Haven't followed the urg thread but have followed postings here...

Yes, Ivy does develop aerial roots - those are the short sticky-out coarsely
hairy bits on the climbing stems - but they don't take sustenance directly
from the supporting tree. If the Ivy comes across a pocket of soil in the
course of its climbing, for instance in a fork or poll, the roots will
develop and take advantage of it. I doubt very much whether this would ever
be enough to support a large crown of ivy once the land roots had gone.

It can cause local bark damage - tree surgeons seem to disagree about how
serious this is - but I don't know of any evidence it poisons its support.
As others have said, the main threat is the weight causing overthrow in
windy conditions.

Ivy of course has a lot of wildlife value of its own but it can be a threat
to other things, such as rare corticolous lichens.

BTW forms of Ivy prevalent along SW and W coasts, known as 'Atlantic Ivy' or
ssp. hibernica, are mostly not much cop at climbing trees.


"Mike" wrote in message
...
In article , Paul
England writes
Does anyone know if mature ivy develop aerial roots when attached to
trees ?
My farm labourer neighbour, had to pull down a 50 yr old, ivy strangled
oak.
He said it wasn't worth severing the base of mature ivy, for the above
reason.
What does the team think ?

Regards ... Paul


Been quite a hefty and interesting thread on uk.rec.gardening on this
very subject.

What was the verdict urglers?

x posted to uk.rec.gardening for response.


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in one
pretty and well preserved piece, but to skid across the line broadside,
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