Liquidambar with many competing leaders and possible rot in crotches

[alg]

We have a large, established liquidambar tree with many competing leaders (the trunk is ~1m (3') diameter but 2 m (6') from the ground it divides into 10 or so ~300 mm (12") diameter branches). I've attached some photos.

 

It dropped a large branch about 1 year ago, exposing some obvious rot in the branch crotch.  We are worried because many of the remaining crotches collect a lot of leaves and debris--several containing damp soil when you dig down into it, and with saplings of some other species growing in the soil in the crotch. A few of these remaining branches would land on the house if they fell.

 

Other than this, the tree seems really healthy.

 

We would really like to keep the tree--it gives great seasonal shade and really sets the vibe of the whole property--but we also worry every time there's a strong wind.

 

Any advice on how best to manage the tree would be really appreciated.  We've struggled to get a local arborists to assess the tree (the one who comes recommended isn't taking new work, and others seem to only quote for removal).  For example:
- Should we be removing whatever soil, etc. we can from the crotches?
- Is there a way we can assess the extent of rot and risk?
- Is heavy pruning an option (one arborist told us removing the top of all leaders would stress the tree too much)?
- Is cabling, or some other reinforcement, an option?

 

Thanks very much in advance!

 

[Mick Dempsey]

Looks to me as if it’s already been heavily pruned a good few years back at about where I’ve drawn the line.

Some included bark in the crotches.

I would suggest a reduction to the previous points, liquidambers respond readily to pruning so should be ok.

 

Many people won’t agree with this course of action though, just my opinion.

[Dan Maynard]

1 hour ago, Mick Dempsey said:

Many people won’t agree with this course of action though, just my opinion.

Seems like the only other practical option is remove the whole tree though.

 

Then repollard every 3-5 years to stop it getting so big again.

[Mark Bolam]

5 hours ago, Mick Dempsey said:

Looks to me as if it’s already been heavily pruned a good few years back at about where I’ve drawn the line.

Some included bark in the crotches.

I would suggest a reduction to the previous points, liquidambers respond readily to pruning so should be ok.

 

Many people won’t agree with this course of action though, just my opinion.

 

I’d go with that Mick, but wait until late autumn.

[Rich Rule]

Where is the tree?  Ie where do you live?

 

I have never really heard anyone in the Uk say they like a tree because it provides shade.

 

Therefore, if you live in a hotter climate then the advice given by UK arborists may not be that suitable.

[Mick Dempsey]

I assumed it was in the US, judging by the house and what the other tree blokes said.

[alg]

Thanks, that's really helpful.

 

We're in Australia, close to Sydney.  So it's a pretty temperate climate - the summer shade and winter sun we get through this tree both improve conditions in the house a lot.

 

The approach Mick suggested sounds good to me.

 

The other advice we've received was to cut the branches with potential rot back to the trunk, and that 'topping' the tree would make things worse (I guess by encouraging more growth down low?).  I realise there's probably more than one way to skin the cat, but what would your thoughts be on that approach?  I might try to dig out all soil and debris I can from the crotches today to see if I can find any actual rot - I guess the best approach might depend on that?  Although I suspect it will be difficult to tell how much damage there is.

 

I found a few blurry phone photos of the branch that came down about a year ago (attached below).  It looked like soil and water (and roots from a sapling) had worked their way about 500 mm down into the crotch, splitting it from the trunk.  It came down under its own weight (i.e. without wind).

 

Thanks again!

 

Edited June 18, 2023 by alg

[Mick Dempsey]

The tree has poor form, meaning the way it has grown lends itself to that kind of failure.

 

All you can do is re-top/pollard it, get someone who knows what they’re doing so the make a nice shape and with a bit of luck it’ll come back well (it’s already been done once and survived) repeat the process every 5/10 years and you’ll have shade and the house will be safer. Short to medium term that’s your best solution.

[alg]

No worries - thanks again for your advice!