Rudbeckia hirtaL.

black-eyed Susan

WFO wfo-0000027627 Accepted WFO 2026-06 8 photographs CC0 / CC BY In the accuracy benchmark

Plate 1 figs. a–h

Rudbeckia hirta, photographed by Ryan Sorrells
fig. a Ryan Sorrells, CC BY 4.0 / 2022-06-11 / obs. 205634473
Rudbeckia hirta, photographed by Taro Ietaka
fig. b Taro Ietaka, CC BY 4.0 / obs. 205459716
Rudbeckia hirta, photographed by mefisher
fig. c mefisher, CC0 1.0 / obs. 205023572
Rudbeckia hirta, photographed by Rebecca Gimenez Husted
fig. d Rebecca Gimenez Husted, CC BY 4.0 / obs. 205823508
Rudbeckia hirta, photographed by Scott Allen Davis
fig. e Scott Allen Davis, CC BY 4.0 / obs. 205101818
Rudbeckia hirta, photographed by Jay Pruett
fig. f Jay Pruett, CC BY 4.0 / obs. 204299101
Rudbeckia hirta, photographed by Jay Pruett
fig. g Jay Pruett, CC BY 4.0 / obs. 204300508
Rudbeckia hirta, photographed by mefisher
fig. h mefisher, CC0 1.0 / obs. 205015435

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Confused withby our own model

These are not lookalikes we guessed at. Each one is a species our identification model genuinely mistook for this plant, and how many times. The error rate is published.

Flowering n = 21,866 observations

Peak flowering in Jul, from 21,866 community-annotated observations worldwide. This is a global aggregate, not a forecast for your garden: the same species flowers on different dates in different hemispheres, and citizen-science records cluster near cities, at weekends, and in spring. Where a species has fewer than 30 annotated records we do not draw this chart at all.

Also published as 58 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Centrocarpha gracilis D.Don ex Sweet
  • Centrocarpha gracilis (Nutt.) D.Don ex G.Don
  • Centrocarpha hirta D.Don ex Sweet
  • Centrocarpha hirta (L.) D.Don ex G.Don
  • Coreopsis hirta Raf.
  • Helianthus hirtus (L.) E.H.L.Krause
  • Rudbeckia amplectens T.V.Moore
  • Rudbeckia bicolor Nutt.
  • Rudbeckia brittonii Small
  • Rudbeckia divergens T.V.Moore
  • Rudbeckia flava var. perbracteata Lunell
  • Rudbeckia flexuosa T.V.Moore
  • Rudbeckia floridana T.V.Moore
  • Rudbeckia floridana var. angustifolia T.V.Moore
  • Rudbeckia floridana var. floridana
  • Rudbeckia gracilis Nutt.
  • Rudbeckia hirta f. dichrona Clute
  • Rudbeckia hirta f. flavescens Clute
  • Rudbeckia hirta f. frondosa Clute
  • Rudbeckia hirta f. gigantea Clute
  • Rudbeckia hirta f. hirta
  • Rudbeckia hirta f. homochroma Steyerm.
  • Rudbeckia hirta f. pleniflora Moldenke
  • Rudbeckia hirta f. viridiflora Burnham

and 34 more.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.

We publish what we can source and we say so when we cannot. This page has no care advice, no toxicity claim and no native range, because we do not yet have those from a source we can cite.