Not mine

Mine

Mine

Trying to root my thin trunk Ogon which just seems to grow this way w/o pruning

Does seem that lower branches build up mass around and supporting them, so limbing up early perhaps leads to a smoother, less bulky trunk. Look at the Longwood Gardens example that I posted that they left just about every limb.

That is a neat tree in your post.

Can you think of any other species where limbing up makes such a difference to the trunk?

I've read that leaving lower limbs in general leads to bigger bases. If you look at some trees, a large lower branch looks like it has a separate "mass" down along the trunk and going into the ground as a associated/supporting major root.