The marks should go away with time as long as the tree is healthy, depending on how deep they are it could take months

I have a japanese maple that arrived late winter 3 years ago. It was kept in a dark celler until middle spring but was wired to keep the trunk straight. The wire was removed early summer. The wire marks are still there.
If anyone knows how to rid the trees of these marks it would be appreciated.
Layering or a chop will not do it.

Paul

When it really matures (a couple of yrs isn't enough) and gets proper bark, they'll disappear.

Thanks Lucy.
Your right the bark does look immature.
Paul

Hello,
I grow birch, maple, oak, and ficus as bonsai. I found a way to remove the wire marks. I use a very fine grit sandpaper. Scrub the marked area lightly once a week. Over time this makes the bark swell and roughen up in the area being lightly sanded. After a while it will look like a natural patch of mature bark.