Silphium is a genus of North American plants in the tribe Heliantheae within the family Asteraceae.

[1][2] Members of the genus, commonly known as rosinweeds, are herbaceous perennial plants growing to 0.2 m (8 in) to more than 2.5 m (8 ft 2 in) tall, with yellow (rarely white) flowerheads that resemble sunflowers.

In the rosinweeds, the ray florets in the head are female and the disc florets are male;[3] this differs from sunflowers, where ray florets are sterile and disc florets are perfect, capable of producing both pollen and seeds.

[4] 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.

[3] Species in the genus include:[5][3][6][7][8][9] Numerous species are now regarded as members of the genera Berlandiera and Verbesina.