How do you treat cambium damage?

Not girdling, just a scraped off area from where a tree landed on it. I have it on good information to leave a trunk injury on a two or three year sapling like this alone, but wondered if there were other opinions. Or maybe the response depends on the type of tree?

I've had something like that happen on a tree that I wanted to recover quickly.

You can remove the damaged pieces of bark and wood, it can help the tree heal over quicker, since the new growth can cover the wound quicker and easier.

Hope that helps! What type of tree is it?

It's a seaberry. In my experience they're pretty resilient, but I'm very fond of that specimen.

Thanks for the tip...that makes sense, because the same thing sometime applies with humans. Sometimes it's better to bandage a flap of hanging flesh over a cut, sometimes better to cut it off because it's mostly severed and traps dirt. I see no one here holds truck with sealing wounds with tar or wax or whatever; reading about grafting I found those practices mostly frowned-on.