In message , Chris Hogg
writes
On Tue, 7 Jun 2016 20:59:01 +0100, Ian Jackson
wrote:

A 60 foot ash tree (just outside the end of my back garden) was suddenly
killed by ivy.

One spring, it had just started to come into leaf, when I noticed they
were withering. I found that the ivy which had been growing up it had
got under the bark (a few feet off the ground), and lifted it -
effectively ring-barking it.

Did the ivy lift the bark, or was the bark already lifting and the ivy
just grew into the space?

I can't be certain. but the bark was thick, gnarly and 'corky'.

I ask, because I have a substantial Olearia
Traversii that is dying and the bark is lifting at the base of the
trunk, but there's no ivy there causing or helping it to lift. It's
diseased.

The tree wasn't visibly diseased. Most likely the ivy just got into some
cracks in the bark.
--
Ian