Defoliation 101

[markyscott]

Laurus noblis I have one and have always wondered. I have cut old leaves in half which didn’t seem to do much. Maybe a timing thing?

Sorry ABC. I’ve never grown a Bay Laurel. I’ll ask around , but can’t give you advice on that one.

S

 

[Adair M]

I was actually thinking of Ume when I posed the situation, but it translates to multiple scenarios as you suggest. Another example of basics being applied being applied in a specific sense rather than just as an overall approach. Thanks for contributing the great posts above.

Ume have an entirely different protocol.

they’re different because of the blossoms. You have to keep a leaf if you want it to bloom. If you dont

Hi CC. Thanks for taking the time to post your pictures. Sorry to ask because of the technical problems you’re having, but can you point out which picture demonstrates that lateral buds are activated by defoliation alone without shoot pruning? It’s not clear (at least to me).

My experience is like this.
View attachment 304617

These extending shoots were defoliated and wired out, leaving a couple of leaves around the terminal buds. I did not shoot prune it as I wanted it to extend and thicken. The shoot originally ended about the same place the wire does. As you can see, no lateral buds were activated as a result of the defoliation. The shoot just continued to throw growth from the terminal bud.

S

That has been my experience, too.

I recently re-read one of the threads on “the hedging method”. And it appears that Walter gets backbudding (and ramification) because hedging is much like “shoot pruning”, as it cuts back the new growth, but keeps the interior leaves. So it “weakens the strong and strengthens the weak”, so to speak.

 

[River's Edge]

Ume have an entirely different protocol.

How does this comment fit Adair? Not sure what you are thinking or why you believe Ume cannot be part of a defoliation discussion.

 

[markyscott]

Yeah sorry these pics blow. I'll go get some better shots and try to update a proper post.

So in the large trident defoliated...
Over on the left you can sorta see a low shoot with leaves on the end. Blurred and tiny I know....sry. So that was defoliated but the tip growth was left uncut and it did regrow the new leaves without much new extension. The regrown leaves on the shoot is shown here. So it does seem to reflush even without cutting the tips too.

View attachment 304638

But for sure on a crepe myrtle I've never seen any latent growth/ramification from leaf removal. Only cut points. That's the first pic of the triple. Pretty much exactly what you referred to.

I'll look to see about what tropical pics I can drum up. I know with most ficus when leaving the growing tip while defoliating you will definitely get deeper budding. But this may be more of tropicals strictly reacting to the renewed sunlight on the interior and not any genetic reasons.

Just a couple of sketches to illustrate what I find difficult to understand about your picture. Here’s what I expect to see. Starting with a normal spring shoot:


It extends. At regular intervals it sets a node. At each node there is a dormant lateral bud waiting to be activated and a pair of opposite leaves. The leaves are connected to the shoot by a stem called a petiole. When we defoliate we cut through the petiole, leaving part of the stem connected to the shoot in order to not damage the dormant lateral bud at the base of the stem. If we shoot prune too, we cut off the terminal bud at the end of the shoot. When we’re done, it looks like this:


This is important. There are no leaves attached to the main stem. Where we’ve removed leaves there are cut petioles that remain. At the base of each petiole, there is a dormant bud that we’ve, hopefully, activated by pruning the shoot. After a few weeks, it looks like this:








New shoots extend from each of the dormant buds. There are still no leaves attached to the main stem. Instead, the shoot has thrown new shoots and the leaves are attached to them. In your picture:








I see an extended shoot. There are leaves attached and there are dormant buds at the base of each petiole. There are no secondary shoots that have extended from the main shoot. It looks all the world like the fist sketch above - a spring shoot that has not been pruned or defoliated. I take you at your word that you’ve defoliated it, but how it regenerated new leaves on the main shoot without activating any of the dormant buds and where the cut petioles went is a riddle, wrapped in a mystery, inside an enigma, but perhaps there is a key.

 

[Adair M]

How does this comment fit Adair? Not sure what you are thinking or why you believe Ume cannot be part of a defoliation discussion.

Sorry. I suppose you can defoliate Ume. I don’t. Well, I do remove the first two or three leaves on each twig after the new growth had extended. I guess that’s a “partial defoliation”. Then, I cut back the new growth about half. In mid May.

The purpose for this protocol is to have flowers AND ramification. Ume flowers on current year’s growth, and the flower buds are at the base of the leaves. No leaf, no flower bud. The reason I removed the first couple leaves is where those leaves were will produce a vegetative bud. That is, they can still produce a new shoot next year. Sometimes, a bud that produced a flower will not send out new growth. By removing the leaf, no flower, but it will send out new growth next year. That’s how ramification can be built. And you’ll still get flowers where the leaves were. After the flowers bloom, cut back to the vegetative buds.

I have heard of people defoliating Ume, but I don’t.

 

[ABCarve]

My experience with broadleaf evergreens is pretty much restricted to oaks, olives and tropicals. Was there one in particular you were interested in? If it’s not one of those, I can try and find out.

- Scott

How about Natal plum?

 

[one_bonsai]

Does Bjorn's video apply to Tridents?

 

[River's Edge]

Sorry. I suppose you can defoliate Ume.

I have heard of people defoliating Ume, but I don’t.

I was aware of that traditional basic protocol for Ume! Often there are specific reasons for considering aspects of different protocols. Bjorn does a good job of exploring some of those ideas in his video on defoliation and Japanese Apricot.

 

[markyscott]

Sorry - having connection problems. I’ll try again.

Yeah sorry these pics blow. I'll go get some better shots and try to update a proper post.

So in the large trident defoliated...
Over on the left you can sorta see a low shoot with leaves on the end. Blurred and tiny I know....sry. So that was defoliated but the tip growth was left uncut and it did regrow the new leaves without much new extension. The regrown leaves on the shoot is shown here. So it does seem to reflush even without cutting the tips too.

View attachment 304638

But for sure on a crepe myrtle I've never seen any latent growth/ramification from leaf removal. Only cut points. That's the first pic of the triple. Pretty much exactly what you referred to.

I'll look to see about what tropical pics I can drum up. I know with most ficus when leaving the growing tip while defoliating you will definitely get deeper budding. But this may be more of tropicals strictly reacting to the renewed sunlight on the interior and not any genetic reasons.

Sorry CC - All of a sudden, I can’t post any images either. If something fixes itself, I’ll complete the post I started up above. Very frustrating.

- Scott

 

[markyscott]

Does Bjorn's video apply to Tridents?

yes - if your goal is building basic branch structure, I do the same with Tridents as what he describes with Ume. One big difference is that early on you are wanting your shoots to extend strongly to build caliper. For that purpose I just defoliate the older leaves and leave those around the growing tip. That encourages the shoolt to extend rather than throw side shoots. I do the same with most broadleaf hardwoods, in fact. One difference between what Bjorn does and what I’ve been taught is to just defoliate the interior nodes. That will encourage vegetative buds there and will keep the flowers out near the ends of the shoot. That way when you cut back to vegetative shoots, you’re also compacting the tree. But there are different techniques for different purposes. Bjorn describes that in the post. That’s why Ive tried to organize this discussion around objectives. What are you trying to accomplish with your trident?

- S

 

[choppychoppy]

I

Sorry - having connection problems. I’ll try again.



Sorry CC - All of a sudden, I can’t post any images either. If something fixes itself, I’ll complete the post I started up above. Very frustrating.

- Scott

I did a complete defoliation today so ill try to get up a full progression of the whole year on this thing. I've got pretty complete shots since I'm using it for intensives. Then we can compare notes.

 

[markyscott]

I

I did a complete defoliation today so ill try to get up a full progression of the whole year on this thing. I've got pretty complete shots since I'm using it for intensives. Then we can compare notes.

Cool. Maybe we’ll be able to post pictures by then.

s

 

[Maveri9720]

Hey Scott. First off, thank you so very much for posting this invaluable information, as I'm still new and trying to learn as much as I can and having all of these different situations and different techniques all provided in one easy to read thread with pictures is a perfect reference for me. I do have a very basic and easy question for you that I would like to know and I'm sure would benefit others as well: When letting young and thin branches grow out to thicken up, do you let them grow completely untouched until you reach the desired branch thickness and then cut back or are there steps/techniques that can be taken along the way to help this process?

Personally, I have a couple of trees that have thick trunks, that I've cut back pretty hard due to poor branch placement or they don't fit the intended design and now I have young, thin branches in the correct positions and need them to thicken up to balance against the thicker trunks. Some of these branches are the first lower branches, so those are a very high priority to thicken up quickly (Water Jasmine, Bougainvillea, Buttonwood, Brazilian Rain Tree). I would very much appreciate your input and advice, as well as others. Thank you in advance!

 

[markyscott]

Hey Scott. First off, thank you so very much for posting this invaluable information, as I'm still new and trying to learn as much as I can and having all of these different situations and different techniques all provided in one easy to read thread with pictures is a perfect reference for me. I do have a very basic and easy question for you that I would like to know and I'm sure would benefit others as well: When letting young and thin branches grow out to thicken up, do you let them grow completely untouched until you reach the desired branch thickness and then cut back or are there steps/techniques that can be taken along the way to help this process?

Personally, I have a couple of trees that have thick trunks, that I've cut back pretty hard due to poor branch placement or they don't fit the intended design and now I have young, thin branches in the correct positions and need them to thicken up to balance against the thicker trunks. Some of these branches are the first lower branches, so those are a very high priority to thicken up quickly (Water Jasmine, Bougainvillea, Buttonwood, Brazilian Rain Tree). I would very much appreciate your input and advice, as well as others. Thank you in advance!

Let the new branches grow. They don’t have to get all the way to the desired thickness, but 2/3 or so would be good. And remember. you’ll cut most of that off. Watch for new shoots to emerge on the top of the branch and use them to create your new leader. Wire it down and let it continue to extend. Rinse, repeat and after a few seasons you’ll have a good primary branch with movement and taper - maybe a few secondaries too. Then you can start on the next stage.

- Scott

 

[Maveri9720]

Much appreciated. Thank you again for your time and knowledge!

 

[River's Edge]

yes - if your goal is building basic branch structure, I do the same with Tridents as what he describes with Ume. One big difference is that early on you are wanting your shoots to extend strongly to build caliper. For that purpose I just defoliate the older leaves and leave those around the growing tip. That encourages the shoolt to extend rather than throw side shoots. I do the same with most broadleaf hardwoods, in fact. One difference between what Bjorn does and what I’ve been taught is to just defoliate the interior nodes. That will encourage vegetative buds there and will keep the flowers out near the ends of the shoot. That way when you cut back to vegetative shoots, you’re also compacting the tree. But there are different techniques for different purposes. Bjorn describes that in the post. That’s why Ive tried to organize this discussion around objectives. What are you trying to accomplish with your trident?

- S

Just to clarify my comments about Ume! Here is a couple of snapshots with different objectives! laterals are defoliated and cut back. Apical on one Ume is left alone but the laterals are defoliated and apical tips on the laterals were cut back. Other two pictures show the second set of leaves beginning with remaining petiole stub still in place. These were done about three weeks ago! Double aluminum wire for safer bending to create some movement. Major growth will be the focus after some branch structure is established! Note: these are " Kobai " and they are vigorous, they pushed over four feet of extension last year! Will be interesting to see the overall results this year.

 

[markyscott]

With the my connection problems solved for now, I’ll get back to it. I thought some examples might be good. Here’s a tree - a Shohin willow leaf ficus. This tree is in refinement and I’m preparing for the National Show in September. So the objectives here are to control growth, increase the density of twiggy shoots, keep interior shoots alive and balance energy. Note I’m not worried about small leaves now. I’ll completely defoliate either A) a few weeks before the show to show it with a fresh flush of young leaves or B) immediately before the show and show it without leaves. I haven’t decided yet.



The tree has gotten quite dense and the interior is getting shaded out. Left alone, it could easily lose interior shoots. I’ll need to cut back, thin and remove foliage Masson the outer canopy.

S

 

[markyscott]

Here are photos taken after the work is done.

 

[markyscott]

I shoot pruned back to two leaves and defoliated the outer canopy. I left two leaves on the interior shoots. Then I leaf cut. I tried to leave less foliage on strong branches and on apical growth and more on weak branches and basal growth.

There is an important caution when doing this work. Leaves on interior shoots have developed in the shade. Exposing them like this can cause leaf scorch. So introduce the tree back into the sun carefully

 

[sorce]

pictures

I'd love to edit them into the post of you'd like.

Please PM me.

That was like Japanese porn.

Sorce