Can you bend think trunks?

I’m trying to find an old Colorado Spruce. Their trunks are nice and fat, and tall! For example, there’s the one below I have my eyes on. Would I be able to bend the trunk though? What gauge wire would I need? I’m guessing it would take a few years of slowly twisting?

no bending possible. Way to go is wedge cut and rebar imo.

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I’m also very much a bonsai beginner so take this with a grain of salt but I don’t think it’s necessarily impossible, just very very hard.

I recently did some bending of a noble fir which was maybe a little over half the diameter.

To do it you are going to need a way to apply a huge amount of force (without cutting into the trunk). A come along of any reasonable size with enough bracing and padding should do it. On the positive side you have a lot of length to work with to act as a lever arm. I also recommend the technique where you split the trunk along it’s length perpendicular to the direction of bending. In your case you will probably want multiple such splits each parallel to the others. I know this technique works with elongating species such as noble fir or spruce, it makes bending slightly easier (but have no illusions it’s still a bugger).

One challenge you might encounter is finding a trunk splitter large enough to do the job, mine just barely made it.

Wire is going to be almost useless in this case but I do recommend wrapping the bend site in rafia after you are done to make sure your splits are able to heal together properly.

To be honest though I wouldn’t try to bend that tree much at all, maybe a really delicate bend but personally I think that tree is best suited for formal upright or something similar. Not every bonsai needs to have hairpin bends to be interesting and attractive.

This is what originally inspired me towards the idea. I guess it’s just incredibly challenging?

When you say perpendicular cuts, do you mean wedge cuts like Ryan does in his bending video? Where he uses a steel bar.

Do you have any examples of what a final design might look like if I were to keep this upright? This tree is over two meters tall, and I’ve always thought of bonsai as much shorter.

FWIW Ryan says he only does wedge cuts on pines and has never tried it on an elongating species or deciduous. Theoretically it should work but it’s not something he’s recommended in the past.


I definitely understand wanting to do something similar but those trees are significantly smaller than the one you’re considering.

No what I did is different than wedge cutting, I think it was herons bonsai on youtube where I saw it first. you effectively split the trunk along the vertical.

I was under the impression that wedge cutting wouldn’t work on a elongating species like spruce but I really have no idea, if it does then that would definitely be the way to go. But it’s still really hard to do correctly (or so I’m led to believe).

as far as ways to shorten the tree (other than going for some extreme bending) I know of three options.

One is to choose one large branch which will become your new apex and cut the trunk above it. You then bend that branch upwards. I know it seems like it would look dumb but after enough time it will begin to look more natural. You see this kind of operation done a lot actually. It’s one way folks make trunk taper granted it works best with deciduous species.

The other option for shortening is to air layer the top of the tree thereby essentially discarding the lower portion (or perhaps making a second bonsai out of it). This might be what I would try in part because I’ve always wanted to try air layering. As I understand it elongating species will work reasonably well with air layering but are harder to do than deciduous.

A third option would be to jin the top and carve it down substantially to make it look as though the top died and then broke off. It would take work and time to get the proportions correct but that could make for a really nice tree eventually. And spruce actually lends itself to large jins really well since they commonly do that in nature.

or hey maybe you could do both, air layer the top then jin the new cut off apex of the lower section.

I’m sure there are other approaches to take here but that’s what I can think of.

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thank you for chiming in.

One is to choose one large branch which will become your new apex and cut the trunk above it.

Do you then bend that branch upwards?

air layer the top of the tree

I’ve heard and this and would like to try it at some point. Wouldn’t the trunk be thinner near the top and thus you’d lose out on the thickest part of the trunk?

jin the top and carve it down substantially

This is my favourite of all your suggestions! Although I have zero skill on how to do this, but I’m meeting a bonsai teacher this weekend I’ll try remember to ask him about this.

Thanks for sharing your ideas! The other thought I have is to look for a smaller spruce, practice these skills on something easier and cheaper and work my way up to this size.

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Yeah, I remember his comment on that. Is it because the spruce has a more fragile trunk and thus more likely to buckle under the stress? Pine’s are quite tough.

It has to do with how the tree moves resources. If the tree is vein specific (like junipers) a wedge cut could kill everything above and below the cut. Pines can bypass the wedge and move water around the cut.

Oh, I thought that distinction was between deciduous and coniferous. Thanks for clearing that up for me!

Yeah and some deciduous become vein specific too, so you can’t really say yes or no to all deciduous species with a broad stroke like that.