Family: Asteraceae
giant sunflower, swamp sunflower, tall sunflower
[Helianthus alienus E.Watson, more...]
Merel R. Black
Merel R. Black
University of Wisconsin - Madison (WIS-VP)
Etymology: Helianthus: derived from two Greek words helios, "sun," and anthos, "flower," in reference to the sunflower's supposed tendency to always turn toward the sun
Plants: erect, perennial, 3'-10' tall forb; stems usually with spreading hairs but sometimes hairless, often purplish
Leaves: opposite on the lower stem, upper alternate, flat, narrow, at least 3 times as long as wide, upper surface rough, lower with long hairs
Flowers: head 1 3/4"- 3 1/4" wide with 10-20 yellow rays, yellow disks, hairy bracts (phyllaries) long and loose; inflorescence in loose clusters of several to many heads on stalks less than 4" long; blooms July-Oct.
Habitat: moist; forests, swamps
Plants: erect, perennial, 3'-10' tall forb; stems usually with spreading hairs but sometimes hairless, often purplish
Leaves: opposite on the lower stem, upper alternate, flat, narrow, at least 3 times as long as wide, upper surface rough, lower with long hairs
Flowers: head 1 3/4"- 3 1/4" wide with 10-20 yellow rays, yellow disks, hairy bracts (phyllaries) long and loose; inflorescence in loose clusters of several to many heads on stalks less than 4" long; blooms July-Oct.
Habitat: moist; forests, swamps
Floristic Rating: Coefficient of Conservatism = 4, Wetland Indicator = FACW 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 USDA Agricultural Research Service (ARS): Images of seeds, fruits, embryos, etc.
Merel R. Black
Merel R. Black
Janice Stiefel
Matthew L. Wagner
Matthew L. Wagner
Janice Stiefel
Robert Bierman
Kenneth J. Sytsma
Christopher Noll
Merel R. Black
Merel R. Black
Matthew L. Wagner
Matthew L. Wagner
Matthew L. Wagner
Caroline A. Creevey
