Trident maple development question

This is one of the first trees I bought as a seedling off the internet 7 years ago. All I knew to do at the time was plant it in the ground. Sixteen months ago I chopped it and potted it in his box. It already needs repotting but can wait until spring. The trunk diameter at the soil line is 3 inches. I now see how easily it would be to create a 1-2-3 tree with a Trident because they bud at just the right places. However, I like maples with multiple ascending trunks and slightly rising then drooping branch lines. With wire, you can see that the primary branch is following this pattern

I'm planning on letting the second section of the trunk thicken one more year before chopping in spring 2017. I hope it is obvious where I intend the second chop. At this third trunk section I hope to spur multiple trunks to form the crown of the tree. Walter Pall has stated that all (or most all I'm not sure) broadleaf trees look best as informal brooms. That is what I would like for this tree.

I feel like the tree is at a fairly critical stage as far as the ultimate design is concerned. Decisions made now will have big implications for the future development. Any sage advice that could be offered now would be appreciated. I'm really wondering whether better taper be achieved if I chop the second section next spring or should I wait until 2017? Also, I really have no idea how to create multiple trunks to form the crown. My plan was to watch it grow and pick and chose what to let grow and what to cut.

For the multiple trunk (main branches) look I think you are better to chop sooner than later since you will want the multiple branches to be similar in size rather than much smaller than the main trunk line.

If you look at the second trunk and how parallel it is right now the chance of the section between the main trunk and the new leader/right hand branch fattening up much with another year's growth is unlikely in my view, as the majority of growth will be directed upward and onward. So I would chop next spring as the branches that you leave will cause just as much, if not more, localised growth and taper, as it is branches that help fatten trunks and give taper, not straight up growth. This may contradict conventional wisdom in some respects, but I've found it to be true in my experience, as something that's pushing all its energy into growing upward isn't going to be pushing much energy into growing outward. (This is why we all start getting fatter when we stop growing upward - its not really the donuts!).

JT - MKBonsai

Thank you Marty and JT for your detailed responses. They make perfect sense to me. I plan on chopping next spring.

Thanks again,
Steve

Have you tried to draw a picture of what you want the tree to do in the future? Even if you draw in imagined branches that are not there yet it is very useful to have that image as a guide.

Waiting for the tree to reveal itself will be counterproductive with a trident, as it's best growing traits are revealed when you are working it hard according to a plan.

You have a long straight and very imposing trunk that has little movement. If you want a formal upright with branches coming off that as you go up then your current approach may just do it. But I think that is the wrong design for a trident.

May I suggest you exploit what you have and aim to build a very nice broom style tree?

I would do a v-cut between the 2 branches on the right side that have wire. Make it deep enough so that when it heals over the scar will not cause a bulge - tridents form huge callouses.

Then I'd just spend the next few years building a ramified canopy.

Off that trunk you'd have an impressive summer image within a year, and within 3 years you'd have a good winter image, too.

I'd certainly cut away everything above the wire as it is straight, boring and sufficiently thick that you need to be careful how you reduce the scar that will develop when it goes. I suspect that it is not thickening the trunk in a useful manner right now, as the tendency is for the upper branch to thicken to match the lower trunk, and while the lower trunk is going to thicken in the process you will find that the upper thickens faster. In effect you'd have a very thick very long trunk if you just left this to grow. Chop it now, and chop it hard.

Here is a quote from one of the greats: "Here a few of my maples. I think broom form(informal broom form) is THE appropriate form for maples.
Trident, Acer burgerianum, Japanese maple, Acer palmatum" - Walter Pall

Here's the post - https://ibonsaiclub.forumotion.com/t2285-clean-sweep-show-us-your-brooms

I'd also look to getting it into a training pot soon, as the chances are that you will achieve better ramification and smaller internodes if you restrict the roots a bit.

With tridents the simplest approach seems to be that you let it leaf out in the spring, and as soon as the leaves harden off you cut back to the first pair. It will then typically produce 2 further branches and pairs of leaves along each branch. If you are not feeding it too much when you make this first cut the growth of the first internode should not be too long and you may be able to do a second cut in mid-summer where you reduce it to the first pair of leaves on each of the branches that grew from the initial pair. Then leave it for the season as it needs to make food.

I would feed it like mad after mid season as it is healing and storing energy for winter, and you'd be doing a similar job the next year.

In the winter you will have a staggering number of branches to choose from, and they will then be able to be placed within your plan.

BTW I really like your trunk, and I think you have the makings of a super tree there.

Thank you Brendan for your response.  I agree that informal upright broom is the best way to go for this tree.  I'll cut it where you suggest tomorrow.  For a broom I'm thinking I need to direct the lowest short branch on the right more upward.  Ill wire it up some as well.  Your idea of a smaller training pot is also spot on.  I'll root prune and repot next spring.  After 5 years of ground growing and a trunk chop, I'm now learning the next stages of development - branch positions and crown formation.  This seems harder to me but much more fun.

I'll keep this post updated and thanks again for you response. 
Steve

PS - I'll give sketching a shot.

OK, time to post the pics of what you did?

All I did was cut the leader and wire another one. Next summer I want to choose 3 or 4 branches off the new leader to start forming the crown. That is the plan anyway

Thanks for your help

I would let the leader run for a year to thicken and help close the lower wounds and then cut back. I have let the leader run, but back the first branch, let it run, and repeat for 3 years and now have nice taper and near closure of a huge wound. This past year I keep the apex in check and allowed the lower branches to run so they would thicken. I just did a little more branch selection and will develop ramification over the next 2 - 4 years.

That looks like the perfect cut. I agree with Marty about the cut and grow process. You will see the leader can put on easily 6 foot in a season, and that will give you plenty to get the taper in for the top. It will also help with creating opportunities for back budding and side branches.

Looks like a really nice tree to me!

Did you practice the trunk chop chop the stone guy in the background?

No, it came off without my help.

It's a great improvement to the maple - just what wa needed in my view - a very nice basis for further development - so please update your post as things develop next year. You've a nice tree there!

JT - MKBonsai

Thank you and I will and thanks for your guidance!

Steve

Just a quick update.  I repotted into a training pot last Spring with 100% Mule Mix and a little pine bark thrown on top to keep it from drying out there.  I've cut it back to the imagined silhouette twice this summer so it wouldn't shade other trees on my limited bench space.  My primary branch is starting to ramify.  I chose my second, back, and third branches.  I'm into my 8th year in bonsai and have basically been growing trunks for 5 years.  Growing branches, ramification, and creating a crown are all unexplored territory for me.

From the picture, it looks like the tree needs a smoother transition from the primary branch, upward.  I will probably let the leader grow unchecked next summer to thicken the upper part of the truck.  I will then need to start creating a crown.  To the first branch is 10 inches.  I imagine the finished height to be about 20 inches.  Feel free to comment.

Looking good. I have found that you can start to develop some of the crown while letting the leader run by pruning the first couple of branches on the leader to develop the crown, stripping off most of the branches and leaves, and leaving about a foot (30 cm) of the leaves at the top of the leader. The leader will continue to run and thicken, but the long blank spot will not weaken the small branches at its base so much that they don't grow and ramify.

I have been told and have some limited experience that trident maple branches thicken best by unrestrained growth of the tips. Cutting the tip and creating lots of side branches is not that productive even if the total amount of leaves is more with the side branches.