Heliantus decapetalus

Helianthus decapetalus
Photo by Dennis Kalma

Scientific Name:
Common Name:
ITIS Number:
NRCS Symbol:
  Helianthus decapetalus L.
Forest Sunflower
Asteraceae (Asters)

Plant: 60-150 cm tall; stems smooth to slightly rough

Flower: yellow; flower is actually a composite head of flowers with 8-15 yellow ray flowers around the edge and a central disk with yellowish to brownish flowers.

Leaves: opposite, entire, toothed; a pair of lower veins prominent and run paralell to the central vein, upper surface smoothish; leafstalks longer than 6 mm and have wings extending along them from the blade

Habitat: moist woods, streambanks, thickets

Similar Species: Helianthus divaricatus is very similar but has thicker leaves with very short leafstalks (less than 6 mm) and the stalks do not havve wings extending along them from the blade, the upper surface of the leaf is rough. The guidebooks make distinguishing between these two species sound easy - it is not. Many specimens seem to have intermediate characters.
Among other species Heliopsis helianthoides has more yellow ray flowers and the central disk flowers are browner; Rudbeckia hirta has lobed leaves and a button-like disk.