White Milkweed, a native species, has been added to the USWildflowers database (06/07/2010.)  Scientific name is Asclepias variegata.  This plant also also goes by the common names Variegated Milkweed, and Redring Milkweed – which is the USDA National Common Name for the plant.

White Milkweed – Asclepias variegata