Posted: 27/12/2015 at 11:02
Hi Tony, It looks like it might be a cherry tree of some kind. With the different appearance of the lower and upper trunk, it looks like it has been grafted and the graft has failed, very probably by being infected with bacterial canker:
As you can see from the RHS advice above, there is now no treatment available so the best course of action would be to replace the tree, unfortunately. Even if Bordeaux Mixture were available, a lesion on the main trunk like this would not respond.