Silphium laciniatum (Compass Flower, Compass Plant or Rosinweed) is a species of flowering plant in the genus Silphium. It is native to east-central North America, from southern Ontario and New York south to Alabama and west across the prairies to North Dakota and Colorado south to Texas.

Growth
It is a perennial herbaceous plant similar in appearance to a sunflower, growing to 1-4 m tall, with bristly-hairy stems. The leaves are alternately arranged, and deeply pinnately lobed; the basal leaves up to 40 cm long, becoming smaller higher up the stem. The flowers are produced in flowerheads (capitula) 5-12 cm diameter, with a ring of ray florets surrounding the 2-3 cm diameter center of disc florets. Flowering is in late summer, typically from July to September.

Characteristics
Compass plants are so named because they tend to align their foliage East-West to present the minimum surface area to the hot noon sunshine. The taproot of the compass plant may grow to more than 9-14 ft. deep, making it hardy and resistant to drought.

Medicinal uses
The plant was used in Native American herbal medicine as a vermifuge, and to treat coughs and asthma.