Questions about how to heavy prune different trees

[Oleg]

Hi all,
I was finding the thread about callousing in the tropicals forum very interesting in that I have had a few surprises in the way some of my pruning has calloused. I didn't want to hijack the intent of that forum so I started this one. Similar in approach though, which trees would you prune leaving a stub, flush cut, and when would you use a concave cut?
JWP
JBP
JRP
Mugo
San Jose Juniper
White Cedar
Ficus
Chinese Elm
JM
Cherry

 

[Wires_Guy_wires]

That's a trick question. Because it really depends on what kind of thing I want to end up with. It depends on the material and your goal. And the amount of time you want to spend on healing something.

I think conifers can handle stubs, but they seem to close their wounds relatively fast so concave could work as well. Flush cuts don't look good because they'll always end up looking man made. Except for when the branches are thin and a flush cut would look inconspicuous.
Non-conifers can handle stubs (but they need protection from rotting, unless that's your goal! Which is why this is a trick question..) and will usually roll over concave cuts. Depending on how they heal, I think flush cuts can work too. Branch thickness is as important as above.

You can make a graffiti drawing with a pen, but it's way harder to write a normal sized letter with a spray can. What if you have a spray can and you want to make a statue? You put the spray can down, go out and get some marble. I think it works the same way with pruning; you do what fits your goal. And in doubt, do nothing.

 

[Oleg]

Yes branch thickness is probably the issue, I am talking about larger branches. I flush cut a Cherry and the growth around it formed two obvious ridges around the wound creating a reverse taper. I did the same on a Chinese Elm a couple of years ago and it looks okay but there is still a slight ridge to each side of the cut so I thought I would try and grind the wound down a bit on a cut I made this year. I was wondering if leaving a stub, if it wouldn't shrink as it dried disrupting the sap flow less and reducing the size of the ridges, then cut the smaller dry stub in a year or so. I guess I was hoping for an approach that would lead to healing without a scar.

 

[Leo in N E Illinois]

It depends, is the only answer one can give to this question.

The current state of health of the actual tree in front of you will determine what you can do. All the species you listed can tolerate heavy pruning if done when the tree is in a state of good health and vigor and the pruning is done at the optimum point in the yearly growth cycle.

For each species there are differences in timing. For all the species listed, if in a state of good health, the trees will survive. If the trees are in poor health, or the pruning comes at a bad time of year, decline or death will be the result.

Seriously - the health of the actual tree in front of you plus correct timing for your individual climate, totals to 100% the determining factor for success. Nobody on the internet can tell you "theoretical" advice that will mean anything.

That said - Ficus, and Chinese elm will be the two that are most forgiving of mistakes or excess exuberance in pruning.

 

[Leo in N E Illinois]

For each species, you need to learn what good vigorous growth looks like. This is not a trivial task. For two decades I had trouble with JBP failing on me. I visited a bonsai friend and for the first time saw live in person what a vigorous healthy JBP looks like. Turns out I had been mistaking weak growth as a sign of vigorous growth. I was constantly working on trees that needed to recover vigor. Now that I learned what a vigorous JBP looks like, I stopped loosing them. I have some now that are over a decade old.

So, for each species, growth them out and learn what a healthy tree looks like. Get them healthy and vigorous. Then you will be able to get away with drastic pruning. Until then - go slow.

 

[Oleg]

The Ficus and Chinese Elm have shown the best results, I have been seeing reverse taper on others as a result of work I have done, today I saw some failed grafts in a thread which resulted in a bulge. I should probably make a post on all large cuts to make sure timing etc. is right.
Thanks for your time and info.