Make a decision based on what the tree experts who have already viewed the tree in person said.

Probably remove the whole tree.

If the better side is starting to loose bark, it's not far behind what the other is doing, declining. And cutting one side off will offer another opening for mold and pathogens to enter what's left.

Plant another tree in it's place and enjoy watching it grow.

use the camera/photo button under the box you type a reply in ... wait until the pic comes into focus.. before hitting send ... be patient.. some times there is a lag ... keep trying ... else all we are doing .. is guessing ...

the most important question is .. wait for it ... if it falls down ... will it fall on anything important??? ... if so... get rid of it all ...

if its out on the back 40 ... who cares.. let it figure it out on its own ...

the base question you ask... if i read it right.. is whether.. opening new wounds on the healthy part ... will cause that part to end up like the other part ... and who knows ... and then you are right back to what it will fall on.. and what your risk level is ...

and to be clear.. if it will only fall on your hated neighbor.. that is NOT a reason to do nothing.. lol ...

ken

ps: kind of surprised.. your two experts??... couldnt decide whether it was a deciduous or evergreen tree.. whats that all about???? ... were these certified tree peeps.. or some dudes with chainsaws ... your best bet.. might be to hire an ISA certified arborist ... and get some useful info ... money well spent.. to get useful info.. to make a decision ..

https://duckduckgo.com/?q=ISA+certified+arborist&t=ffcm&ia=web

One of the arborists only viewed the tree in photos; the other stopped by, but it was last year when the tree was still doing fairly well (sprouted lots of new leaves). Agree it is strange that the two certified arborists identified the tree differently, but perhaps it's because one did not stop by to view it in person.

On a practical level, Bill in MN is right that it would be best to cut it all down. Having said that, we might do it in two stages over a few years; maybe plant a new one nearby and let it get established before removing the second trunk.

Am going to try to upload the photo again. I reduced the file size of the photo this time in case that was an issue.

Oh yeah. Common for our native trees. So many like Oaks,Sycamores and especially Bay tree's...split,one or more big trunk falls and what's left goes on fine. Usually.

Nonetheless the one with the peeling bark is a goner. Remove it. For the rest it's your call if say the root system is compromised or -again - a natural process I see all the time in the local woods.

Yes to Floral's comment.. Dead trees support far more life than live ones! We need to adjust our aesthetic to see their beauty and integrate them into our designed landscapes. You can admire the form of the trunk and branching, or consider it a scaffold for a climber. If there's enough sun, how about a rambling rose?

As others said, not uncommon. Many forest oaks here have a "stub" at the base where a subordinate trunk died & broke off.

bengz6, most of the oaks around here (whether live oak or deciduous) have multiple trunks, and it's common to see an oak tree with one or more stubs along with the remaining live trunks.

Last year a huge branch and its offshoots sprouted no leaves, so we had that part removed, hoping it might help the rest of the tree. It's apparent it won't survive in the long run.

floral and kitasei, the trunk would have to be removed as it right next to a street (not terribly busy but needs to be clear) on one side. There's a propane tank behind it and a driveway at the front of the photo.

I see. Probably going to have to go then. Perhaps you could leave a felled section to rot on the ground?

It's a matter of time. Love the tree so hope to preserve it a while longer. Yes, we could leave a felled section to rot, and there are plenty of rotting dead trees in the surrounding wilderness area too.

The main theme here is...don't kill the rest of the tree because its shedding an extra trunk.

But for safety..and no unpleasant surprises take out what's near dead anyways.

' don't kill the rest of the tree because its shedding an extra trunk. '

Never heard of such a thing. Trees don't shed some parts so the rest continue to thrive. The trunk on the right has been suffering for some time and is as good as dead and the OP said the other side is beginning to lose bark too, which tells me that part is also in decline. Most likely from the same disease.

Leaving diseased dead wood lying around is not a good idea as these diseases can start in at the base of other trees and infect them also.

Removing the sick tree and cleaning up the dead wood is the best remedy and starting a new tree or three is good conservation practice for the future.

Well,I see them do that all the time. There are park Sycamores that shed half the trunk decades ago and the tree left went on fine.

If the healthy tree has a disease...cut it down. Can't argue with that.

' Well,I see them do that all the time. '

I'm not arguing that it doesn't or can't happen but it could be something else entirely, happening with those. We'd need more evidence to determine that.

Judging by the OP's description that the more healthy side also is losing bark and all the water sprouts you can see in the picture on the lower third of the crown on both trees, these are sure signs of failing trees imo.

I'm not entirely against planting replacement trees now and removing the tree in question down the road but there is a chance, albeit slim, of the old tree infecting the new ones, if they are of a similar species. You just never know for sure. I always like to play it safe and remove the questionable trees, leaving a spacious area to plant several more, with no competition to the new trees for light or rooting area.

:^)

The dieback of one trunk usually indicates the vascular system of the tree has been compromised by a fungus. If you leave it alone, the fungus spores will spread through the rest of the tree eventually. Better to cut it down and remove it so the remaining trees can remain healthy. We all know how too much dead wood on the ground contributes to fire fuel. Some is need for habitat for insects and other animals, but there should be a balance.

We are strongly leaning towards removing it all. Our neighbor across the way said a few of his oaks were afflicted by fungus some years ago. He tried to save them but they didn't make it and eventually had to be cut down.

I was holding out hope for a while as I had seen a gigantic old oak tree with a large section of missing bark (some said the tree was probably 200 years old) by a local school. A few months ago, that beautiful old tree was removed. I doubt our tree could last more than a few years.

It might have Sudden Oak Death disease. That's about as fatal as can be..although some have had some success injecting the tree's with some cure arborists and botanists have used. I don't recall what it was right now.

Impossible for me to say by photographs..but I do say that I've seen wild native trees split off trunks and go on fine. Some had hollowed trunks. That's the problem here..if you want a perfect looking tree? It's passed that. If you just want nature to do what it does..you remove what is obviously dead and leave the rest and wait and see.

I think since you say a fall of the whole thing would crush things...remove the whole tree sounds best. Replant a tree not susceptible to SOD.

' Impossible for me to say by photographs '

Thin, spindly tops and other said symptoms with multiple trunks originating from the same stump, indicates a common malady affecting all said trees.

' Some had hollowed trunks '

Exactly what you don't want but trees that are struck by lightning or broken off by wind and are otherwise healthy and sound are less likely to cause other problems in the future and may go for decades.

' remove the whole tree sounds best '

um, yes. There'll be plenty of other things to do in the future without that job hanging over your head. No pun intended. :-)

I'd say that if you don't like looking at the tree cut it down. Did anyone bring up that it'd be cheaper to take the thing down all at the same time than to have it done on separate occasions. Of course if you're doing it your self it might be easier on the body to spread out the work load. And it would help to preserve any firewood if it were still alive.

-- I've seen wild native trees split off trunks and go on fine. Some had hollowed trunks. --

We have some like that too and they are fine with intact bark.

-- Did anyone bring up that it'd be cheaper to take the thing down all at the same time than to have it done on separate occasions. --

You are right that it would save money to take it down in one go. We will weigh all the options.

It's a tough decision no matter how you look at it. Hard to remove the beauty of a large tree. Then again, it's the cycle of life. One thing that has served it's purpose removed to construct a plan for a better future.

Funny thought, years ago (maybe 40+) when I first lived out in the woods on 40 a., Loggers clear cut sections of that land. Today, you can't tell that by looking and is almost ready to be harvested again. I know because I was there. :-)

Over the years some of the larger trees have succumbed to disease, animal damage and flooding. But in the grand scheme of things, the woods has been a healthy, growing environment, providing animal habitat, fire wood, lumber and natural beauty, with the emphasis on natural beauty. :-)

Hard to generalize about the many shoots. We had a drought for years. Even my Ash tree lost a couple of large branches. With the El Nino rains in California two of the last three years, many trees are luxuriating in the abundance of ground water and rains late into spring.

I didn't consider the years of drought out there, mostly because it was never brought up. But in my neck of the woods, once damaged that heavily from drought, the tree is open to a plethora of other problems, mostly caused by diseases taking advantage of the trees weakened condition. Most of them never amount, in stature, close to what an undamaged tree will achieve in the same amount of time. In the right kind of location and environment, some will do just fine.

In park trees that's true..but setbacks are what give character to wild trees that don't ask for any help from man. Broken branches..termites on this..Lightning..fire..

I see many a wild tree that looks gorgeous and I know in a garden it would have been pruned of that wild zig low branch "For its own good" long ago.

But this tree says the OP is near something crushable..so I get taking it all down.

Yup, safety first.

We've given the OP every angle to look at, that's for sure. :-)

Beauty is in the eye of the beholder and different climates/locations can call for different options.

Laurie,

Please let us know how this all turns out. :-)

oh my ... great debate .. some relevant.. some not ... lol ...

just be done with it all ... plant a bunch to replace it.. looks like you have space ...

diversify ... dont plant all of one kind ...

think of it this way.. just nice round numbers .... 1000 bucks to remove it all ..

or.....

850 dollars to surgically remove half without damaging the rest .. and a few years later.. perhaps paying another 1000 to remove the rest ... cuz prices never go down ... for sure ...

pay once.. remove.. replant ...

personally i would treat the stump so the roots die.. and leave it there ... and avoid the cost of grinding ...

do use someone with insurance... since you have one of those LP bombs sitting near it ...

ken

ps: i wish those were real prices ....

Bill:

-- Please let us know how this all turns out. :-) --

We decided that when the time comes to work on the tree, we will have the whole tree removed. We will get some quotes and advice on the best time for this. It will probably be before winter.

Ken: -- just be done with it all ... plant a bunch to replace it.. --

The area will look bare. I don' t know how long one should wait before planting another oak tree. Maybe we'll choose a different type of tree after getting some advice. And yes, we expect it to be costly. There's also a large "bull pine" that has about 90% dead needles so we might have that one removed too.

Thanks everyone.

Sad day.

Black oak RIP :-(

Thanks for the update.

Sad day for sure but can be considered a new beginning too. When I worked in the woods, I didn't feel too bad about removing damaged trees. It is a shame extended drought would cause that but I too would consider that I was making room for the next generation of growth. Any thought as to which tree you'll be replacing this with? I wouldn't be afraid to go with oak again but there may be better choices.

Have the drought conditions improved any?

We haven't decided on a replacement. Will think about it for a while. I don't know if drought was an issue as the oaks around here seem to thrive without much water at all. But maybe it was weakened by drought or something else and perhaps that made it susceptible to disease. The drought was declared to be over after a very rainy winter that ; the snow pack is at 115-120%!