On Apr 10, 9:20*pm, "Jo" wrote:
Whilst looking at a neighbour's pink blossom tree today I noticed that one
very large thick branch had produced white blossom of a completely different
shape and size to the pink blooms on all the other branches. *A bit of a
mystery. *Can anyone explain how this can happen?

Sounds to be like it's a grafted tree, and the rootstock has thrown up
a sucker which has developed and is now flowering with white flowers
whilst the origional plant is pink.
I've seen this a few times with the Purple Leaved Plum where the
sucker is green leafed, it looks rather good if the balance is about
equal.
David Hill