Japanese Maples and Healing Large Wounds

I recently came across an interesting Momiji (Japanese Maple) project with nice subtle curves and slow elegant taper – great features for a raw stock Momiji.

Momiji Before Work

Now you may have noticed one or two major details about this tree… 1. It is in major need of a repotting which luckily when these photos were taken was the perfect time to embark on this operation and 2. How do we successfully get rid of that huge sacrifice branch? Stay tuned and you will find out!

Close Up – Bottom of Grow Box
Close up of Roots After Removing Box Side

Can you say roots? further evidence that this tree was in need of a repotting.

Raking Out the Top of the Rootmass

Typically we would start by raking out the bottom of the tree but in this case i wanted to begin by removing some of the weeds/moss and finding the nebari… Then onto the bottom. I use a single prong root hook to do this work and a 3 pronged root rake for the bottom.

Japanese Maple Planted on a Board – 3 Pronged Root rake in Front

After raking out the bottom of the root-mass slightly I found a pleasant surprise – this tree had been planted on a board by the previous grower. This makes my job a lot easier.

Then I went on to remove some unsightly larger surface roots on this tree…

Closeup of Roots We Remove

This root was emerging from underneath initially and then on a different plane than the rest of the nebari. When developing a good nebari on deciduous species we want to have all roots on the same plane or level. This is the way to develop a nice fused or “melted” nebari over time.

Unnecessary Root

This root is crossing over a root that we would like to keep – not good for the future nebari by any means.

Another Root I Removed

This root is crossing over another root that we would like to keep and growing inwards towards the trunk – this must be removed to develop a nice nebari in the future.

Closeup of Roots

Now we have the root ball after removal of most unsightly and downward growing roots. Note: I did not remove as much roots as I could have or in some cases should have… At the moment I am most focused on healing the wound left behind from removing that large sacrifice branch and a lot of energy in bonsai is stored in the roots – Happy roots=happy tree.

Growing Box – Prepped With Wire and Growing Medium

A second Note: Again, in the case of this tree I am most focused on healing that large wound we have been talking about. At this time there is no precedent set on developing ramification or shortening internodes. Larger particles and more pumice which both dry out quicker typically deliver more root growth which results in an overall stronger tree.

Momiji After Potting

Here is a photo of the tree after the repotting was finished and before making any judicious cuts.

Semi wedge cut

Here is a closeup of the cut that was made – the initial cut was made with a saw, then chisel and cleaned up with a sharp knife. This technique was brought to fame by the great Ebihara. He would typically do a wedge cut as seen below but i am experimenting with a more square cut to see if there is any advantage to this method of doing the cut. He also brought the nail and board technique of arranging and developing roots on deciduous tree to fame.

Ebihara Wedge Cut – Image Borrowed from https://bonsaitonight.com/

This puts us at an advantage in two ways – 1. We are using energy from two branches which means that come this spring there will be strong growth healing both sides of the cut 2. Doing this cut in two stages versus one also allows the tree to heal a smaller wound in 2 stages versus a large wound all at once which will result in a quicker closing cut.

Enter a caption

Make sure to apply a liberal amount of cut paste or would sealant after the cut is cleaned with a sharp blade. IMG_1834

And the “finished” product – for now that is.

I plan to make a medium sized tree but the growth will be kept long for now to aid in the healing the wound left behind by the sacrifice branch.

If you are enjoying the blog so far please subscribe to my posts to see more of this work in the future. 

You can also follow my work on various other social media – particularly Facebook and Instagram at this moment. 



7 thoughts on “Japanese Maples and Healing Large Wounds

  1. Hi, This is a really useful article. I am using the same technique on a ‘shishigashira’, how long did you / will you leave the notch cut branch on before removing it all together to complete the healing?
    Best wishes,


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s