I've come across this problem before and been able to track down the offending mod and therefore find the missing mesh, but I'm stuck this time.

For some reason, FormID crashes whenever I try to use it, so this is the info from Refscope:-

Reference 0016F7BA
(Non-Persistent)
Defined in Oblivion.esm

Static 0001C8C6
Defined in Oblivion.esm

Because it's in oblivion.esm itself, I don't really know how to proceed, so any advice would be very welcome.

0001C8C6 is form "LandscapeLogOak02". If you have any mods that are supposed to be changing this mesh to a different one, try de-activating them. Otherwise, use TES4Edit to search your mods and find which one is modifying this form.

Thanks, Khettienna, I'll check that out.

What's got me is I can't think of anything that would changes such a mesh.

But on second thoughts, it could be from either OWC ND or Cyrodiil Upgrade Resource Pack.

Nevertheless, you have shown me how to track it down - thanks again.