This plant is a taprooted perennial herb producing rough-haired stems usually one to three meters tall.
The leaves are variable in shape and size, being 4 to 60 cm (1 ¹⁄₂ to 23 ¹⁄₂ in) long and 1 to 30 cm (¹⁄₂ to 11 ³⁄₄ in) wide.
They are hairy, smooth-edged or toothed, and borne on petioles or not.
The back of the flower head has layers of rough, glandular phyllaries.
The head contains 27 to 38 yellow ray florets and many yellow disc florets.
The fruit is a cypsela which can be almost 2 cm (³⁄₄ in) long and is tipped with a pappus of two short awns.
This plant is a taprooted perennial herb producing rough-haired stems usually one to three meters tall. The leaves are variable in shape and size, being 4 to 60 cm (1 ¹⁄₂ to 23 ¹⁄₂ in) long and 1 to 30 cm (¹⁄₂ to 11 ³⁄₄ in) wide. They are hairy, smooth-edged or toothed, and borne on petioles or not. The back of the flower head has layers of rough, glandular phyllaries. The head contains 27 to 38 yellow ray florets and many yellow disc florets. The fruit is a cypsela which can be almost 2 cm (³⁄₄ in) long and is tipped with a pappus of two short awns.
Silphium laciniatum