Making Trident maple leaves smaller?

[Jhervi]

Hi yall,

I have a trident maple(1-2 years old), living in zone 9b

I noticed my trident maple, that I've had for three weeks now, has a few leaves that are much larger than the rest. These leaves actually came like this from the nursery I bought it from. Is it okay to snip them or will this affect the growth/ overall health of the tree? Or should I just leave them and let them fall off during the next season? I know that defoliating takes energy from the tree so I wanted to ask the experts what they think before attempting anything.

Side note, how do you keep the leaves small?

 

[Forsoothe!]

How many trees do ya got? What is your experience level? If you are new to bonsai then you should prove you can keep this critter alive for some period of time before you attempt sophisticated management steps. If this is a new tree it should live in your care for some time to prove it can before you do anything to it. There's nothing like having a tree take a dive after you do something to a new (in your possession) tree. Then you will always question whether the tree was healthy when you bought and would have died anyway without you doing anything good or bad. It's question that you can never answer and that will bug you for a long time.

 

[Shibui]

Leaves are food factories. Removing leaves will always affect the growth rate.
There seems to be a persistent myth that defoliating will result in smaller leaves but that is not correct. Growth will slow but new leaves are usually just as big as before.
The path to smaller leaves is long term. Ramification is the key. Leaves are like solar panels. Any given tree needs a certain area of leaf to collect the energy required. It can be from 2 really large leaves, 10 slightly smaller or 50 really small leaves all adding up to the same area to harvest sunlight. If the tree is small and only has 3 branches it can only have a few leaves and they need to be larger. When it has branches with lots of smaller twigs it will also have lots more leaves and each will naturally be far smaller.

The choice for this tree is between growth and development or smaller leaves. If you are happy with the little trunk and few branches you can cut off the largest leaves whenever they appear. Your tree has enough smaller leaves to remain reasonably healthy. I would also be trimming the longer shoots at the same time to maintain shape. Both those actions will reduce growth and development.

If you would like to thicken the trunk or increase the size of this bonsai you should try to overlook larger leaves and long shoots because those will be driving increase in size and health.

 

[Brian Van Fleet]

Yep...the more leaves it has, the smaller they will be. Don’t worry about leaf size yet.

Build a bonsai from the bottom-up. Go read about these topics and in this order:
1. Establish a good, radial root system which will become the nebari.
2. Build a trunk, which means letting it grow, in a controlled manner.
3. Add primary branches, and shape them.
4. Develop ramification, which will reduce leaf size.

Here is a thread that shows these steps over a 12-year period on this tree. The leaf size is reducing during the course of development.

 

[sorce]

That way...

You should never have to "try" to reduce leaf size or keep them small.

Slight measures may be taken before a show, to have them more uniform, but that should be the only "try".

Sorce

 

[Forsoothe!]

Actually, the leaves can be reduced greatly by defoliating, but that's a separate procedure that doesn't dovetail with taking off a leaf or two. The leaves can be reduced to almost ridiculous levels, -too close to each other for the health of the tree. But, that's another whole discussion.

 

[Smoke]

Actually, the leaves can be reduced greatly by defoliating, but that's a separate procedure that doesn't dovetail with taking off a leaf or two. The leaves can be reduced to almost ridiculous levels, -too close to each other for the health of the tree. But, that's another whole discussion.

Can you post up some pictures of this procedure you talk of. I would love to have leaves at ridiculous levels. Thanks.

 

[Paulpash]

Ramification & leaf size is primarily maths: genetics + culture.

Ground grown tree. Massive root mass. Access to high levels of moisture, nutrients and energy due to huge leaf mass = very large leaves and internodes.

Tree in development. Finite root mass / 50 buds = large individual leaf area.

Tree in refinement. Finite root mass / 200 buds = individual leaf area reduced by a factor of 4.

Genetics will also play a role in reducing leaf size (eg internode length, "standard" leaf size for that species).

Here is a Chinese Elm shohin that has good ramification (note the leaf size, 2mm) juxtaposed against a genetically identical branch that I took a cutting from and is now 12ft tall growing in the garden. They are essentially the same except one has had bonsai techniques consistently applied to it for many years.

Chinese Elm with restricted root mass but high volume of buds and short internodes.


A cutting of the previous bonsai grown in the garden, now over 12ft tall.


Comparison of internode & leaf sizes of both material side by side but cultivated with diametrically opposite goals in mind. The large leaved cutting is directly on top of the bonsai beneath.


You can see the obvious difference here but it's worth noting that I could never achieve the results I have got with the shohin Elm here if I were to apply identical methods but say with a horse chestnut or Ash. Genetics will always play a role in your success (or failure) to reduce leaf size. Defoliation has little effect if the tree's overall energy levels are still distributed across limited numbers of buds.

 

[Forsoothe!]

I'd only pick one little bone with you @Paulpash. Defoliation in mid-June (for me) forces a tree to grow a new canopy from sources recently depleted by growing the spring canopy. That alone would cause the leaves to be smaller, but adding the second half of the process of removing the primary tips on all twigs causes the tree to activate tertiary buds so there will be more than the original number of buds matured and inflated. So, the math is: fewer resources ÷ more buds not fully mature = smaller leaves. I do this the third week of June which allows the buds in the axils to be as mature as possible and still allow enough time for the tree to grow & mature a new set of buds for the next spring. Doing it too late in the season is asking for a silent spring. Too early is asking for a silent summer. Certain un-named western European detractors of this process claim that this process is very taxing on the tree's strength and weakens the tree. That's exactly the point. That's exactly how and why it works and is the price you pay. It's also why it should not be done habitually, or every year, or often. You do it knowing the price the tree pays, and don't take it to the point of excess. Death is the reward of those who overuse it.

It should be noted that the hedge trimming method also produces smaller leaves, especially on JM, but others, too. Hedge trimming removes all the outer, terminal, primary leaves which are the biggest leaves on JM and the inner leaves are all a lot smaller anyway. The new leaves will be smaller than the primary leaves they replace and the inner leaves will have parked and essentially stopped growing, so you get a very similar final product sans the greater stress. Six of one, half dozen of the other. The complete defoliation does reduce the size of the tree more than the hedge trimming method. Those who grow gargantuan bonsai favor the latter process. It might be pointed out that you get more money for giant bonsai than for hobby-sized trees. That may have something to do with selection of process. I'm not saying that all Huns are greedy or rich, but money talks and some people listen more closely than others.

 

[Smoke]

I was hoping for the pictures of the process and a tree that you have manicured down to tiny leaves, but talk is good I suppose.....

 

[Forsoothe!]

This tree has been in process for maybe 5 years after field growing for maybe 5 years...

You can see below (even with distracting shadows in background) the twigginess I attribute to editing the primaries 04/13/20


Then fully leafed-out today...

The lower branch is typical of the small leaves of the interior of the tree. I will be editing for clouds tomorrow.

A closer view of the top of the canopy...