That is the million dollar question, indeed...So the question is, it it http://en.wikipedia.org/wiki/Acer_pseudoplatanus
or is it http://en.wikipedia.org/wiki/Platanus_occidentalis
In Europe (or the USA), you will also often find http://en.wikipedia.org/wiki/London_plane_tree referred to as sycamore.
I blame the guys who discovered all these tree breeds, should have given them all crazy names so it'd be easier to tell 'em apart!
