Actinoscirpus grossus(L.f.) Goetgh. & D.A.Simpson

Giant Bur Rush

WFO wfo-0000337413 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 6 observations

This species has been photographed under an open licence only 6 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Actinoscirpus grossus, photographed by Rongrong Angkaew
fig. a Rongrong Angkaew, CC BY 4.0 / 2021-04-26 / obs. 153431750
Actinoscirpus grossus, photographed by Rongrong Angkaew
fig. b Rongrong Angkaew, CC BY 4.0 / obs. 153935721
Actinoscirpus grossus, photographed by Oleg Kosterin
fig. c Oleg Kosterin, CC BY 4.0 / obs. 63231047
Actinoscirpus grossus, photographed by coenobita
fig. d coenobita, CC BY 4.0 / obs. 15025439
Actinoscirpus grossus, photographed by Oleg Kosterin
fig. e Oleg Kosterin, CC BY 4.0 / obs. 63231096
Actinoscirpus grossus, photographed by Oleg Kosterin
fig. f Oleg Kosterin, CC BY 4.0 / obs. 59157727
Actinoscirpus grossus, photographed by rjtizard
fig. g rjtizard, CC BY 4.0 / obs. 198286529
Actinoscirpus grossus, photographed by Oleg Kosterin
fig. h Oleg Kosterin, CC BY 4.0 / obs. 59157722

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 32 botanical countries

Regions where Actinoscirpus grossus is native: China South-Central, China Southeast, Hainan, Nansei-shoto, Ogasawara-shoto, Taiwan, Andaman Is., Assam, Bangladesh, Bismarck Archipelago, Borneo, Cambodia, East Himalaya, India, Jawa, Laos, Malaya, Myanmar, Nepal, New Guinea, Pakistan, Philippines, Solomon Is., Sri Lanka, Sulawesi, Sumatera, Thailand, Vietnam, West Himalaya, Northern Territory, Queensland, Western Australia China South-CentralChina SoutheastHainanTaiwanAssamBangladeshBismarck ArchipelagoBorneoCambodiaEast HimalayaIndiaJawaLaosMalayaMyanmarNepalNew GuineaPakistanPhilippinesSolomon Is.Sri LankaSulawesiSumateraThailandVietnamWest HimalayaNorthern TerritoryQueenslandWestern Australia Nansei-shotoAndaman Is.
Native distribution of Actinoscirpus grossus, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Andaman Is. AND ASIA-TROPICAL
Assam ASS
Bangladesh BAN
Bismarck Archipelago BIS
Borneo BOR
Cambodia CBD
East Himalaya EHM
India IND
Jawa JAW
Laos LAO
Malaya MLY
Myanmar MYA
Nepal NEP
New Guinea NWG
Pakistan PAK
Philippines PHI
Solomon Is. SOL
Sri Lanka SRL
Sulawesi SUL
Sumatera SUM
Thailand THA
Vietnam VIE
West Himalaya WHM
China South-Central CHC ASIA-TEMPERATE
China Southeast CHS
Hainan CHH
Nansei-shoto NNS
Ogasawara-shoto OGA
Taiwan TAI
Northern Territory NTA AUSTRALASIA
Queensland QLD
Western Australia WAU

Not drawn on the map: Ogasawara-shoto. We hold no public-domain boundary for this region, so it is 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.

Where it actually grows measured, from 67 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low 10.9 °C 21.6 °C 24.6 °C
Warmest month, mean daily high 28.9 °C 32.1 °C 35.4 °C
Annual rainfall 1,210 mm 2,170 mm 3,078 mm
Rainfall in the driest quarter 22 mm 135 mm 550 mm

It is not found anywhere that gets close to freezing. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 67 research-grade observations of Actinoscirpus grossus that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 16 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.

  • Hymenochaeta grossa (L.f.) Nees
  • Hymenochaeta haematodes Nees & Meyen
  • Hymenochaeta maxima (Roxb.) Nees
  • Isolepis maxima A.Dietr.
  • Rhynchospora kysoor (Roxb.) A.Dietr.
  • Schoenoplectus grossus (L.f.) Palla
  • Scirpus aemulans Steud.
  • Scirpus canaliculatotriqueter Steud.
  • Scirpus griffithii Boeckeler
  • Scirpus grossus L.f.
  • Scirpus grossus f. kysoor (Roxb.) Beetle
  • Scirpus grossus var. kysoor (Roxb.) C.B.Clarke
  • Scirpus kysoor Roxb.
  • Scirpus kysoor Roxb.
  • Scirpus maximus Roxb.
  • Scirpus scaberrimus Boeckeler

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.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. 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.