Plate 1 figs. a–h · 8 separate observations
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.
Native range 151 botanical countries
Not drawn on the map: Socotra, Kazan-retto, Ogasawara-shoto. We hold no public-domain boundary for these regions, so they are listed rather than guessed at.
Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.
Flowering 206 in flower of 253 examined
Peak flowering in Dec. Each bar is the share of Cyperus rotundus observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 206 of 253 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.
Also published as 77 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.
- Chlorocyperus rotundus (L.) Palla
- Cyperus agrestis Willd. ex Spreng. & Link
- Cyperus badius var. inconspicuus (Nyman) Nyman
- Cyperus bicolor Vahl
- Cyperus bulbosostoloniferus Miq.
- Cyperus comosus Sm.
- Cyperus elongatus Sieber ex Kunth
- Cyperus herbicavus Melliss
- Cyperus hexastachyos Rottb.
- Cyperus hildra Poir.
- Cyperus hydra Michx.
- Cyperus inconspicuus Gennari
- Cyperus laevissimus Steud.
- Cyperus leptostachyus Griff.
- Cyperus longus Boeckeler
- Cyperus merkeri C.B.Clarke
- Cyperus micreilema Steud.
- Cyperus nubicus C.B.Clarke
- Cyperus ochreoides Steud.
- Cyperus officinalis Nees ex Godr.
- Cyperus oliganthus Gand.
- Cyperus olivaris O.Targ.Tozz.
- Cyperus olivaris var. brevibracteatus Le Grand
- Cyperus pallescens Poir.
and 53 more.
Sourcesevery claim on this page
- World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
- iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
- Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
- Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.
We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.