Wizards and witches came to be from an evolutionary branch from humans,
but even though they had magic, they didn't know it.
Until one day some
one picked up some magic grass and shot a spell.
It shot through a tree
and made a clean hole as smooth as a rock.
From then on to test if you
held magical abilites they made you pick up a piece of magic grass and
see if you were part of the small magical species. (fun fact the first wands
were blades of grass)