ring barked sycamore mystery

[Ali Gunner]

I know of a small (approx 30 - 40 cm diameter) sycamore that was completely ring barked by deer about 10 years ago. The ring barking is at least a metre wide and extends right around the trunk - there are no strips of bark left. The wood of the tree where it is ring barked has become quite riddled with beetle holes.

And yet..... the tree has continued to flourish and has produced a very healthy crown every year for the past 10 years........ !!!

anyone got any ideas how this happens?

Ali Gunner

[coasty]

If the deer have only removed the Bark and not the layer in from there then the tree will remain able to continue transmitting fluids through the layers which are beneath that.
The bark layer is actually dead cells, and apart from protecting the inner layers does not transmit nutrients etc, The inner layers that transmit moisture are the cambium layers if these have remained intact then the tree will continue to grow.

[Thunderbird+]

Hi I've also seen trees like this that appear to be completely ring-barked which have managed to survive on their sap reserves for an astonishing 2-3 years but not as long as 10! therefore the theory i'd like to put forward is that the damage caused by the deer took place over a long period of time and only became completely ring barked more recently.
My other theory is that, small shreds of the cambrium layer remained intact giving just a spark of life to keep the tree ticking over.
What ever the reason, it sounds like one of those amazing trees that seems to cling onto life to the bitter end. when I look at some of the old veteran trees like church yard yews that in many cases pre-date the church itself I often wonder how they have survived for so long, when we see much younger trees dieing from pests and diseases. I guess we will always find remarkable exeptions to the rule!
BTW Welcome! Tbird+

[nuttyarb]

Hi all.
Is the tree next to other sycamores? If so, root grafting is possibly the answer...

[Frimsley]

Not sure how root grafting would help the situation Nuttyarb. The roots could graft as much as they like, the crown that flourishes is still isolated from them.

I favour the intact cambium idea. The bad news is that one of the jobs of the bark is to protect the cambium, particularly from dessication. I've seen such trees keep going for a few years, but eventually they succumb and the crown dies.

[Dan Salter]

Can i point out its a SYCAMORE!!!?....

I'd be concerned if it was a native Oak or something....

[nuttyarb]

Hiyah Frimsley. The intact cambium is probably the right answer- but only if the stem is fluted so that the cambium can be protected from grazing animals.
The idea behind the root grafting is that water- and therefore nutrients- can still be transported in the xylem and symplast. The tree will be able to support a crown as food can still be produced and stored in the branches and twigs.
The problem for the tree is that food cannot be transported down to the roots, due to the loss of the phloem. This is where the root grafting comes in- the tree can get food from other trees root systems to feed its own roots.
As long as water and nutrients can travel up to the crown, a tree may be able to survive in this way.

Hey Dan- it may be a sycamore, but it is an interesting conundrum nonetheless!