Etymology: Silphium: old Greek generic name referring to resinous juice
Plants: erect, perennial, 3'-8' tall forb; stems square in X-section, mostly smooth
Leaves: opposite, strongly toothed, upper and lower leaves about the same size, surrounding the stem to form a cup
Flowers: head 1 3/4"- 2 3/4" wide with 16-35 (usually 21 or 34) yellow rays 1/2"-1 1/2" long, disk 1/2"-1" wide; inflorescence of several heads in an open, branched cluster; blooms July-Sept.
Fruits: dry seed with no fluffy pappus
Habitat: full to partial sun; wet to moderate moisture; prairies, woods, streambanks; in sandy, loamy soil
Conservation Status: Native
Plants: erect, perennial, 3'-8' tall forb; stems square in X-section, mostly smooth
Leaves: opposite, strongly toothed, upper and lower leaves about the same size, surrounding the stem to form a cup
Flowers: head 1 3/4"- 2 3/4" wide with 16-35 (usually 21 or 34) yellow rays 1/2"-1 1/2" long, disk 1/2"-1" wide; inflorescence of several heads in an open, branched cluster; blooms July-Sept.
Fruits: dry seed with no fluffy pappus
Habitat: full to partial sun; wet to moderate moisture; prairies, woods, streambanks; in sandy, loamy soil
Conservation Status: Native
Flora of North America: Flora of North America Floristic Rating: Coefficient of Conservatism = 4, Wetland Indicator = FACW- Wisconsin Natural Resources Magazine: Information and Photos Atlas of the Wisconsin Prairie and Savanna Flora: by T.S. Cochrane & H.H. Iltis: habitat, distribution infomation / flowering and fruiting times USDA Plants Database: Federal Distribution and detailed information including photos Dan Tenaglia's The Missouri Flora: Fabulous photographs; detailed descriptions; color and leave arrangement key. David G. Smith's "Delaware Wilflowers": Beautiful photographs; descriptions Illinois Wildflowers: Wonderful photographs; detailed descriptions; color and leaf arrangement key Southwest School of Botanical Medicine: Britton & Brown Illustrated Flora - 2nd Edition (1913) "An Illustrated Flora of the Northern United States and Canada"
Matthew L. Wagner
Paul Drobot
Matthew L. Wagner
John M. Schoeneker
Stephen L. Solheim
Matthew L. Wagner
Matthew L. Wagner
Paul Drobot
Paul Drobot
Christopher Noll
Stephen L. Solheim
Matthew L. Wagner
Elizabeth Rogers
Paul Drobot
Stephen L. Solheim
Robert W. Freckmann
Elizabeth Rogers
Botanical Illustration
