Japanese maple thread

[NBPCA]

Hi all,
Here is a Japanese Maple (Acer palmatum) that has been a part of the national Bonsai and Penjing Collection since it opened in September 2008.

1 Japanese Maple Sept 2008.JPG

It had been an established bonsai for many years before the current owner came into possession of it, and it had won the popular vote at a number of Canberra Bonsai Society shows in the 1990s and early 2000s.
The owner agreed to allow us, with his active participation, to gradually improve the structure of the tree while still keeping it on show at the NBPCA.
The tree had always been styled from a certain angle to be the front but over the years the root structure had expanded on a different plane to the front of the tree and it now looked a bit funny; so that was a long term problem that had to solved. In effect the tree needed to be turned about 20 degrees to one side to show off the roots to the best advantage. This however would of course turn the front towards the side so we needed to embark firstly on a campaign to encourage the tree to bud back and give us some new branches to work with.
The first thing you do to a Japanese maple to encourage it to back bud is to follow assiduously the correct trimming regime in early spring. As the leaves first come you let the first pair of leaves form then you pinch out the emerging new growth from between the first set of leaves. You should do this as soon as you can as it stops the elongation of the internode.
If you do this correctly you will instantly get a much fuller tree with more compact silhouette.

2 Japanese Maple Thread 12th Dec 2008.JPG

The next thing you can do to encourage the tree to bud back (remember this is while the tree is still on display) is to defoliate the tree. This was done in December 2008 on a very wet day.

3 Japanese Maple Trimming 12-12-2008.JPG

4 Japanese Maple Defoliated1 - FK - 12-12-2008.JPG

We then also did a light trim back of some branches and removed a portion of the apex. The apex over the years had been allowed to elongate and move too much to the right. This clashed with the overall movement and feeling of the tree; so we resolved to progressively shorten the apex and change its feel and direction.

5 Japanese Maple Defoliated10 - FK - 12-12-2008.JPG

In autumn 2009 we got a fabulous display of autumn colour.

6 Japanese Maple Studio - FK - 14-5-2009.jpg

Grant Bowie,
Curator NBPCA

[bodhidharma]

A lovely tree Grant. In thinking back we dont see a lot of good developed Japanese Maples Displayed here. Hopefully this might bring them out of the wood work.

[Aussie_Bonsai]

Great tree. I hope i can turn my young Japanese maple seedlings into something like this oneday.

Ben

[NBPCA]

We got a good amount of back budding after the first year but we still had a bit of a hole on the lowest left branch that needed filling (if we were to eventually turn the tree 20 degrees to the right) so we came to a decision in December 2009 to....

7 Dec 2009.JPG

Defoliate again.

8 Defoliated Dec 2009.JPG

But leave undefoliated a small branch that had emerged at the back of the tree. We would allow this branch to elongate and thicken.

9 Showing new branch for thread grafting.JPG

And then do a thread graft.

10 Maple Long Branch - Feb 2010.JPG

Grant

[Scott Roxburgh]

I love this tree!

It will be great to get some good advice about how to get the best from our Japanese Maples. I am very interested to see how the great maples at the collection are treated.

I have two 60-70cm stock trees that I got from Robertson, currently getting used to the Canberra environment and building up strength for work this coming year. First up will be the removal of the large 'branches' from the field, then an intial wiring of the buds that come out. I am also interested in doing a few branch/root grafts so this thread is much appreciated.

[NBPCA]

The tree grew strongly throughout the rest of the year and once again gave us good autumn colour

12 early autumn 2010.JPG

13 Autumn 2010.jpg

We prepared to do the thread graft in Winter 2010.

14 Before Front -.JPG

15 Before RHS -.JPG

[NBPCA]

First we did a test drill in a portion of the apex that was going to be cut off.( We had decided to take the tree off display for the duration of this thread graft.). We then did a test thread with a portion of Japanese maple I had brought from home. We knew that the size of the buds were going to be an issue so we wanted the size of the hole to be firm as possible but still allow the new branch to be pushed through.

17 Practice Drill.JPG

18 Practice Thread.JPG

We thin drilled the hole in the lowest left hand branch where the new branch was to go

20 Drilling.JPG

21 Drilling.JPG

[NBPCA]

We then wired the new thread graft branch and bent it carefully to near its new location. We had kept flexing the branch over the previous months to keep it flexible and to make sure it would reach its new location.

19 Wiring thread.JPG

22 Bending thread.JPG

23 Bending thread.JPG

Then threaded the new branch carefully through the hole.

24 Threading.JPG

25 Threading.JPG

Once we were happy with its position we then secured the wire around the new host branch to hold the thread branch in position

25 Securing thread.JPG

[NBPCA]

We did not scrape any bark or cambium off but did insert some wedges to force contact between the new branch and its host. The buds of the Japanese maple are quite large compared to the Trident maple so therefore the hole was not a snug fit once the buds had passed through the hole.

30 Wedge.JPG

31 inserting Wedge.JPG

32 Wedge inserted.JPG

33 Another Wedge.JPG

34 Wedge inserted.JPG

35 Pruning Wedges neede a steady hand.JPG

The graft is then sealed with putty.

27 Sealing.JPG

28 Sealing.JPG

[NBPCA]

OK now; we had finished the thread grafting proceedure but we still had some unfinished business.

40 After threading completed.JPG

40aa Cutting top off.JPG

40a tidying up top cut.JPG

41 Pruning apex and strong top branches.JPG

42 Pruning.JPG

43 Pruning heavy top back branch.JPG

44 After top pruning completed.JPG

[NBPCA]

So after a very full and hectic day; what was the outcome.

We had done the thread in late winter to make sure the sap was not flowing and it appeared OK; however the tree bled fairly significantly for about a week so I did a light repot of the tree about 10 days later. This dried up the bleeding.
We also trimmed back a bit more of the tree all over to really give the thread branch a head start in spring.

How did it go? Great so far.

50 Front after defoliation dec 2010.JPG

Notice how well the tree has put out new buds at apex area

51 Side after defoliation.JPG

52 Back in leaf and about three weeks after defoliation.JPG

53 Notice callousing and thicker on out side.JPG

I have trimmed the tree back lightly yesterday and left the threaded portion untouched. It should elongate dramatically over the next few months and thicken considerably and join up/graft as expected.

Thats it for now; There are lots of other pics as well but I didn't want to over do it.

Grant

[Scott Roxburgh]

Great work guys, and very good pictures to help explain the process

Thanks

[Andrew Legg]

I want to echo Scott's comment. Thanks for the info guys, and it is thanks to people who record meticulously their procedures that we get real value from these forums! Well done! Oh, and nice tree. Very nice!

[Grant Bowie]

You are all welcome.

How many noticed the next thread graft being prepared? We will be using a new branch that popped out this year to make a new branch about 2/3rds up the tree on the left front side.

Grant

[Scott Roxburgh]

I went to see this tree today, It's looking great guys.

It was good to see it in person.

I also saw the Red pine...nice!