Spider wrote in :

I note you're no longer in SE London. I wonder where you are, just in
case it informs your gardening .. or our understanding of it.
Do let us know what you decide to do.
Best wishes,

Hi Spider,
Thanks for the added input. I'll leave the tree as it is for now, but will
keep my eye open for a possible alternative. Your Hawthorn tree might end
up too tall for my purposes. I'm loking for something that grows to about 4
metres in height, max, ideally with no low branches, but a good spread and
dense foilage up top! That's the ideal, anyway. I live down on the south
coast of the west country now, so I get a fair bit of wind, very little
frost, and have salty air and alkaline, clayey soil.

I'm trying to think where there is 'high ground' in SE London! I remember
Blackheath Hill which was right on my doorstep in 1980, and also Crystal
Palace, which I could see in the distance from my window, which seemed to
be on a hill but can't remember much else in the way of hills in that
segment of London.

Best regards,
Al