We collected this very large Water-elm in 2018. The trunk base is 4″, and the upper trunk chop is at 29″. Last year it grew out strong, and I was able to wire the basic branch design. By the end of the growing season, the tapering transition at the upper trunk chop had thickened to roughly a third of the thickness of the trunk at the chop. I was able to achieve this despite directionally pruning the leader twice, in order to ensure continuity of the tapering.

Today’s goal is to carve down both the upper and lower trunk chops. If you grow very large bonsai, you will inevitably have to perform this task. It may seem a bit daunting the first time you do it, but you’ll be surprised at how quickly and how well it goes.

Here’s a closer look at the upper chop. You can see how well the leader thickened. I’ll continue this process during the growing season. My goal will be to double the thickness of the base of the leader.
My first task was to directionally prune the leader. As you’re building the apex of your tree, you’ll perform this task multiple times. The goal is to achieve movement and taper. Can you see three directional changes in my leader?
Here’s a closer look at my carving challenge. Notice here a key to my ultimate success in carving down this chop and making the whole thing both look right and work horticurturally: the branch growing below the leader on the opposite side of the tree.

Every trunk chop you ever make is going to create dead wood; it’s just unavoidable. But that’s all right, because the tree will produce callus tissue to heal the wound and, to one degree or another, seal off the live wood from the dead wood. With that said, it sometimes happens that the entire side of a tree will die due to a chop that is not followed by buds around the perimeter of the trunk. In this case, I have a branch perfectly positioned for what I’m about to do.

I used a root/trunk splitter to begin this work, followed by my knob cutter to bite away the bulk of the wood. You can easily see here both the living wood and the dead wood I’ll have to manage in the years to come. But that low branch will make all the difference, and sooner rather than later.

The treatment of choice for this chop, later on this season, will be lime sulfur followed by PC Petrifier. But that’s not for now. I need the living sapwood you see to actually dry out before hitting it with lime sulfur. In the meantime, I’ll just seal up the chop to protect it.

The chop is sealed with Kiyonal, my preferred product. Some of you may prefer the putty type, or another product altogether. As long as it works for you, that’s what you should use.
Here’s a shot of where we are at this point. Compare this photo with the first one, and you can see how much progress I’ve made in creating trunk taper at the apex of this Water-elm. Carving works wonders!
Here’ s my next carving chore. Notice in this case, just as with the first, I have a branch growing at the base of the chop. Once again, I couldn’t have asked for a better response from the tree.
Same technique as before, knob cutters to bite away the wood I didn’t need, then I used hand carving tools to smooth everything out. And lastly Kiyonal to seal it.
I did a little more strategic pruning, and that’s it for today! Doesn’t the trunk look much better now? It tapers nicely from base to apex, and the trunk movement is outstanding. Also, with the trunk chops carved down I can expect to create a very natural appearance as this tree develops.

I’ll post an update later in the season. This tree will be ready for a bonsai pot in Spring 2021.

Let me know if you found this helpful.