Stiff Sunflower

Helianthus pauciflorus

"Helianthus pauciflorus", called the stiff sunflower, is a North American plant species in the sunflower family. It is widespread across the Great Plains, the Rocky Mountains, and the Great Lakes region, and naturalized in scattered locations in the eastern United States and in much of southern Canada.
Helianthus pauciflorus Helianthus pauciflorus (Stiff Sunflower) showing imbricate bracts. Leaves on these plants are oblong-lanceoleate (roughly 5 times longer than wide) with acuminate tips so Helianthus pauciflorus ssp. pauciflorus? Geotagged,Helianthus pauciflorus,Stiff sunflower,Summer,United States

Appearance

Stiff sunflower is a perennial herb 50–200 cm tall, spreading by means of underground rhizomes. Most of the leaves are attached near the bottom of the stem. One plant can produces 1-10 flower heads, each head with 10-20 yellow ray florets surrounding at least 75 red or yellow disc florets.
Helianthus pauciflorus Part of a small colony growing in thin soil over metagraywacke bedrock. Geotagged,Helianthus pauciflorus,Stiff Sunflower,Summer,Sunflower,United States

Naming

Hybrids between "H. pauciflorus" and "H. tuberosus" are known as "H." × "laetiflorus". The name "H. laetiflorus" has also been used as a synonym of "H. pauciflorus".

Subspecies:
⤷  "Helianthus pauciflorus" subsp. "pauciflorus": 80–200 cm tall; leaves alternate near the end of the stem, 8–27 cm long, with tips acuminate.
⤷  "Helianthus pauciflorus" subsp. "subrhomboideus" O.Spring & E.E.Schill.: 50–120 cm tall; leaves opposite, 5–12 cm long, with acute or obtuse tips.

References:

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Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderAsterales
FamilyAsteraceae
GenusHelianthus
SpeciesH. pauciflorus
Photographed in
United States of America