Osmunda japonicaThunb.

WFO wfo-0000750727 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Osmunda japonica, photographed by Agnes Trekker
fig. a Agnes Trekker, CC0 1.0 / 2021-10-24 / obs. 165534213

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.

The specimen a real sheet, in a real collection

Herbarium
Royal Botanic Gardens, Kew
Accession
K001057752
Filed as
Osmunda japonica Thunb.
Det. by
Fraser-Jenkins, C.R.
Collected
s.coll. 1821-01-01
Origin
NP
The sheet
View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 18 botanical countries

Regions where Osmunda japonica is native: China North-Central, China South-Central, China Southeast, Japan, Korea, Kuril Is., Nansei-shoto, Sakhalin, Taiwan, Tibet, Assam, East Himalaya, Myanmar, Nepal, Pakistan, Thailand, Vietnam, West Himalaya China North-CentralChina South-CentralChina SoutheastJapanSakhalinTaiwanTibetAssamEast HimalayaMyanmarNepalPakistanThailandVietnamWest Himalaya KoreaNansei-shoto
Native distribution of Osmunda japonica, 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
China North-Central CHN ASIA-TEMPERATE
China South-Central CHC
China Southeast CHS
Japan JAP
Korea KOR
Kuril Is. KUR
Nansei-shoto NNS
Sakhalin SAK
Taiwan TAI
Tibet CHT
Assam ASS ASIA-TROPICAL
East Himalaya EHM
Myanmar MYA
Nepal NEP
Pakistan PAK
Thailand THA
Vietnam VIE
West Himalaya WHM

Not drawn on the map: Kuril Is.. 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 833 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -9.1 °C 0.7 °C 9.8 °C
Warmest month, mean daily high 19.3 °C 27.3 °C 30.9 °C
Annual rainfall 1,346 mm 2,156 mm 4,424 mm
Rainfall in the driest quarter 81 mm 246 mm 775 mm

It is found where winters bring hard frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 833 research-grade observations of Osmunda japonica 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 13 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.

  • Osmunda biformis (Benth.) Makino
  • Osmunda biformis var. divisa (Makino) Makino
  • Osmunda japonica f. divisa (Makino) Tagawa
  • Osmunda japonica var. divisa (Makino) Nakai
  • Osmunda japonica var. sublancea (Christ) Nakai
  • Osmunda regalis f. divisa Makino
  • Osmunda regalis subsp. japonica (Thunb.) Á.Löve & D.Löve
  • Osmunda regalis var. biformis Benth.
  • Osmunda regalis var. japonica (Thunb.) Milde
  • Osmunda regalis var. sublancea Christ
  • Osmunda speciosa Wall. ex Hook. & Grev.
  • Osmunda speciosa Wall.
  • Osmundastrum japonicum C.Presl

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. 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.