A young field maple would be my suggestion - often used as a hedge plant. Happy to be proved wrong as the leaves look more serrated than normal.

I think it might be Acer brilliantissimum - the newer leaves are the paler ones, and they go greener over time. Good autumn colour too. Google for images, but most of the pics show it in its spring foliage (bright and pale) or its autumn turning...

Is that the one whose first leaves are a bit pinkypeachy?

Yes Pam, particularly the new leaves.

Properly Acer pseudoplatanus ' Brilliantissimum', for ease of looking up. : )