Synonym:  Rudbeckia serotina  Nuttall

              

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Plants of fields, roadsides, open disturbed areas; more often on dry soils.  Flowers July to August.  Introduced.

Our plants are:  Rudbeckia hirta  L.  var.  pulcherrima  Farwell...

Biennial or short-lived perennial.  Usually fibrous-rooted.  Stems may be solitary or several, densely pubescent, with long, spreading, somewhat bristly hairs. Typical height is 1.5 to 2.5 feet.

Inflorescences consist of from 1 to 5 flower heads (per stem) on long peduncles.  Peduncles can be up to 1/3 of total plant height.

Flower heads are radiateRay florets are neuter, bright yellow to yellow-orangeDisc florets are bisexual and fertile.  Receptacles are obconical in shape, beset with numerous, dark brown, sharp-pointed scales, called "chaff".  Scales subtend individual disc florets, partially obscuring them.  The visible portion of the disc florets is dark brown.  Involucral bracts are herbaceous (green/leafy), lance-linear, densely pubescent.

Basal leaves may be present at flowering, dependent on availability of moisture.  Stem leaves are elliptic, lanceolate or oblanceolate; densely pubescent; unlobed, with untoothed margins or shallowly toothed.

Cypselae are black, flat-topped, 4-angled; without pappus.

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Similar species:  Helenium flexuosumRudbeckia triloba is similar to R. hirta, but its flower heads are smaller, with shorter rays and  lobed leaves.  R. triloba is mostly an introduced garden species.  Variety hirta is considered historic in NY.  It is distinguished by broader basal leaves, and leaves generally that are coarsely toothed.

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