AusBonsai

So my little pride and joy just about died this week. Most leaves are a bit crispy.

I want to cut some roots and cut the trunk.

How high generally would you make the chop? Around the 20cm mark usually?? Not really sure. I don’t want it to be massive but it will obviously grow from there. Do you chop much lower for it to the grow?

If it were mine I would chop the trunk about 5 cm above the first branch and cut the first branch back to about 10 cm long. I wouldn't touch the roots now. If it is in a poor potting mix perhaps slip pot it into a better mix and in the process tease the existing roots out a little so they grow into the new mix faster. Then allow it to regain strength with regular application of liquid fertilizer such as Powerfeed or Charlie Carp until next spring.

This is a Euc I believe.
It has certainly dried out enough for the tree to with hold water from the leaves. That's a strategy for survival - ditch the leaves and keep the core alive and hope for water soon. After there is water it can grow new leaves.
One of the reasons for trees drying out is being root bound. Roots continue to grow and, in a pot, eventually there's no more room for water or air and the pot dries out quicker every day. I have noticed that spring is when I usually see the results of this as trees are using more water and days, increasingly warm and dry and root growth is rapidly filling any remaning space.
One way to overcome is to soak the pot regularly to really wet the root ball, some growers find sitting the pot in a tray of water works for a while.

Ultimately the tree needs to be repotted because the problem will only get worse. Late spring and summer is quite a good time to repot eucs - see Rory's recent post about repotting in hot weather - https://www.ausbonsai.com.au/forum/view ... 52#p285052
I would prefer to repot and root prune rather than slip pot which will do little to fix the underlying problem. Slip potting can sometimes introduce another unintended set of problems.
I have some self sown euc seedlings growing along the driveway here and I'm intending to dig those soon.

Trunk chop: Try to think in terms of final bonsai height rather than fixed cm. I think 1/3 estimated final height is a good spot to do the initial chop on trees that can bud from bare wood. Cutting above a branch does have added safety knowing there should be dormant buds on the branch or in the branch collar but I think the first branch on this one is too high relative to the trunk thickness.
Note that most Conifers and other trees that do not back bud well MUST be pruned to leave some active green shoots.
Eucs are very good at sprouting new shoots from epicormic buds and from the base. Most eucs can be cut anywhere with good results.

Yep it’s a river red gum.
I have had it in a bucket and had water in the bucket which it would just suck up very fast but this got left and also dried out and hence all the dead leaves.

I thought the same that the first branch is really too high for anything final. I don’t want a huge tree.

If 1/3 is a guide then maybe at about the 10-15cm height for the trunk chop might work?? Would that seem to be ok?

So can I trunk chop AND root prune at the same time?

I usually do both roots and trunk when I dig eucs. Most have survived but I do have occasional losses.
River red appears to be one of the easier species. Many years ago I was told they can have all the trunk removed and all roots removed and just replant the lignotuber and they will still grow. I don't usually go that far but they do manage to come through almost everything.
Now, while yours is recovering from the recent drought, would be an ideal time to do the work you need as it will be primed to resprout now.

10-15 cm trunk chop would seem OK for a 3 cm thick trunk.

Good luck

Forgot to add some photos of the eucs in our driveway I mentioned above.

2 trees dug.
One smaller: The other one is a little bigger but still only a couple of years old at most. I forgot to take photos of after potting

Hi Jessepap,
I have a young river gum that I recently repotted - cutting roots and branches hard. It was punch drunk for a week or so but it is loving life now. Cheers, Mark


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So prior to the last couple of posts I did a root prune and a trunk chop.

The roots were pretty bound and I took about 50% off before I got nervous and stopped. Probably could have taken more.

So I have about 5 little buds forming which is great.

A couple of them a very low close to the base of the trunk.

Do I just let these grow for now or is it best to pinch them off?
I doubt these would be long term branches I assume as they are likely too low to the base??
Cheers

Really low euc buds tend to grow really strong and fast. I have had some where the higher buds were slower and eventually died off leaving just the strong basal regrowth.
Any shoots are good after a severe chop like this. All leaves feed the new roots and the whole tree so it is usually advised to let everything grow for a while after trunk chop so the tree regains some strength.
So there's a dilemma. Do we leave them alone to help the tree recover or get rid of them to make sure the existing trunk continues to grow?
I would probably try a middle road. Leave them for a while to help recovery but remove them if/when they grow taller than any useful trunk buds.

I would love to see a wide scale test with Eucs and new shoots that are allowed to grow from the base or lignotuber, and whether this affects the main trunk or not.
From my experience with the Eucs I have grown, it does not affect or impact the main structure. Although there are about 700 species of Eucs, so its only from the ones I've trialed.
I am curious though, whether on the odd occasion that the main trunk or upper growth is perhaps not in the best of health or affected with the internal structure from foreign invaders or disease and such, thus allowing the lower shoots to grow healthy, while the upper structure lags. This may then imply to the grower that allowing the lower growth to flourish, has taken the vigor away from the top.

I have always allowed lower growth to develop and compliment Eucs, but a large scale test would be fascinating. I doubt there would be enough older material in Australia for Euc bonsai to test this sort of situation though.

Presumably when you look at Gums in nature, there are numerous situations where its clear the shoots from the base have developed strongly and grown with no adverse affect on the upper structure. But by that rationale, you haven't seen the ones that may have had their upper structure affected as its died off.

Fantastic. Thanks guys. It’s all really interesting.
Couple of pics for reference.

I also just noticed a very tiny bud right at the top where I cut the trunk. Pretty sure my eyes are not tricking me. This river red is such a strong and hardy tree. Unreal.

Also trunk chopped the sideroxylon

It’s put out 3 nice little shoots.

This had numerous tiny shoots from the very very base which I pinched off. Didn’t see much benefit to those.

My feeling is that you knock off all the low stuff as soon as you see growth higher up where you want it. Not before. Then in a week or three you come back and select the one or two shoots at each shoot point that you want to keep, and get rid of the million or so other randoms in the general area. If you want trunk thickening, only keep two or three shoots overall, and grow them very long without pinching. If you are refining, then the opposite. PICK GOOD ANGLES! Don't keep stuff that doesn't look good, or interesting. I'm talking in part about the shoots that loop out from the trunk, then continue on the same line as the original trunk - that will pretty much never look any good. I insist that my trees look a damn sight better than I do.

Gavin

GavinG wrote: ↑January 3rd, 2021, 1:43 pm Don't keep stuff that doesn't look good, or interesting. I'm talking in part about the shoots that loop out from the trunk, then continue on the same line as the original trunk - that will pretty much never look any good. I insist that my trees look a damn sight better than I do.

Gavin

Cheers. Do you mean say a shoot that just grows straight up to the sky the same way the original trunk does?