What causes this?

[Hodge]

What causes this? At the top of the hollow trunk there was a cavity where it looks like a bow has ripped off along time ago, would water filling the cavity and sitting there cause it? It's right down into the centre of the root plate too.

[Goaty]

Looking at top pic its only the heartwood not the living sapwood. You can just see a slither of heartwood in that picture. I assume its because the living wood pushes life in nutrients and water around, whereas the heartwood is static and just absorbs and decays downwards from point of entry, then anerobic activity takes over.

Thats only my theory. Im just working class. A biologist may come along soon.

[Hodge]

Looking at top pic its only the heartwood not the living sapwood. You can just see a slither of heartwood in that picture. I assume its because the living wood pushes life in nutrients and water around, whereas the heartwood is static and just absorbs and decays downwards from point of entry, then anerobic activity takes over.

Thats only my theory. Im just working class. A biologist may come along soon.

 

So in laymans terms the water has sat there and rotted the heart wood away??

[Graham]

Looks like an aerial root has formed in the cavity to take advantage of nutrients in the decay.

[treeseer]

Looks like an aerial root has formed in the cavity to take advantage of nutrients in the decay.

Yes quite vigorously as well. These pics from austin tx, Ulmus crassifolia was half-felled when i pulled up to the hotel. No reason to it at all; sapwood very healthy. i hope the aerial rooting shows up.