Kings Heath Park Trees

I’ve noticed these flowers, on my morning walk, just recently and wondered what they are. I haven’t noticed any leaves on the tree just yet – it is still only February.

Web searches have, so far, failed to produce any answers. The books I have that are guides to British trees don’t take into account that parks have all sorts of trees that are not native species. This may be one of them.

Any help in suggesting what the tree may be would be gratefully appreciated.