Hemizonia congestaDC.

Hayfield Tarweed

WFO wfo-0000033424 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Hemizonia congesta, photographed by Cricket Raspet
fig. a Cricket Raspet, CC BY 4.0 / 2022-05-07 / obs. 196211104
Hemizonia congesta, photographed by joergmlpts
fig. b joergmlpts, CC BY 4.0 / obs. 204725320
Hemizonia congesta, photographed by Alexander Wentworth
fig. c Alexander Wentworth, CC BY 4.0 / obs. 196364442
Hemizonia congesta, photographed by Steve Woodward
fig. d Steve Woodward, CC0 1.0 / obs. 191165886
Hemizonia congesta, photographed by Dominic Gentilcore
fig. e Dominic Gentilcore, CC BY 4.0 / obs. 202364989
Hemizonia congesta, photographed by Daniel Das
fig. f Daniel Das, CC0 1.0 / obs. 168553814
Hemizonia congesta, photographed by rappman
fig. g rappman, CC BY 4.0 / obs. 169253950
Hemizonia congesta, photographed by George Williams
fig. h George Williams, CC BY 4.0 / obs. 173087680

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.

Flowering n = 2,731 observations

Peak flowering in Sep, from 2,731 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 25 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.

  • Hemizonia calyculata (Babc. & H.M.Hall) D.D.Keck
  • Hemizonia citrina Greene
  • Hemizonia clevelandi Greene
  • Hemizonia congesta subsp. leucocephala (Tanowitz) D.J.Keil
  • Hemizonia congesta subsp. vernalis (D.D.Keck) Tanowitz
  • Hemizonia congesta var. calyculata (Babc. & H.M.Hall) Jeps.
  • Hemizonia congesta var. congesta
  • Hemizonia congesta var. lutescens (Greene) Jeps.
  • Hemizonia congesta var. luzulifolia (DC.) Jeps.
  • Hemizonia congesta var. tracyi (Babc. & H.M.Hall) Jeps.
  • Hemizonia leucocephala Tanowitz
  • Hemizonia lutescens (Greene) D.D.Keck
  • Hemizonia luzulifolia DC.
  • Hemizonia luzulifolia subsp. luzulifolia
  • Hemizonia luzulifolia subsp. rudis (Benth.) D.D.Keck
  • Hemizonia luzulifolia subsp. tracyi Babc. & H.M.Hall
  • Hemizonia luzulifolia var. citrina (Greene) Jeps.
  • Hemizonia luzulifolia var. lutescens Greene
  • Hemizonia luzulifolia var. luzulifolia
  • Hemizonia multicaulis Hook. & Arn.
  • Hemizonia multicaulis subsp. multicaulis
  • Hemizonia multicaulis subsp. vernalis D.D.Keck
  • Hemizonia sericea Hook. & Arn.
  • Hemizonia tracyi (Babc. & H.M.Hall) D.D.Keck

and 1 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.