It's a cherry tree. Blossoms really nice. I've put a couple of pictures in here a few months ago
I wouldn't mind keeping the tree though. The garden is more than big enough for what I'll ever do with it and it provides some privacy, even though we back on to train tracks. Only my 80 year old neighbour can see me sunbathing In shorts in the summer and she is out most of the time.
I'm not totally positive, but it could be
Honey Fungus in which case it's just a matter of time before it dies.
We had it here on a beautiful large and old Labernum and the tree died within 2 years. When I cut the tree down after it ceased to grow leaves one year, some of the growth rings inside the wood were blackened and sections of the inside of the bowl had just rotted away, pretty nasty stuff, and the really bad news is I understand the fungus can lurk in the ground for many years later condemning anything else you plant on the spot. Eradication of it can be difficult. Sarge may know more about it.
I'm not sure about Cherries, but we also had two of them years ago in the garden, mature ornamentals and very pretty, but they both decided to die within the space of a few years with what we now suspect might have also been Honey Fungus too though I was told at the time that some species of ornamental don't live too long anyway, perhaps as little as 25 years. Their bark seems to split and let in all kinds of nasty stuff.