At what point is decay a death sentence?

[ddhlakebound]

I looked at the largest red oak I've ever seen today. Not terribly impressive height wise, but it's massive trunk would be more at home in the Pacific NorthWest.

I didn't have a tape, but I used my throwball line for the estimated circumference. 15' at breast height. 24' at ground level.

It sits between a credit union and sidewalk/street. Its top has broken out at 50-55', and its probably 24" diameter there. The broken top reveals a hollow in the top of the stem, extending downward for an unknown distance.

The trees owner requested an estimate for removal, because an ISA CA has stated it's a hazard and must come down. When the owner read the report to me, there was nothing included about how the CA had determined the trees ability to support itself, or lack of, other than visual inspection from the ground. No climbing inspection that I'm aware of, no resistograph, just a CYA statement of "Its a hazard, take it down."

This tree is truly historic, and I'd really like to see it stay alive, unless it really needs to be removed. So would the owner, but he has considerable liability concerns with this monster located at a place of business. In order to keep it, he needs verifiable scientific method to determine wether the tree is sound enough to remain.

I'm not certified yet. 9 more months and I can sit for the exam. I don't have a resistograph, heck, I don't even know how useful one would be on a tree this massive.

I advised the owner to get 2 more inspections from CA's, and go from there. I also declined to give an estimate. It's just too big for me to handle. So did the other guy who arrived at the same time to look at it. Maybe I should have named the thread "Monster tree up for grabs...":monkey:

So.....How much decay can a tree have, and still remain sound enough to be confident of it's saftey?

Is there any way (ultrasound or something?) to determine the amount of decay in a tree without drilling?

 

[Canyonbc]

Sorry, i am not a CA...and dont have any suggestions..

But do you have any pics....

That would be a awesome oak to see in Missouri...and in the city...sounds gorgeous..

Def. sounds like a historical figure for the town

 

[Ekka]

There's many judgements made like that, no risk if it's gone, and if it's not protected then there's no argument I suppose.

Also, the owner could favour a one off removal fee vs ongoing costs with risks.

If the arborist were to argue the case for retention then more evidence is required to cover his ass. That's the way it goes many times.

There's some rules of thumb that you need 1" wall thickness for every 6" of diameter (bark doesnt count). However that method although a rule of thumb doesn't take into consideration the trees bulk/volume/taper. For a tree that diameter and that height you could go less, there's no real scientific 100% proven method.

Then there's the puller blokes. They stick sensors on the tree and load a rope then measure flex and come up with a plan which is usually reduction. But I dont need all that BS to tell you reduced trees are less likely to blow over ... however reduced trees also have foliage removed and wounds inflicted that start other problems.

The tree has already had it's head blow off, that's a natural reduction, perhaps trim that properly and inspect the rest carefully, check decay wall thickness etc and try to see why the top blew off.

 

[Kneejerk Bombas]

Got some pictures?

 

[beastmaster]

I'd like to see a picture too. It sounds like an awesome tree. One of the main consideration in hazard tree evaluation is potential targets if it should fail. A decayed tree on a big private property isn't evaluated the same as the same tree in a school yard. There's lot of liability issues for everyone concerned. That's offten the overriding factor.

 

[Mr.Roehler]

I would sound the wood and do a tree hazard evaluation according to the form and see where it stands on that. I know it's rough cutting down a gorgeous tree like that but sometimes for safety reason for the location it's best.

 

[treeseer]

How about selling the owner on you doing an aerial inspection? Maybe 2 hours time to climb it and photograph the defects. Take up equipment to measure the cavity; a stick and a tape measure would do. Post the pics and the measurements here.

That, and/or hire me to assess the risk; I will be up there in early March at st. joseph for the isa chapter meeting. pm me and I'll send my cv you can fwd to the owner.

Dan, I hate to break it to you, but many asca consultants would do the same nonsense as the ca--look at it from the ground and do a cya removal recommendation. Chickenspit Chicken Little tree work. :censored:

One view on risk attached fwiw.

 

[ddhlakebound]

Thanks for all the replies and suggestions. I searched ASCA consulting arborists, and the only one listed here works for the company who did the original assessment. Not sure if he was the guy who wrote it or not. I'll check on that monday when I talk to the owner again.

I drove by the tree again today, still didn't have a camera with me, but looked at it from a perspective I should have yesterday. I'm so used to seeing wrecked trees from the ice storm I didn't look at much else than the trunk and the obvious fault yesterday.

It has been reduced, I don't know if it was proscribed, or from cleaning up ice storm damage. All the upper canopy has been headed back to a lateral, probably at 6-8" diameter.

The main fault is a little lower than I said, probably 40-45', it looks like the larger of 2 codominants split out, exposing the hollow. The one that stayed has died, apparently as a result of the split.

I'll try to get pics early next week, and see if the owner is willing to spend to find out if the tree is saveable. If he is, I'll go ahead and climb it for airborne pics and measurements of the decay.

Treeseer, I appreciate the offer, and I'll pass it along to the tree's owner. Thanks for the links also.