"Silphium is a genus of about 20 species of flowering plants in the family Asteraceae, native to eastern North America. Members of the genus, commonly known as Rosinweeds, are herbaceous perennial plants growing to 0.5–4 m tall, with yellow (rarely white) flowerheads. The name of the genus comes from the Ancient Greek word for a North African plant whose identity has been lost, though it is known its gum or juice was prized by the ancients as a medicine and a condiment."
Taken from wikipedia's page at:
http://en.wikipedia.org/wiki/S...
