Ficus defoliation experiment...

[Starfox]

OK so this has come from another thread with the general idea to see how defoliating a ficus, in this case microcarpa cuttings, will effect long term growth. For example will defoliation inhibit the growth or speed it up. Now there is plenty of reading on the webs that state a case for either and instead of citing one post or another I figure it is best to see what happens first hand. This will obviously be a long term project to see the best results but I will update the thread every now and then and hopefully don't kill the things in the process.

So to be clear I am starting off with two cuttings that were started at the same time and are of similar size and have now planted them out into larger nursery pots filled with a mix of potting mix and lava rock.
Both pots have had a handful of nutricote pellets chucked in and will get the same water and weekly/fortnightly liquid feed.

One cutting will be defoliated probably 3 times during a growing season and I will not cut any branches either.
The other will not be defoliated or cut at all.
The only caveat I will add to this is in Spring and Autumn we tend to get thrips so I will remove any affected growth on both plants when this occurs.




Both cuttings are at about 0.5 centimeters now and both will sit next to each other in the same spot.
Being mid season now I may not get another shot at defoliation this year but then again I might, I wont do it if I think there is not enough time.

 

[sparklemotion]

Thanks for posting this. I'm sure you'll get plenty of *ahem*feedback*ahem* about sample size and how this isn't really "scientific" but I think it will be interesting just to watch how these two trees respond over the next year or so (and beyond?).

Do you happen to have links to things that people have written on either side of this question? I'd like to read what smart people on "both sides" have to say, and develop a theory of my own that can be tested by this.

 

[Mellow Mullet]

It will be interesting to see what effects you observe. I have a larger ficus benjamina that I defoliate yearly (well to be fair I only started last year so I have only done it twice) to get smaller leaves and to make it easier to wire. The defoliation also seems to stimulate a lot of new growth.

John

 

[Clicio]

Thanks for posting, this will be very interesting to follow.
Isn't there a way to avoid the thrips before they get into the trees?

 

[Starfox]

Thanks for posting this. I'm sure you'll get plenty of *ahem*feedback*ahem* about sample size and how this isn't really "scientific" but I think it will be interesting just to watch how these two trees respond over the next year or so (and beyond?).

Do you happen to have links to things that people have written on either side of this question? I'd like to read what smart people on "both sides" have to say, and develop a theory of my own that can be tested by this.

You make a point about sample size, in fact I nearly mentioned that in my post so I'm going to root a bunch more cuttings now and add them to it next year, if I can get 5 more of each to add to it then that should be enough to see a pattern.
I only had 3 cuttings of the same size available and the other is throwing out syconia so I didn't want to add it.
For a backyard hobbyist it's about as scientific as it needs to be really without getting into the physics and chemistry of it which is beyond most but I guess any results can then be linked to what is going on chemically with the tree.
For this I'm not getting too carried away, measured trunk thickness should do the trick. These cuttings have to grow a few years anyway and it is not going to put me out much so why not.

I'll have to dig some links up but some of them would be on Adam Lavignes blog, he goes into detail in numerous posts with some of the science behind it, a podcarpus springs to mind. I think I googled something like "why defoliate ficus" I can check when I'm back on the other computer. There was also a thread on bonsai empire or 4me forum with some familiar posters poo pooing the idea using logic. And I know there are more but I don't believe I definitively read an answer one way or the other on the effects of defoliation on to speed up or slow down trunk building. I have a quieter week this week(lol obviously) so I'll see what I can dig up.

It will be interesting to see what effects you observe. I have a larger ficus benjamina that I defoliate yearly (well to be fair I only started last year so I have only done it twice) to get smaller leaves and to make it easier to wire. The defoliation also seems to stimulate a lot of new growth.

John

I think it is an interesting question, it came from a question in the other thread in a round about way so I figured there is no harm in having a look for myself and see.
I'll even try and add some benji cuttings in the next batch as I have one that needs a trim.

Thanks for posting, this will be very interesting to follow.
Isn't there a way to avoid the thrips before they get into the trees?

There probably is a preventative spray but I'm not sure what it would be called and contact sprays don't really do much. Maybe neem? I don't know on that.
To be honest I have learned to embrace them, when you see effected leaves just pluck them, it's like a partial defoliation and maybe lasts a month but it happens when everything is growing so it probably is good for the trees to have a little haircut. To be fair though I have not had a real bad infestation yet so my opinion is open to change when I do.

 

[sparklemotion]

You make a point about sample size, in fact I nearly mentioned that in my post so I'm going to root a bunch more cuttings now and add them to it next year, if I can get 5 more of each to add to it then that should be enough to see a pattern.
I only had 3 cuttings of the same size available and the other is throwing out syconia so I didn't want to add it.
For a backyard hobbyist it's about as scientific as it needs to be really without getting into the physics and chemistry of it which is beyond most but I guess any results can then be linked to what is going on chemically with the tree.
For this I'm not getting too carried away, measured trunk thickness should do the trick. These cuttings have to grow a few years anyway and it is not going to put me out much so why not.

I was hoping to head off a debate about the "value" of this experiment by reminding folks of that their is value even from small comparisons like this, especially when genetic variations are minimized (cuttings from the same parent).

As I have tried to understand horticultural science as it applies to bonsai, I personally have struggled with the contradiction of: more foliage means more growth, increased ramification makes more foliage (leaves), and the admonition not to use techniques to increase ramification (pruning/defoliating/pinching) while the building the trunk.

 

[amcoffeegirl]

Interesting experiment.

When defoliating I would also cut the growing tips- but perhaps that is a different experiment.

 

[coh]

The problem with drawing conclusions from a sample size this small (and you can't really go any smaller than 2) is, you might be getting a result for the wrong reason. The tree that you defoliate might grow a bigger trunk, for instance, but it might not be because of the defoliation - it might be that something you haven't accounted for is negatively impacting the other specimen. Then you go and apply what you think you've learned to your trees and you could actually be setting them back. If you add another variable like trimming shoots because of thrips, you further complicate things. I'd recommend using an insecticide rather than cutting.

Anyway, I defoliate my 2 willow leafs when I put them outside for the summer, because the old leaves have gotten ratty and removing them allows me to see the structure and make adjustments, wire, etc. There is always a strong surge of growth after the defoliation, but I don't know if it's stronger than what I would get if I left the leaves on.

Good luck with the project. Let us know what happens!

 

[choppychoppy]

Thanks for posting, this will be very interesting to follow.
Isn't there a way to avoid the thrips before they get into the trees?

Use a systemic in the soil mix.

 

[MrBeto]

It will be interesting to see what effects you observe. I have a larger ficus benjamina that I defoliate yearly (well to be fair I only started last year so I have only done it twice) to get smaller leaves and to make it easier to wire. The defoliation also seems to stimulate a lot of new growth.

John

Do you think this is the right time for ficus defoliation ? I have a ficus virens that I want to defoliate to reduce its leaves. Ficus virens have big leaves compared to other ficus species.

 

[amcoffeegirl]

Do you think this is the right time for ficus defoliation ? I have a ficus virens that I want to defoliate to reduce its leaves. Ficus virens have big leaves compared to other ficus species.

In Texas you could probably get away with it.
Leave the growing tips on.

 

[Starfox]

I was hoping to head off a debate about the "value" of this experiment by reminding folks of that their is value even from small comparisons like this, especially when genetic variations are minimized (cuttings from the same parent).

As I have tried to understand horticultural science as it applies to bonsai, I personally have struggled with the contradiction of: more foliage means more growth, increased ramification makes more foliage (leaves), and the admonition not to use techniques to increase ramification (pruning/defoliating/pinching) while the building the trunk.

Well it is what it is, I will take a bunch more cuttings today and then hopefully add them in Spring.
It'd be good if I had more ficus sp. to try as well but I don't.

I think much of the time when people talk of defoliation it is seen as setting the tree back, slowing it down and taking energy away from the roots. This is true of deciduous trees, I mean would anyone defoliate an elm 3 times a growing season?
Ficus on the other hand you can get away with it but it may turn out that over a period of years it is detrimental to the trees health, I'll try and find out one way or another.
I wouldn't recommend trying it on anything but ficus.

Interesting experiment.

When defoliating I would also cut the growing tips- but perhaps that is a different experiment.

That would probably be useful too but yeah, maybe for another time.
Who knows if I get a bunch more cuttings than I planned I can try that too.

The problem with drawing conclusions from a sample size this small (and you can't really go any smaller than 2) is, you might be getting a result for the wrong reason. The tree that you defoliate might grow a bigger trunk, for instance, but it might not be because of the defoliation - it might be that something you haven't accounted for is negatively impacting the other specimen. Then you go and apply what you think you've learned to your trees and you could actually be setting them back. If you add another variable like trimming shoots because of thrips, you further complicate things. I'd recommend using an insecticide rather than cutting.

I agree, it was a spurr of the moment thing yesterday and only had a couple of cuttings at hand but like I said I will address that and add a bunch more to the sample. As for the thrips most of the useful pesticides here are either banned or I need to do a course to be able to buy them, it's far easier to just pluck the affected leaves but if I can get my hands on a good preventative then I may as well give it a go.

Anyway, I defoliate my 2 willow leafs when I put them outside for the summer, because the old leaves have gotten ratty and removing them allows me to see the structure and make adjustments, wire, etc. There is always a strong surge of growth after the defoliation, but I don't know if it's stronger than what I would get if I left the leaves on.

Good luck with the project. Let us know what happens!

Same here, that is at least the reasons I have been doing it and I couldn't say either if the growth rate is more or less but if it creates more foliage then possibly more growth? But does it set the tree back at the same time to make it negligible?
I will post whatever results I get so I guess we will see.

 

[Mellow Mullet]

Do you think this is the right time for ficus defoliation ? I have a ficus virens that I want to defoliate to reduce its leaves. Ficus virens have big leaves compared to other ficus species.

I am not familiar with that variety of ficus, but you should have plenty of time for it to regrow in Texas. I would also only cut the leaves at the petiole and leave any latent buds intact. From what I have observed with the three varieties that I have is that some you can get away with taking it all on some varieties, some not. Ficus neriflora or whatever they are calling it nowadays you can cut anything you want and it will throw out new growth every where. Benjamina, cutting the leaves and latent buds off may cause it to die. Don't know about tiger bark, just started working with those.

Here is what I did to mine:
http://www.heartofdixiebonsai.com/c...cus-benjamina-defoliation-and-wire?Itemid=101

 

[MrBeto]

I am not familiar with that variety of ficus, but you should have plenty of time for it to regrow in Texas. I would also only cut the leaves at the petiole and leave any latent buds intact. From what I have observed with the three varieties that I have is that some you can get away with taking it all on some varieties, some not. Ficus neriflora or whatever they are calling it nowadays you can cut anything you want and it will throw out new growth every where. Benjamina, cutting the leaves and latent buds off may cause it to die. Don't know about tiger bark, just started working with those.

Here is what I did to mine:
http://www.heartofdixiebonsai.com/c...cus-benjamina-defoliation-and-wire?Itemid=101

Very nice work and interesting article ! I repotted and cut some big circular roots on this ficus a little more than a month. I’m not sure if is still a little early, or let it recover from the shock.

 

[Mellow Mullet]

Very nice work and interesting article ! I repotted and cut some big circular roots on this ficus a little more than a month. I’m not sure if is still a little early, or let it recover from the shock.

Again, familiar with this type of ficus some I am hesitant to say "go for it", but I have cut back/ heavy pruned and repotted all at the same time and had no I'll effects on the ficus that I have. They are very resilient plants.

 

[SuperMarioZZZ]

Did it yesterday.

 

[markyscott]

Very nice work and interesting article ! I repotted and cut some big circular roots on this ficus a little more than a month. I’m not sure if is still a little early, or let it recover from the shock.

Beto. Don’t defoliate tree in development. Leaves get little because tree gets weak. You don’t want a weak tree if it’s in development. Little leaves are for show. Big leaves mean strong tree - good for development. Thin leaves and/or cut them in 1/2, but don’t completely defoliate your tree. Save that for when you’re ready to show.

There are zero reasons to remove all the leaves on a bonsai in development.

S

 

[Starfox]

Do you happen to have links to things that people have written

This post has a lot of good info on the subject, would be nice if he cited the sources but I guess they can be dug up.

https://adamaskwhy.com/2016/10/26/i-use-some-fancy-words-to-justify-my-defoliation-habit-go-figure/

When defoliating I would also cut the growing tips- but perhaps that is a different experiment.

The above post addresses that issue, basically defoliate and leave the terminal bud alone for extended growth and thickness or defoliate and cut the terminal bud for shorter internodes and ramification.
Because, auxins.

From Adam....
It works; here’s how: By not pruning the terminal bud, it keeps the auxin intact, pushing length, I am not touching the roots, so the supply of cytokinin is stable, which keeps the ratio to auxin in an ideal stasis and encourages cell division and, therefore, girth. The damage (pruning) releases ethylene gas, which, with the presence of auxin, suppresses side growth. The lack of gibberellins (which are in the leaves, now defoliated) keeps the internodes shorter. Ethylene decreases gibberellins too.
I learned the technique from Jim Smith, and it’s been confirmed by generations of tree farmers trying to get taller, thicker trees as fast as they can.

 

[markyscott]

This post has a lot of good info on the subject, would be nice if he cited the sources but I guess they can be dug up.

https://adamaskwhy.com/2016/10/26/i-use-some-fancy-words-to-justify-my-defoliation-habit-go-figure/



The above post addresses that issue, basically defoliate and leave the terminal bud alone for extended growth and thickness or defoliate and cut the terminal bud for shorter internodes and ramification.
Because, auxins.

From Adam....
It works; here’s how: By not pruning the terminal bud, it keeps the auxin intact, pushing length, I am not touching the roots, so the supply of cytokinin is stable, which keeps the ratio to auxin in an ideal stasis and encourages cell division and, therefore, girth. The damage (pruning) releases ethylene gas, which, with the presence of auxin, suppresses side growth. The lack of gibberellins (which are in the leaves, now defoliated) keeps the internodes shorter. Ethylene decreases gibberellins too.
I learned the technique from Jim Smith, and it’s been confirmed by generations of tree farmers trying to get taller, thicker trees as fast as they can.

Read his article. Here are my thoughts:

1. I agree with his point that defoliation creates small internodes and little leaves. That’s how a weakened tree responds.
2. I disagree that removing a trees food source encourages the tree to grow thicker more quickly. What happens is that you’ll get more root growth for a time until auxin is restored (it essentially forces the tree into a spring reset), but the top growth essentially stops
3. I agree that removing the terminal bud will force the tree to push buds further back on the branch, but that has nothing to do with defoliation. If you remove the terminal bud even without defoliation this will happen. If you let the tree grow without pruning the growing tip this will happen also.

So why do it? There is no reason to weaken a tree in development in order to get little leaves. That’s what we do when we get a tree ready to show. If you want your tree to backbud, allow the branch to extend and get strong. You’ll get backbudding all along the branch. Then cut back to new growing shoot - that’s a huge drop in auxin and will encourage further backbudding far along the branch. If you defoliate and just pinch off the growing tip you’ll get a burst of growth out at the end - not where you want it. Trees in development that have been repeatedly defoliated all look the same - long straight branches with no branching close to the trunk and a burst of foliage out at the tips.

Scott

 

[Anthony]

If you increase Health and ramification to the genetic
limit, with as much sunlight as the tree can handle
The leaves come in smaller and branchlets are finer.

Defoliation is used only for tidying the work
Good Day
Anthony

* However, that does not always mean more dense

An example of Lush/Health --------- smaller leaves, full sun and ore branchlets.