Not to my knowledge, to me they look mostly the same, white buoy, mostly with a blue stripe as required by the state but sometimes not.
Owners will sometimes identify their ball with the word "private" in large black letters, and are also required to have the DNR permit number displayed (i.e. 28-12345). State park buoys may or may not have the fee and registration instructions stickered on the side.
All of this presumes weather or maintenance neglect have not deteriorated one or the other.