cliff_the_gardener wrote:
It is very possible to graft onto a trunk by a process known as
topworking and the graft technique is done by cleft grafting.

Cliff, thank you so much for this. I have done some grafting a few
times (Lancaster's Middlewood and during a C and G course, but only on
'twig' size. I never thought I could do it on an older tree. I'm
emailing you with a couple of questions - I fancy moving the tree and
then grafting, it could be my winter project. Thanks again.