Timber's Cork Bark Oak

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Picked up this Cork Bark Oak about a week ago - figured why not share some baseline pics.

Picture below is after some initial trimming and lower-branch wiring to get a better feel for the trunk line.

CBO Front 1.jpg

The tree is in great condition, soil is a mix of substrate/organic and drains well. Will make a decision on a Spring soil change or repot sometime in the winter, but will almost certainly leave it in a deep growing container. I'll be aiming for maximum growth over the next 4-5 years mainly to close up a chop.

I'm not sure when it was chopped, but it's rolling over nicely and the wood underneath was hardened and with evident rot. Leader is positioned nicely from the front of the tree. In the picture below, the right side branch will remain on the tree to help close the wound for the time being.

CBO Chop.jpg

Below picture is after trimming and wiring the rest of the tree. The two upper-left most branches on chop junction are remaining for now to fatten the upper trunk, but I also quite like the lower one after raising it by ~1".

Left the branches long to encourage some branch thickening next season, and focused on creating movement near the trunk. Right smack in the middle of the tree is a wound from a removed branch. Maybe this heals over nice, maybe it becomes an interesting feature down the line.

CBO Front.jpg

There is more to the tree above that - unimportant to long-term design, and will largely grow free to fatten up the top.

Lowest left branch should be lower, but prefer to solve with a cutback in a season or two and have wired a branch as its eventual successor.

The soil and subsequent root line is still up in the air - something I'll think more about should I decide to change the soil mix this Spring. Hard to make a call on soil line without seeing what's under the hood.

I sketched out a scale design for the tree to get a better sense of how it should/could be down the road. From the normal bark line at the bottom of the tree, ignoring/burying exposed roots, the trunk is ~16" to the chop and tapers by ~1". In the drawing, I'm aiming for another 8" of trunk from the top of the chop. In the picture above, that's roughly the top of the picture.

Purple tip is a good idea about where I'd like the trunk to end up, about 3 chops and 12 years from now. :)

Redline would be a nice place for a bud to come through over the next few seasons. If not, I have some options to fill that space from the growth on the right side of the chop wound.

Trunk Plan Scale.jpg
 

Housguy

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A man with a plan, looks good! One question, was the base wired? Interesting how the corking is flaring out. Is part of your plan burying it to the flare one day?
 
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A man with a plan, looks good! One question, was the base wired? Interesting how the corking is flaring out. Is part of your plan burying it to the flare one day?
It may have been. There is some tie-down wire on the surface that may have been moved. Will take a closer look, but wouldn't surprise me.

Burying to that level is what's mocked up in the drawing. Depends a bit on what else is under the soil and I suppose my confidence in developing new roots near the base of the cork.
 

Potawatomi13

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Base problem is roots wrapped about base of trunk. Should have been unwrapped while small and thin. Huge fault in beauty of trunk above. Personally would remove CAREFULLY in small pieces and not damage bark above;).
 

Bonsai Nut

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Your biggest challenge with this material is that it pushes a ton of bark (duh). I know that sounds pretty basic, but you have to look at your current upper trunk, and assume that in a couple of years it will be as thick as the lower trunk. That would probably leave you with a tree that is too tall, and too uniform. I would consider reducing your upper trunk to 4-5" above the old pruning scar. Angle your cut 45 degrees, with the cut facing the rear of the tree. Do this when the tree is actively growing in the early spring or early fall and you will get a plethora of buds. You have to constantly work to constrain the apex, and develop ramification without letting the branches run and get too thick.

This is the one species of tree where I find myself trying to restrain trunk development, instead of encourage it.

FWIW cork trees that are used for commercial cork production are harvested every nine years.
 
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BrianBay9

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These trees don't bark up below the soil line, and I believe that's the issue at the base. It was originally planted lower in a pot. I'm told once exposed it will bark up like the rest of the trunk, so I'd anticipate it getting better over time.
 
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Your biggest challenge with this material is that it pushes a ton of bark (duh). I know that sounds pretty basic, but you have to look at your current upper trunk, and assume that in a couple of years it will be as thick as the lower trunk. That would probably leave you with a tree that is too tall, and too uniform. I would consider reducing your upper trunk to 4-5" above the old pruning scar. Angle your cut 45 degrees, with the cut facing the rear of the tree. Do this when the tree is actively growing in the early spring or early fall and you will get a plethora of buds. You have to constantly work to constrain the apex, and develop ramification without letting the branches run and get too thick.

This is the one species of tree where I find myself trying to restrain trunk development, instead of encourage it.

FWIW cork trees that are used for commercial cork production are harvested every nine years.
Thanks for this detail. I assume the top thickens faster than the base, relative to proportion, as well.

Will make that cut in the spring or fall next year. The trunk above that cut has nice movement and taper.

I have 3-4 air-layers I'm planning for the Spring and could add this to the list.
 
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Base problem is roots wrapped about base of trunk. Should have been unwrapped while small and thin. Huge fault in beauty of trunk above. Personally would remove CAREFULLY in small pieces and not damage bark above;).
Yeah at present the roots below the bark line are very unattractive. I'm drawn to old trees with big flaws. 😅

Easy solution would be to raise the soil and ignore it. I almost certainly wont be doing that.

I'm more inclined to leave it exposed for awhile and see if any bark develops, hoping what Brian notes above comes to pass.

Will look to address any easy root issues during next soil event, others over time.
 
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Little update on the CBO. Really strong growth this spring.

Elected against a repot this spring given it was my first Spring with this tree.

Really wanted to focus on this trees chop wound this year. The top of the wound was rolling over, but progress on the bottom was hard to gauge since it was buried under hardened wood and cork.

IMG_1047.JPGIMG_1048.JPG

I used a dremel to grind down the stump, and a sharp knife to expose cambium.

The wound was covered with cut paste, and I applied fresh hardener to the wood.

IMG_1062.JPG

There's a very healthy branch at the bottom of the chop which should help close this wound over the next 30 or so years.

Next up for this is a top chop, perhaps in early fall. The top of the tree is actually quite nice, so it may turn into an air-layering project.
 
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I've been wiring new shoots from the trunk to eventually replace some of the straight existing branches.

This tree has been growing very strong this year. On strong growth branches, the wire lasts only ~3-4 weeks before I have to remove.

Also applied a container airlayer near where BN suggested on June 6th. I airlayered because the top has better movement than the actual tree - despite not having space for it. 🤣

IMG-1173.jpg

Had a small hand slip when I was cutting the airlayer and nicked off a potential leader I was looking to save.
About three weeks later, a whole host of buds popped right below the bottom of the container.

IMG-1172.jpg

About three weeks after that, really strong growth above/below the layer:

IMG-1223.jpg

Have no clue if the layer is taking or not, but will be checking in a non-invasive way.

This is a fun tree to work with up-top, but really needs a lot of work at the base.
 
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Finally repotted this CBO after ~2.5 years - reducing thick roots from the bottom.

Was also able to get a better view of the wrapped root at the base, and repotted such that I can work on starting to remove that.

There was still a large amount of sludge/field-soil at the base of the tree, all of which was removed.

repot 2023 1.jpeg repot 2023 2.jpeg
 
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