Milk thistle, also known as Blessed Milk Thistle and Mary Thistle, is a
member of the aster family that is native to the Mediterranean region and
now naturalized throughout the world.
The plant's species name (marianum)
and many of its common names reference the Virgin Mary because the white
mottling that appears on the leaf is said to be made by her tears.
For
thousands of years, the ripe seeds have been harvested to make infusions and
extracts.