It is native to the western United States, including the Pacific Coast and possibly as far east as the Rocky Mountains, depending on which populations are treated as part of the species.

This native thistle is a perennial herb growing up to about 1.5 meters tall.

The inflorescence is made up of clustered flower heads which are lined with spiny phyllaries.

The head is filled with white or purple flowers up to 2.5 centimeters long.

The fruit is an achene a few millimeters long topped with a pappus up to about 2 centimeters in length.