All you can do is carefully remove the split portion and wait and see how well the tree is able to respond to this very bad injury. No tree paint, no orange shellac is going to do one thing for that tree. In fact, that wound will always be there, even if the tree is somehow able to compartmentalize that wound. Tree will continue to grow but very likely, a rot pocket will form in the trunk there. Please do not fall prey to charlatans selling snake oil-type products. The tree either can or cannot deal with this, but no human intervention is going to make a difference.

I have exactly the same situation with a Cotinus obovatus. I have an arborist coming to look at it and I suspect that it will come down to what Ken suggests: do I want to look at it? With the Cotinus, plan b is not to plant another but to cut it off at the base and start again. So frustrating.

@Wisconsitom, @Ken, & @Sara - Thank you for your input. I have a bit of travel coming up so I will monitor it over the next few weeks and send an update. It is good to know there isn't any immediate danger, at least as much as anyone can tell.

@Ken - no attempt to rope it up... there is a bird feeder that is visible under the canopy in pic 2 and something that looks orange-ish within it near the top that I think is a leaf or maybe a frond from the nearby palm.

@Sara - if you could let me know how much your arborist visit cost and if you do go with plan B, any pics would be appreciated.

CH she is $90/hour and she is my consulting arborist so we have an appt scheduled for her to look at a whole bunch of trees and help with planning (many are small and we are working on shape and structural pruning). She has a one hour minimum; she's probably going to be here for 2. This tree will probably take about 10 minutes, is my guess. I'll report back!

It looks like it should have been subordinately pruned when it was young because this is considered a co-dominant leader. Follow Tom's suggestions and maybe cover it with plasitc/duct tape. An arborist is a good idea as well if you can afford it. To clarify, I have re-attached branches on lilac, flowering dogwood, and hibiscus rosa-sinesis with scotch tape and zip ties.

Tom's suggestion is right on.

Logan, the only thing you have clarified is your ignorance. Scotch tape and zip ties?!! Ya think that's gonna work long time, or at all?

Miketann, I have seen it work and can show pictures.

What about a complete patch using the bark from the broken off piece , cutting to expose cambium on the existing stem and staple into place. I realize this isn't the best time of year but the location is about as good as it could be. Just wondering because I have read about such but have never tried it myself.

Wayne's suggestion may be worth trying.

Scotch tape and zip ties....now I am going to have to remember that. Maybe I will try wite-out and paper clips!

white out and paper clips will not work LOL

I have to agree with Ken, albeit with slight modification:

i would have it removed ... and plant a new tree ... on personal
experience ... i would rather spend the next 10 years.. watching a new
one grow.. rather than stressing on HOW SOON it will die ...

I think it has great possibility of survival, this often happens to neglected freeman maples planted around here. They break off, sometimes splitting down the trunk. Never seen one die from this. Chinese pistache may be different. I am familiar with this tree, but have no personal experience. I think it looks too similar to rhus lanceolata (which is a nice shrub/tree).

I will monitor it over the next few weeks and send an update.

==>>> nothing will change in weeks ... we are talking tree time ... 5.. 10.. 20 years ...

odds of it dying because of this.. are low to nil ... othe3r things may attack over the decades.. bugs.. disease.. rot ... etc ... but again.. nothing will happen in weeks ...

in my world.. 90 bucks is what i would pay for the replacement.. not really to get an opinion about this thing .... of course that leaves out removal ...

personally.. on my 5 acres.. if this were out back.. i could watch what happens for ever ... if it were somewhere where i would be forced to look at it.. day after day.. after day ... it would be gone.. fast ...

the flip side of that coin is ... obtaining knowledge ... and watching this thing for 5 years or so ... would give you a lot of new learning ...

it would be a whole other ball of wax.. if it was a threat to anything.. like you or the house.. etc ... but this little thing isnt doing that to anything... as far as i can tell ...

ken

Logan, once that split dries, nothing can save it. It was weak before and any attempt to save it will result in a weaker bond that will eventually fail anyway. Why save it?

Yes, show some pics. Should be interesting.

I'd dig it up and be done with it. Lesson learned. Don't let co-dominate leaders develop. I call a secondary leader a 'Pretender to the Throne'.

Mike is exactly right. Don't let them develop to begin with. Too late for this tree (and my C. obvovatus) but a real lesson for me going forward. This is the reason that I spend so much time with my arborist on my small trees. Subordinating those problem branches early makes for a much more structurally sound tree later on.

Sara is right. As I'm always joking, it's a shame that public schools these days are so busy cramming kids full of rote learning to get them pass standardized tests that they can't take about 3 days of instruction at some point on "basic horticulture". You see SO many ill-pruned trees if you are looking for them. People need to learn to keep an eye on newly planted trees for the first couple years, and that an ounce of prevention in this case, is a ton of cure down the road! Literally - if, as in my case, a snow storm splits a 60' tall Juniperus that was allowed to develop a forked trunk. (What's really ludicrous is that you see badly pruned specimens in public gardens, but that's a whole other matter.)

It really is best not to let co-dominant leaders grow. As I said, everyone that owns a tree or plans on owning one should know subordinate pruning. While it may seem a bit absurd, it would be beneficial.