Also, Ernie Ball specifically recommends to NOT use lemon oil on their maple fretboards. Their boards are unfinished (at least, the non-Classic models). If the board is "finished", then there's no need to oil it at all. Just clean it occasionally.
Ernie Ball does recommend to use orange oil on their maple boards. And they recommend Murphy's Oil Soap for cleaning them. Murphy's has orange oil in it, if I recall correctly. So, for an unfinished maple board, Murphy's is your one stop shop for cleaning and conditioning your unfinished maple fret or finger board.