There seems to be much confusion about ivy. I'm not sure that I want to go
into all the details and explain it all to those who don't understand, but I
think it's enough to point out that to be a scavenger you have to be able to
recognise that something's dead, and that it can therefore be 'scavenged'.
Plants (including ivy) are unable to make this distinction. Put simply, plants
don't 'think' in the way we recognise that animals can.

Dave.

Dave.