduction pruning ...

Also 1m3 of concrete weighs approx 2500kg

quercus · 25th February 2008, 12:28 PM

Yes I forgot to mention that. Concrete weighs between 2200 kg and 2500 kg's per m? depending on the mixture wich depends on the use.

treeseer · 25th February 2008, 10:55 PM

Quote:

Originally Posted by quercus

Yes I forgot to mention that. Concrete weighs between 2200 kg and 2500 kg's per m? depending on the mixture wich depends on the use.

quercus, your thinking is in line with what i had in mind but i do not see the cost near that high, and i do not see how cobra would handle that weight. given the lack of trunk flexibility and the weight of the top i expected to use 7 ton ehs steel cable.

TREE-SURFER · 26th February 2008, 10:18 AM

Quote:

Originally Posted by Ekka

I only see tree to ground guying on transplants where they want stability to help the roots make new ground and prevent blowing over.

What I dont understand is that you want to guy above the defect to a point below. If the defect or branches over the house fail they fall anyway or get hung up.

If the tree moves the guy wires will perhaps pull of heave on the defective area exacerbating the weakness.

How is a ground anchor going to help?

Regarding heavy pruning ... if you dont will nature do it for you?

Has Oak Wilt been considered? As the infected tree dies back the infected area, shutting down, say the limb, will cause it then to break off.
Since oak wilt causes drought-like symptoms, it may be easily confused with other stress-related factors. These factors include construction damage, drought stress, or insect colonization. In addition, oak wilt is often confused with the common springtime disease, anthracnose. In contrast to oak wilt, anthracnose causes spotting, curling and browning of the leaves in the lower canopy. In rare cases oak wilt may cause brown streaking of the inner sapwood. This streaking is a good diagnostic symptom for detecting infected trees. If any form of anthracnose is diagnosed, it will be better if the infected tree is removed and burned in order to reduce any further risk of infection to other trees.

23rd February 2008, 06:52 PM	#2 (permalink)
playfordtree Mature tree Join Date: Oct 2007 Location: Adelaide Australia Posts: 337	Re: Tree-to-Ground Guying I am not an Arborist Treeseer only a humble tree lopper so i cant offer advice of that nature, but i am intersted to know if the tree is in such a bad condition and so close to the house why you wouldn't suggest euthanising the tree and starting again with a new tree? Please educate me. regards Simon. __________________ I Drink Therefore I am.

23rd February 2008, 07:10 PM	#3 (permalink)
Ekka Eric Frei Administrator - Brisbane L5 (Dip) Hort Cert III Arb + some Join Date: Jan 2007 Location: Brisbane Posts: 6,869	Re: Tree-to-Ground Guying I only see tree to ground guying on transplants where they want stability to help the roots make new ground and prevent blowing over. What I dont understand is that you want to guy above the defect to a point below. If the defect or branches over the house fail they fall anyway or get hung up. If the tree moves the guy wires will perhaps pull of heave on the defective area exacerbating the weakness. How is a ground anchor going to help? Regarding heavy pruning ... if you dont will nature do it for you? __________________ Remember to use the "search" function, if you have answers/questions post them so everyone can benefit. Free Tree and Green Industry Link Directory Qualified Brisbane Tree Lopping Brisbane Tree Care, Consultations and Arborist Reports Forum Sponsors

23rd February 2008, 08:04 PM	#4 (permalink)
bigshea13 Mature tree Join Date: Nov 2007 Location: hiding Posts: 386	Re: Tree-to-Ground Guying nasty wound. ive used long bolts on severa occassions for similar problems. you can get 5-6 foot lags and use large washer or scab boards on each end. put it threw several feet above crotch. even though its not in the correct spot it will if nothing less keep the leader from crashing on the house when nature severs it. another off the wall method is to purchase a long strand of cable and a large length of garden hose and another long lag with an eye. this is a last resort method but it works. wrap the cable around the upper {damaged portion} over a healthy crotch and down the back side of the tree{as if you were rigging it for removal} until you can find a stury spot for the lag and eye. place the garden hose over the cable{just to reduce friction on tree. connect the cable to eye. the set up will move with the entire tree and create less friction. the one main downfall to this is the visibilty factor but sometimes you can hide it well. if the leader is going to fail and you justg want to buy a little more time and still kepp the dwelling safe this will do it. when it does fail you just go up cut it out of the cable and go from there. kinda like a fishing night line for trees

23rd February 2008, 08:10 PM	#5 (permalink)
arborjockey Semi-mature vigorous tree Join Date: Dec 2007 Location: hawaii. ohio. oregon. california Posts: 127	Re: Tree-to-Ground Guying Do you have a picture of that?

23rd February 2008, 08:23 PM	#6 (permalink)
bigshea13 Mature tree Join Date: Nov 2007 Location: hiding Posts: 386	Re: Tree-to-Ground Guying if your talkin to me the answer is no. but if i get some time i can draw you up a diagram take a picture of it and post it if youd like

23rd February 2008, 09:14 PM	#7 (permalink)
quercus Mature tree Join Date: Nov 2007 Location: belgium Posts: 426	Re: Tree-to-Ground Guying I'd like to see your technique, Bigshea... By not seeing the surrounding area of this tree, I'd suggest large concrete blocks placed at a distance from the tree that is larger then 1.5 times the crown spread. Estimating the size of the tree, I think they'll have to be somewhere between 25 to 30 metric tonnes of weight. Are there any other trees that may come in handy as an anchor point? Placement of cables is also discussable. What will the main purpose be? holding the crown on the tree untill it eventually collapses of will you let nature have it's way and deflect it away from the house in case of a structural failure? For this last tech, you'll have to determine winds and speeds that go back as far as decades. Reducing that windload could be accomplished by deadwooding, and crown opening on the inside. Wish I could explain it better. Could you take some more pics of the wound and of the tree and it's surroundings? What is your budget on this? very very important on this one.

24th February 2008, 12:17 AM	#8 (permalink)
Treelore Banned Join Date: Feb 2008 Location: Brisbane Posts: 115	Re: Tree-to-Ground Guying That wound seems pretty high in the tree. I am thinking ground anchoring is overkill. why not triangulate a cobra cable system to branches that are strong below the wound. Most of them seem to be growing up past the wound height. The picture doesn't tell everything but it seems you could cable from just above the wound in a spoke like pattern radially to other stronger stems????

24th February 2008, 11:25 PM	#12 (permalink)
quercus Mature tree Join Date: Nov 2007 Location: belgium Posts: 426	Re: Tree-to-Ground Guying It seems like the only plausible idea. Concrete block pouring is not that difficult and I have done it before succesfully. The only thing that can be seen above the ground is the eye of the lag bolt, wich can be cut of when it is not longer needed. If accessible by crane the block can also be removed in one piece when the tree is gone. Also a block of 15 metric tonnes is not that big when it comes to concrete. I have poured blocks of 30 tonnes each. What you do is you measure the volume and dig the hole. Then you punch in steel rebar of 1 meter long and 1 cm thick on various heights and on each side in the sides of the hole. Punch them in the sides with a hammer about 50 cm deep. So the other 50 cm can be locked in the concrete. Have a large lag bolt cut to length and put a stick in the eye and lay it on both sides on the ground on a brick. So the lag bolt is now suspended on the stick and will come about 20 cm above the ground. Be sure to dig at least 30 cm deeper then the volume you calculated. The blocks have to be at least square like a cube. Or even better is that they are deeper then what they measure on the surface. Both blocks may not be more then 45 degrees sideways to the axis line of the tree target. Now pour concrete into it with a large mixer. When it hardens put the ground back on the top of the block. You now have a serious anchoring point. The more distance the more shallow is the angle of the cables to the tree. This is way stronger then a steep angle, and lets you dig in an area where there are no major roots. Anchor the cables as high as possible in the tree. I'd suggest at least 10 tonne MBS pre tensioned dynamic cobra bracing for this.... But still, we need a lot more pics. Another possibility is that you have a steel cable with 2 loops spliced in the lag bolts and put the lag bolt completely vertical in the concrete block so that only the eye sticks out. The steel cable loop then comes above the ground as an anchor point. This is even stronger then what I mentioned before. When completed this tech shouldn't cost more then 4000 usd.

25th February 2008, 12:28 PM	#14 (permalink)
quercus Mature tree Join Date: Nov 2007 Location: belgium Posts: 426	Re: Tree-to-Ground Guying Yes I forgot to mention that. Concrete weighs between 2200 kg and 2500 kg's per m? depending on the mixture wich depends on the use.