Thoughts on this Ginko?

[Thesnarlingbadger]

Hi all,

 

 I’ve posted this in fungi pics because I couldn’t find a better topic under tree health care.

 

 I have been asked my thoughts on a customers ginkgo tree and I am a little torn with the advice I want to give them.

 

 The tree is a great feature to their garden and they are keen to retain which I would also agree with. However there are a couple of concerning features to the tree that worry me slightly. 
 

 Firstly it is a co-dom stem which starts at ground level and separates at around 4m then the two stems also split in to other branches with very tight V shape unions.

 

 The tree has been there for 70 or so years (bit of a stab in the dark) I’d say and I have monitored it for the past 3/4 years with little change to its physical appearance. It have good vitality with a little bit of dead in the shaded inner crown which is to be expected. The tree was reduced by another company around 8 years ago and has reacted well to the reduction.

 

Target wise there are listed walls and neighbours which could be affected if something were to happen and also the customers have young children which always puts me on the more cautious side of things when giving advise or doing reports. 

 

 The other thing that I wasn’t 100% sure of is there seems to be white marks on the lower trunk which I would say is dead bits of bark unless there is a fungus I am completely unaware of. 
 

 I have said a re-reduction back to old points and a gentle lift will allow more light through to their garden and reduce the wind sail affect on the tree but wouldn’t really address the tight union issue.

 

 The twin stems have not joined or formed ridges which does concern me but this may be typical of ginkos (I’m not sure).

 

 The other idea I have toyed with would be a ridged brace through the two steams although in 17 years in the industry I have never done or suggested this to anyone. But I can’t see a static or dynamic brace in the crown stopping the failure that may occur between the two stems.

 

 I was just looking for a bit of input from some others on this and see if I can come up with a solution to the issue. 
 

 Photos below.

 

 Thanks in advance 👍

 

 

[Matthew Norman]

Co-dom stem with included bark and a heavily congested crown? I think your plan for a reduction and trunk bracing may give it a few more years, but ultimately these faults (or features) mean that no amount of remedial work can completely eliminate the risk of failure.

 

[Thesnarlingbadger]

Thank you Matthew,

 

 that was my thoughts on the situation. I guess a reduction and a rigid brace will retain the tree for another 10 years or so but I can’t see it winning this battle.

 I’ll relay this to my customers.

 

 Thank you for your input on this.

 

[Dan Maynard]

How long has it been split like that though? Surely a long time? Seems like one of those that isn't ideal, but is doing fine making it's own arrangements. 

[Dan Maynard]

I don't think I've seen enough ginko to judge really, but if it was a whitebeam you wouldn't be worried about that - take out every whitebeam with narrow forks there'd be none left.

[Thesnarlingbadger]

Hi Dan, 

 

 it’s not a split that I can tell of it’s just two codominant stems that have been growing together from early on. My worry is the two stems have not formed a union and are going to end up pushing each other apart. 
 

 Generally speaking the only Ginkos I see are singular stems and might have tight forks higher up which is why I am a little concerned with this one as there is a lot of weight and leverage above the base.

 

 If it was in the middle of a woodland of field I’d say leave it to its own devices but given the fact there are targets around I’m a little more concerned.

[AA Teccie (Paul)]

Just a few thoughts (not sure they'll help tho )

 

- the structural form of the tree 'is, what it is" and can't be changed, what it supports however can be.. (don't think I'd consider bracing the stem)

- don't know Ginkgo well enough to predict failure likelihoods but if it was N. Maple I'd fell it and if it was Beech I'd keep and monitor (be really useful to get a view here - my inclin is somewhere in between the two)

- would a phased reduction to a pollard(?) be an option, i.e. long-term reduction of the sail and maintenance of such (depends how committed the owners are to ongoing management)

- something of an aside, is there any possibility of direct-damage (lifting / distortion) to the stone wall...probably not, as looks substantial, but if its a 'listed wall', i.e. Conservation Area, it may factor in the proposals.

 

Pros n Cons...owners like likely influence and make the decision ultimately.

 

ATB

 

[Thesnarlingbadger]

11 hours ago, AA Teccie (Paul) said:

Just a few thoughts (not sure they'll help tho )

 

- the structural form of the tree 'is, what it is" and can't be changed, what it supports however can be.. (don't think I'd consider bracing the stem)

- don't know Ginkgo well enough to predict failure likelihoods but if it was N. Maple I'd fell it and if it was Beech I'd keep and monitor (be really useful to get a view here - my inclin is somewhere in between the two)

- would a phased reduction to a pollard(?) be an option, i.e. long-term reduction of the sail and maintenance of such (depends how committed the owners are to ongoing management)

- something of an aside, is there any possibility of direct-damage (lifting / distortion) to the stone wall...probably not, as looks substantial, but if its a 'listed wall', i.e. Conservation Area, it may factor in the proposals.

 

Pros n Cons...owners like likely influence and make the decision ultimately.

 

ATB

 

Hi Paul,

 

 Thank you.

 

 A phased reduction might just be the best option here as I know they are keen to retain it. 
 

 Could I ask why you would not consider a a ridged brace for this one? I have never done one or advised one from a consultancy point of view but would actually consider one here. Purely for the fact no other brace would do any good.

 

 I must admit my ginkgo knowledge is fairly limited when it comes to forks and bi-co stems but my thought process is it has been fine up until now and why worry, however as mentioned previously I panic a little when children enter the equation.

 

 There has been no impact on the wall thus far so I am not worried about this partially but it is a conservation area so if the tree were to have a hissy fit and drop one side then the damage could be fairly costly.
 

 What are your thoughts on the fact there doesn’t seem to be any sign of included bark or a ridge to stabilise the two stems?

 

 Thanks for your input, much appreciated. 

[AA Teccie (Paul)]

On 25/07/2024 at 20:18, Thesnarlingbadger said:

Hi Paul,
 

 Could I ask why you would not consider a a ridged brace for this one? I have never done one or advised one from a consultancy point of view but would actually consider one here. Purely for the fact no other brace would do any good.

Apologies for my delay in replying here:

If you're going to reduce the crown, and thereby reduce sail area and loading, and maintain it (reduced) I don't think rigid bracing is required - if the intention was to allow growth to continue then yes, brace it.

On 25/07/2024 at 20:18, Thesnarlingbadger said:

 What are your thoughts on the fact there doesn’t seem to be any sign of included bark or a ridge to stabilise the two stems?

Correspondingly there doesn't appear to be any...'separation', i.e. the union seems to be okay - I wished I knew Ginkgo better as a species to feel more confident in my views here but again, if the crown is reduced, and maintained ('reduced') it shouldn't be an issue I wouldn't have thought. 

[Treeation]

Id consider rigid bracing with matine grade stainless threaded rod through that bottom union and a light reduction/ or phased reduction to pollard (if tree looks like it can take it)....that's belts and braces - if they want to keep the tree surely that's the best option!

 

Wouldn't be a lot of work to/or great expense to do bracing (ISA do a great manual on propping/bracing) and just adds that extra safety margin which sounds important in this case. I can send you a picture of the relevant pages if you don't have the manual...