opinion on hazard tree assessment

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Greenleaf

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Looking to see what some other knowledgeable assessors would think about this tree which I've been contacted to assess. pictures attached.

The tree has substantial lean >20% towards house, with no visible rooting problems, ie. no lifting root mat etc. From a distance the tree is correcting itself 'sweep'. The reason why I was contacted to look at the tree is because someone noticed a spiral crack (not open) which is on the windward/ tension side of the tree. Banged the tree with a mallet and it sounds like it is sound, and it appears that there is callus forming around the crack/fissure.

Wondering what your opinions would be with a tree like this. A very obvious target being the house. Following the criteria from the WCB Wildlife/ Danger Tree Assessment process because the crack is not open (<2cm), nor can I determine how far it extends into the cross-section of the tree, and there are no obvious rooting problems the tree would be a low/moderate risk and I'd recommend monitoring.
 
I would call it a moderate to low increase in risk of failure from "the perfect tree".

As you note, the cause of the lean, throw is old, is self correcting.

DO you known the history of the area? Was there a high wind event back then.

There is no decay, or seepage from the crack, could it be relatively recent lightning?

From your pictures I would recommend keeping the tree, and if they are concerned with future throwing, install a plumb bob they can use to measure any movement
 
When in doubt..

How about pruning it?> Reduce weight on ends of branches, take down the top a few whorls, maybe remove some branches to reduce windthrow...
 
Top it by 1/3!

Come on now, that was too funny! :jawdrop:

Seriously, what sticks out in our minds right off the bat from the first picture is its vulnerability to both wind and lightning due to its solitary status. Either one of which could have caused a similar injury. I think I would feel better with a reduced sail area...thinning, thinning, thinning NOT topping. LOL Even small amounts can help.

How far up does the fracture go?

In our area, most of the wind thrown spruces and pines fall to the east (our prevailing winds are out of the west). You mentioned the crack was on the windward side. What is the history of windthrow in that area? That could increase or reduce the risk.

D and S Mc
 
I'm with Clearance on this, take er down. That top will come off someday and go through the roof. Big tree+ catching lots of wind+ leaning over house+ crack started= takedown. Unless of course the homeowner is against it. Then, well.......I would go with the standard 1/3 topping. Ha.
 
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Our prevailing winds are out of the west as well, much of the spruce in the neighborhood have a gradual lean eastward. There have been multiple wind events here over the last 50 years which caused windthrow in different parts of town. Mainly previously forest fir with low taper. We are located in a tighter section of the columbia valley and can get some pretty violent storms out of the hills.

The thought of lightning was in my head as well. If that were the case I'd prefer not to be the arborist who climbed and pruned the tree that failed 6 months later. Pretty bad for business. I live 5 blocks from here and just removed a large forked spruce in my front yard a few weeks ago, was about the same height and age, 95years. I'm not worried about culling a bad tree, but like to be fairly certain it is a bad tree. This tree is located fairly close to the columbia river and when the water level rises the water table will come right up in that section of town.

Clearance you remind me of lots of my friends. Always need both sides of a coin on a decision.
 
Cracks = Decay

Decay = Bad

Lean = Bad

House = Target

I'm no pro, so I won't yes or no... But I sure wouldn't want that leaning towards my house....
 
If your going to sign of on it

Looking to see what some other knowledgeable assessors would think about this tree which I've been contacted to assess. pictures attached.

The tree has substantial lean >20% towards house, with no visible rooting problems, ie. no lifting root mat etc. From a distance the tree is correcting itself 'sweep'. The reason why I was contacted to look at the tree is because someone noticed a spiral crack (not open) which is on the windward/ tension side of the tree. Banged the tree with a mallet and it sounds like it is sound, and it appears that there is callus forming around the crack/fissure.

Wondering what your opinions would be with a tree like this. A very obvious target being the house. Following the criteria from the WCB Wildlife/ Danger Tree Assessment process because the crack is not open (<2cm), nor can I determine how far it extends into the cross-section of the tree, and there are no obvious rooting problems the tree would be a low/moderate risk and I'd recommend monitoring.

Couple thoughts for you...

First off, make sure you have errors and omissions on your insurance policy; general liability will not cover you for assessments. Second, the new standard for tree assessment in the urban area is the hazard tree assessor course put on by ISA {PNW} and WCB. The new course does not have a lot in common with the wildlife tree and hazard tree assessment course designed for forest operations and worker safety.

I would want to know the extent of the crack before making the call. How high does it go? How far in? Make sure it is not a shear plane fracture [all the way through the wood]. My understanding is spiral fractures are the most structurally compromising of the fractures. Thinning and reducing the sail area
of the tree will increase the elliptical movement of the stem in wind which will exasperate a spiral fracture weakness. I would not thin very much and most of that on the lean side.

Where are you in the Kootneys, Trail, Nelson, Castlegar ? If so, you can get some very sever winds and, by the looks of it, that tree is not sheltered.

I would spend a little more time with that fir before recommending retention.
 
Thanks Mitchell. I am actually enrolled in the Tree Risk Assessors course in Vancouver next week. I've looked at 100's and 100's of trees around campgrounds and trails, but this is the first really tricky decision I've had with a tree that could compromise a house. Makes it difficult when there are no other qualified assessors around to bounce ideas off, so that's why I've posted it on here.

As far as the crack goes, it only extends as high as you can see in this photo. Like I said it is not open, and therefore I can not determine how far it extends through the tree. Not sure that sticking an increment bore into it is going to tell me very much.

As far as liability goes, it seems to me that the best way to protect yourself regardless of insurance etc. is to do your due diligence and follow some sort of standard decision making guideline. The new Tree Risk Assessor's course seems to leave open alot more flexibility for assessors to lean either way as long as you justify it. The only way I could reduce the liability to nil on my end would be to remove the tree just in case. In which case not knowing what is going on inside makes me question rigging the top out above the house?

By the way I'm located in the North....Golden.
 
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Greenleaf, let us know how you like the Tree Assessors course S Mc is debating taking it.

Remember try not to impose your opinions on the clients. State the facts. That is what they are looking for. Everyone's level of acceptable risk is different and balanced by different criteria. They need you to give them the facts and with those facts any decisions are theirs to make.

As a side note, I have worked on many lightning struck trees and they ranged from the scariest trees imaginable to mere boo-boos. Just saying the possibility of a lightning strike is in itself not a diagnosis but an observation.

New reports we have read are demonstrating that reduction of overall tree crown (raise skirt, reduce top) reduces wind sail factor better than thinning. But as this tree didn't appear to be a good candidate for that, we didn't mention it.

D and S Mc
 
New reports we have read are demonstrating that reduction of overall tree crown (raise skirt, reduce top) reduces wind sail factor better than thinning. But as this tree didn't appear to be a good candidate for that, we didn't mention it.

My understanding of this is that it allows the wind in throughout the canopy without reducing the actual surface area. This will change the action of bend, where raising will change the moment of bend.

I've found that thin and reduce puts less stress on the tree overall then a raise and reduce. You take some of the leverage off the stem/branch end, but do not alter the moment of bend as much.

One problem with changing where it bends, is you also remove the dynamic mass that will generate the new reaction wood that it will need to compensate.

Spruce are the hardest to work with this way, there really is not much you can do vis reduction, without making future problems and ruining the aesthetics.
 
Nice Country

By the way I'm located in the North....Golden.

Not sure if you have any interior wet belt around you there? Not to far from you there, in Revelstoke, I was surprised to get into cedars with massive 12 foot butts. In fact I think my avatar picture is from there.

If you have an increment borer It would show you how deep the crack is. If you do remove it [I'm sure you know] to increase stability, you can leave the branches on until you get the top out.

Your right though it takes a whole different approach and mindset to look for tree retention. I am fairly new to considering tree retention with defects and targets as a possibility myself. In my past any suspect tree was automaticly removed. Which is what the new course is designed to address.

The new course is well worth your while, I defiantly recommend it. Who is teaching your course; Dr Dunster is very well informed and he makes it worth while just to here the lectures. I believe he designed the course himself.

They are not kidding when they say to do the pre reading. I personally did not thinking it would be another unrealistic super objective WCB show up and get the piece of paper kinda deal. It is not, the course parameters are subjective so you have to prove you know what you are doing. The test is written answer. Most guys I know who have done it, myself included, were not sure if we passed the test. Know your common root and butt rots. Also, have an idea of how compartmentalization of decay varies in tree species; IE, alder = terrible, maple = ok, cedar = very good etc.
 
What a grand tree!

It is certainly deserving of a 110 percent effort towards salvation............if it were out in the middle of nowhere.

Honestly, this makes great conversation. I learn so much that inspires me reading these types of threads.

Meanwhile, I’d take it down.

My simple outlook is to plant trees in lieu of saving something like that, just for the sake of saving, or attempting to. Planting is very rewarding, and makes so much better sense to the average homeowner than always looking at that leaning tower of homewrecker wondering if that tree guy really has a clue or not.

I think it is advantageous to look at it from their point of view and perhaps that of the neighborhood as well. It makes no sense to save such a tree to most people.


I look at that first picture and imagine the tree gone. I don’t like that at all…..there is something missing. Ah, then I imagine a nice choice tree in its place. There, that’s better.

No worries…nice landscape.
 
Thanks Mitchell. I am actually enrolled in the Tree Risk Assessors course in Vancouver next week. I've looked at 100's and 100's of trees around campgrounds and trails, but this is the first really tricky decision I've had with a tree that could compromise a house. Makes it difficult when there are no other qualified assessors around to bounce ideas off, so that's why I've posted it on here.

As far as the crack goes, it only extends as high as you can see in this photo. Like I said it is not open, and therefore I can not determine how far it extends through the tree. Not sure that sticking an increment bore into it is going to tell me very much.

As far as liability goes, it seems to me that the best way to protect yourself regardless of insurance etc. is to do your due diligence and follow some sort of standard decision making guideline. The new Tree Risk Assessor's course seems to leave open alot more flexibility for assessors to lean either way as long as you justify it. The only way I could reduce the liability to nil on my end would be to remove the tree just in case. In which case not knowing what is going on inside makes me question rigging the top out above the house?

By the way I'm located in the North....Golden.

If you decide to remove it you could put some good ( 10,000 # ) ratchet binders on it as you go up. I would use at least 4. The IML resistogragh might be a good investment if you plan to do a lot of assesments like this. Is there any way to one cut it? Put the binders on and wack it. Replant
 
You cant reduce it?

I saw on of the posts that spruce are diffcult to work on and hard to reduce...I agree they SUCK to work on but they can be reduced. Super easy with a bucket handsaw and a pair of handsnips. Take the top down a few whorls (1-5) depending on aesthetics and how concerned you are with reducing top leverage and then snip the top to make it retain its original shape (A-shapeish) and then go through with your snip and suck int hos branches as far as you feel comfortable doing. Wherever you make a cut, the laterals directly behind it on the branch will take charge. Then next year...you go back re-traint he top into a central leader, removing competing tops and then snip back the two shoots on every branch that elongated where you made the cut last year...IMO the only way to keep spruces small, due to lack of epicormic/dormant growth. If you have aethetic leeway then remove and entire branch if possible. Any bit of stress of the stem will help.


This is the way I would do it if I wanted to keep it. If it was at my house...cuter down no questions asked I hate spruces...
 
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If you decide to remove it you could put some good ( 10,000 # ) ratchet binders on it as you go up. I would use at least 4. The IML resistogragh might be a good investment if you plan to do a lot of assesments like this. Is there any way to one cut it? Put the binders on and wack it. Replant

No chance of cutting it down in one shot, have powerlines in both directions I'd want to steer it to. Likely if they decide to go ahead with the removal I'll leave the lower canopy alone and cut a corridor to lower the top through. Makes it slower but will definitely reduce the forces on the truck when the top comes to bear on the line. May throw one strap around the base for security, but I'd really be surprised to see that peal open.

Thanks again for all of the feed back. Much appreciated.
 
850 plus around 150 for the stump. Oh? I thought we were bidding on it. What is the address? I will stick a flyer in the door.
 
I saw on of the posts that spruce are diffcult to work on and hard to reduce...I agree they SUCK to work on but they can be reduced. Super easy with a bucket handsaw and a pair of handsnips. Take the top down a few whorls (1-5) depending on aesthetics and how concerned you are with reducing top leverage and then snip the top to make it retain its original shape (A-shapeish) and then go through with your snip and suck int hos branches as far as you feel comfortable doing. Wherever you make a cut, the laterals directly behind it on the branch will take charge. Then next year...you go back re-traint he top into a central leader, removing competing tops and then snip back the two shoots on every branch that elongated where you made the cut last year...IMO the only way to keep spruces small, due to lack of epicormic/dormant growth. If you have aethetic leeway then remove and entire branch if possible. Any bit of stress of the stem will help.


This is the way I would do it if I wanted to keep it. If it was at my house...cuter down no questions asked I hate spruces...

How about making it into a giant screw? Like a spiral stair case. It would be awesome with lights and a flag on to.
 

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