Removing an air layer

About a year and a half ago, I started an air layer on a Japanese maple (see “Air layering a Japanese maple“). I checked on the layer’s progress the following winter and found that the wound had produced callus but no roots. I reopened the wound to stimulate root growth and by spring a few roots had appeared (see “Japanese maple air layer – a check up“).

This past summer I noticed roots developing inside the layer bag. How did I know enough roots had grown to warrant removing the layer? Just below the bag the trunk had begun to die. Instead of waiting until late winter or early spring – good times to remove air layers – I separated the layer a few weeks ago. Here’s the basic process.

Japanese maple – December 2013

Trunk dieback below the layer

The layer bag

After removing the bag – the moss has turned green

After removing the bag I used bent-nose tweezers to carefully remove the sphagnum moss from between the roots. This process took a long time as the roots were all a-tangled.

After removing some of the moss

Most of the moss removed

Moss from the layer

I removed the layer without ceremony leaving behind a deciduous version of Charlie Brown’s Christmas tree.

After removing the layer

The apex

I wasn’t surprised to see that the trunk below the layer had completely died as the bark had begun to separate from the tree, but this was first time I’d seen a layer completely kill off the wood below.

The dead trunk

The next step was to pot the layer. I first removed some of the dead wood below the roots with large root cutters.

Removing dead wood

I next added some bonsai soil to the pot and set the tree in place. Normally I wire trees into place before adding soil around the roots, but for air layers, trees that have been bare-rooted and recently collected trees, I’ll usually add soil between the roots before securing the tree.

Adding soil between the roots

I used chopsticks to stabilize the trunk.

Chopstick holding the trunk in place

When using chopsticks to stabilize the tree, I try to line up the two sections as close to a straight line as possible.

Chopsticks front and back

These chopsticks help keep the tree from moving front to back. To keep the tree from moving from side to side, I used the wire in the pot to secure a branch on each side of the tree.

Using a branch for the tie-down

I used branches to secure the tree to the pot as the roots are too delicate to offer much stability at this point.

Layer freshly potted

Now that the layer is complete, I can think further on my plan for the tree’s future. The original plan was to lay the tree on its side and make yet another layer to create a multi-trunk bonsai, but I think I’ll wait a year or two before deciding what’s next.