AusBonsai

I'm a beginner and need advice with this Elm. I'm going to grow it in the ground and was thinking of wiring a new leader (shown in red). Would this be OK?

Why there? start a fraction higher with a leader already present and which will omit more scars (bigger) than needed.....does that help, hard to see with your present image.

cheers Anthony

anthonyW wrote:Why there?

I chose that one because it's lower down. If I choose the leader higher up as you suggested I'm concerned that the tree will be too tall. The base is 20mm. What do you think?

Of course wiring up a new leader would be Ok if that fits in with your overall plan.
Is the aim to have a straight trunk or a twisted, bendy tree? Current angle of that branch looks pretty good to me, especially if you lean the trunk a little to the right.
Personally, I don't worry too much about the shape of easy budding trees before they go into the ground. By the time it has grown a bit you won't recognise it and your original plans will probably have to be changed. Just plant it, let it grow and then work with whatever turns up later.

shibui wrote: Is the aim to have a straight trunk or a twisted, bendy tree?

Bendy

Then don't bother wiring that branch. It will give you a change of angle when the rest off the trunk is cut off some day.
I'm assuming that first branch will become the continuation of the trunk at some stage but many changes happen while a tree is growing and thickening in the ground. By the time it has reached desired thickness it won't look anything like it currently does.

Bendy

A little bit bendy or extremely twisted?
If you'd like the first bend to be even more extreme then maybe wire it out wider to give even greater change of direction.