Sacrificial Limbs

[Attmos]

Best time of year to make the sacrifice..? lol Simple question.
I'm guessing it would be the dormant months.
It's a cottonwood, my first attempt.

 

[River's Edge]

Best time of year to make the sacrifice..? lol Simple question.
I'm guessing it would be the dormant months.
It's a cottonwood, my first attempt.

Major pruning is best carried out just prior to the growing season. That way the plant can begin healing. If your intention is to leave a large stub and finish the cut at a later time then go for it. If your hope is for new shoots in the vicinity of the cut than wait till spring.

 

[Attmos]

Major pruning is best carried out just prior to the growing season. That way the plant can begin healing. If your intention is to leave a large stub and finish the cut at a later time then go for it. If your hope is for new shoots in the vicinity of the cut than wait till spring.

Thank you.

 

[Attmos]

Major pruning is best carried out just prior to the growing season. That way the plant can begin healing. If your intention is to leave a large stub and finish the cut at a later time then go for it. If your hope is for new shoots in the vicinity of the cut than wait till spring.

Does that apply to root pruning as well?

 

[badatusernames]

Major pruning is best carried out just prior to the growing season. That way the plant can begin healing. If your intention is to leave a large stub and finish the cut at a later time then go for it. If your hope is for new shoots in the vicinity of the cut than wait till spring.

I somehow became convinced that late spring was good because the tree has built up energy by then and may produce more buds, do you have any options on that?

The healing aspect seems obvious, but I’m wondering about trying to grow more branches naturally vs grafting

 

[pandacular]

My teacher will often “saw cuts means summer”.

Also, the only person I know working on cottonwood is @MaciekA

 

[Shibui]

Maybe not quite as simple as it first appears.
Definitely depends on species.
May depend on local climate.
May also depend on what associated outcomes are expected.

Down here I start hard pruning some deciduous after leaf drop. They probably don't heal much through winter but there's little risk of infection and they will begin healing as soon as they can in Spring. Also hard prune through summer.
Can also prune conifers all year round so I remove sacrifice branches whenever I see the need and have the time.
Need for new buds is an interesting one. I have not taken enough notice to make a call on that.

Root pruning definitely depends on species. I root prune trident maples from mid winter through to leaf out. Some others have not liked early root pruning so better left until closer to buds opening. Don't have any experience with cottonwood to be able to give an informed opinion. The few weeks before buds opening seems to be generally good for most deciduous.

 

[River's Edge]

Does that apply to root pruning as well?

Depends on the species and your climate. Some root pruning can be very effective with conifers late august/early fall when a second growth pattern occurs for root development. This is often used to complete repotting that was begun with a 1/2 HBR in the spring.
Generally not the best time for most species.

 

[River's Edge]

I somehow became convinced that late spring was good because the tree has built up energy by then and may produce more buds, do you have any options on that?

One should ask oneself if the buds form as a result of the timing of cut back, will the buds have sufficient time to become strong shoots prior to dormancy if the species and climate requires that consideration. General questions that lack a species and climate reference can be very misleading. In some cases the timing simply means a delayed response, in others it means lack of success.

 

[Attmos]

Also, the only person I know working on cottonwood is @MaciekA

Yeah, lol, I've been told by several people that cottonwood doesn't make the best bonsai... or even a good one really.
It was just one that sprouted randomly in a pot full of dirt outside and I said, "What the hell".

Four years into this tree's growth has really shown me why people dislike them, and that doesn't even count the fact that the leaves won't reduce in size.

But I think it's been a good learning experience. Next spring I plan to get more trees.

 

[Attmos]

My teacher will often “saw cuts means summer”.

Is there a typo in this because I'm not exactly sure what it means...

 

[Attmos]

Maybe not quite as simple as it first appears.
Definitely depends on species.
May depend on local climate.
May also depend on what associated outcomes are expected.

Down here I start hard pruning some deciduous after leaf drop. They probably don't heal much through winter but there's little risk of infection and they will begin healing as soon as they can in Spring. Also hard prune through summer.
Can also prune conifers all year round so I remove sacrifice branches whenever I see the need and have the time.
Need for new buds is an interesting one. I have not taken enough notice to make a call on that.

Root pruning definitely depends on species. I root prune trident maples from mid winter through to leaf out. Some others have not liked early root pruning so better left until closer to buds opening. Don't have any experience with cottonwood to be able to give an informed opinion. The few weeks before buds opening seems to be generally good for most deciduous.

Thank you. I know it it's easy to talk about cottonwood because no one uses them, so I appreciate the approximation.

 

[pandacular]

Is there a typo in this because I'm not exactly sure what it means...

He means that if you're making a cut large enough to require a saw, it's best done in early summer/late fall--after the first flush of growth hardens off. Another great time to make big cuts, as Frank and Shibui mention is just after leaf drop. This is especially true on species that are prone to bleeding, like maples. I don't know about cottonwood specifically, but I imagine you'll need to be pruning them many times a year (probably 3+).

As always, there is a lot of nuance, but "saw cuts in summer" is a useful memory tool to me.

edit: and yes i think there was a typo...should read "saw cuts mean summer", maybe that's clearer.

 

[Attmos]

He means that if you're making a cut large enough to require a saw, it's best done in early summer/late fall--after the first flush of growth hardens off. Another great time to make big cuts, as Frank and Shibui mention is just after leaf drop. This is especially true on species that are prone to bleeding, like maples. I don't know about cottonwood specifically, but I imagine you'll need to be pruning them many times a year (probably 3+).

As always, there is a lot of nuance, but "saw cuts in summer" is a useful memory tool to me.

edit: and yes i think there was a typo...should read "saw cuts mean summer", maybe that's clearer.

Thanks for making it clear.

 

[Attmos]

He means that if you're making a cut large enough to require a saw, it's best done in early summer/late fall--after the first flush of growth hardens off. Another great time to make big cuts, as Frank and Shibui mention is just after leaf drop. This is especially true on species that are prone to bleeding, like maples. I don't know about cottonwood specifically, but I imagine you'll need to be pruning them many times a year (probably 3+).

As always, there is a lot of nuance, but "saw cuts in summer" is a useful memory tool to me.

edit: and yes i think there was a typo...should read "saw cuts mean summer", maybe that's clearer.

If that's true, maybe I should make the cut now. It's dropped all of its leaves...

 

[Attmos]

Maybe not quite as simple as it first appears.
Definitely depends on species.
May depend on local climate.
May also depend on what associated outcomes are expected.

Down here I start hard pruning some deciduous after leaf drop. They probably don't heal much through winter but there's little risk of infection and they will begin healing as soon as they can in Spring. Also hard prune through summer.
Can also prune conifers all year round so I remove sacrifice branches whenever I see the need and have the time.
Need for new buds is an interesting one. I have not taken enough notice to make a call on that.

Root pruning definitely depends on species. I root prune trident maples from mid winter through to leaf out. Some others have not liked early root pruning so better left until closer to buds opening. Don't have any experience with cottonwood to be able to give an informed opinion. The few weeks before buds opening seems to be generally good for most deciduous.

Thank you. I apologize for not responding sooner.

Leaves just dropped and it's getting colder. This cut I'm making is really a trunk cut, but the trunk is only about 3/4 of an inch in diameter. The branch below the cut will become its new leading shoot.

So, about now is actually a good time of year you think?

 

[Mike Westervelt]

No not a good time now, species that are inclined to lose branches and twigs randomly like alder, cottonwood, birch, aspen should only be hard pruned while actively growing
so they can compartmentalize the wound and heal in a timely manner.

 

[pandacular]

No not a good time now, species that are inclined to lose branches and twigs randomly like alder, cottonwood, birch, aspen should only be hard pruned while actively growing
so they can compartmentalize the wound and heal in a timely manner.

Another piece of (unsolicited!) advice*: species/genus specific advice generally trumps all--especially when it's local as well.

*to the OP, not to you Mike!

 

[Shibui]

No not a good time now, species that are inclined to lose branches and twigs randomly like alder, cottonwood, birch, aspen should only be hard pruned while actively growing
so they can compartmentalize the wound and heal in a timely manner.

This is good species specific advice. Birch was on my mind when I wrote " depends on species" as I have experienced die back after pruning those in winter.
I'd go with @Mike Westervelt advice here.

 

[MaciekA]

@River's Edge and @Mike Westervelt have answered the direct questions well so I will add a note on specifically learning cottonwood and deciduous techniques for the first time simultaneously, just in case you find yourself muttering "cottonwood doesn't work for bonsai" a couple years from now. Brace yourself for a steeper learning curve especially as you begin to develop branches or experiment with defoliation etc. Cottonwood is not Japanese Maple or Hornbeam, vigor is easy, control is more challenging.

Cottonwoods, poplars, aspens and willows (i.e. salicaceae) are more firmly in the "you need to know, not guess" department and this is not immediately obvious when you start growing them right up until you lose your first really big section of growth. So, if you can, I wholeheartedly suggest finding someone who grows a species in this family to study with / talk to on a season-by-season basis so you can pick up the ins and outs of willow-family species in addition to learning all the deciduous basics first. I want to be as respectful as possible in saying this, but the original question and followup questions of this thread are day 1 deciduous 101 questions whereas cottonwoods/willows are decidous 301 with a prerequisite of 101 and 201. For cottonwoods, IMO it is not sufficient to merely say "cut at the safe times, which are <such and such>". You can lose anything from a whole branch to the entire upper half of a tree by ignoring sucker growth, for example. Disjoint tips & tricks and google searches and random questions on forums aren't a great way to navigate all the way through from 101 to 301, if you catch my drift.

Another wise bnutter (I forget who, if you are out there please ID yourself) eloquently said something about willows akin to "you need to decide for the willow or it will decide for you" and this is even more aggressively true for cottonwood. After messing around with other populus (eg: p. nigra) and then also various salix species, I believe this applies to all of salicaceae. If you find yourself frustrated with the species later on, dwell on that bnutter's statement.

@pandacular there are also some larger-sized black cottonwoods at Rakyuo bonsai now (perhaps you spotted these when you were there recently). These will hopefully help answer some questions about branching stability / ramification faster than what I'm doing.