Juncus ranariusSongeon & E.P.Perrier

seasice rush

WFO wfo-0000777150 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 5 observations

This species has been photographed under an open licence only 5 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.

Juncus ranarius, photographed by Amy Huie
fig. a Amy Huie, CC BY 4.0 / 2019-04-21 / obs. 35628948

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 65 botanical countries

Regions where Juncus ranarius is native: Algeria, Morocco, Altay, Amur, Buryatiya, China North-Central, China South-Central, China Southeast, Chita, Inner Mongolia, Irkutsk, Kamchatka, Khabarovsk, Kirgizstan, Krasnoyarsk, Kuril Is., Magadan, Mongolia, North Caucasus, Primorye, Qinghai, Sakhalin, Tadzhikistan, Transcaucasus, Tuva, West Siberia, Xinjiang, Yakutiya, Albania, Austria, Baleares, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Corse, Czechia-Slovakia, Denmark, East European Russia, Finland, France, Germany, Great Britain, Greece, Hungary, Iceland, Ireland, Italy, Krym, Netherlands, North European Russia, Northwest European Russia, Norway, Poland, Portugal, Romania, Sardegna, Sicilia, South European Russia, Spain, Sweden, Switzerland, Ukraine, Greenland AlgeriaMoroccoAltayAmurBuryatiyaChina North-CentralChina South-CentralChina SoutheastChitaInner MongoliaIrkutskKamchatkaKhabarovskKirgizstanKrasnoyarskMagadanMongoliaNorth CaucasusPrimoryeQinghaiSakhalinTadzhikistanTranscaucasusTuvaWest SiberiaXinjiangYakutiyaAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCorseCzechia-SlovakiaDenmarkEast European RussiaFinlandFranceGermanyGreeceHungaryIcelandIrelandItalyKrymNetherlandsNorth European RussiaNorthwest European RussiaNorwayPolandPortugalRomaniaSiciliaSouth European RussiaSpainSwedenSwitzerlandUkraineGreenland BalearesSardegna
Native distribution of Juncus ranarius, 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
Albania ALB EUROPE
Austria AUT
Baleares BAL
Baltic States BLT
Belarus BLR
Belgium BGM
Bulgaria BUL
Central European Russia RUC
Corse COR
Czechia-Slovakia CZE
Denmark DEN
East European Russia RUE
Finland FIN
France FRA
Germany GER
Great Britain GRB
Greece GRC
Hungary HUN
Iceland ICE
Ireland IRE
Italy ITA
Krym KRY
Netherlands NET
North European Russia RUN
Northwest European Russia RUW
Norway NOR
Poland POL
Portugal POR
Romania ROM
Sardegna SAR
Sicilia SIC
South European Russia RUS
Spain SPA
Sweden SWE
Switzerland SWI
Ukraine UKR
Altay ALT ASIA-TEMPERATE
Amur AMU
Buryatiya BRY
China North-Central CHN
China South-Central CHC
China Southeast CHS
Chita CTA
Inner Mongolia CHI
Irkutsk IRK
Kamchatka KAM
Khabarovsk KHA
Kirgizstan KGZ
Krasnoyarsk KRA
Kuril Is. KUR
Magadan MAG
Mongolia MON
North Caucasus NCS
Primorye PRM
Qinghai CHQ
Sakhalin SAK
Tadzhikistan TZK
Transcaucasus TCS
Tuva TVA
West Siberia WSB
Xinjiang CHX
Yakutiya YAK
Algeria ALG AFRICA
Morocco MOR
Greenland GNL NORTHERN AMERICA

Not drawn on the map: Kuril Is., Great Britain. 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.

Where it actually grows measured, from 143 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -22.4 °C -4.0 °C 9.4 °C
Warmest month, mean daily high 17.5 °C 23.2 °C 30.5 °C
Annual rainfall 272 mm 613 mm 1,358 mm
Rainfall in the driest quarter 4 mm 97 mm 239 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 143 research-grade observations of Juncus ranarius 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 15 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.

  • Juncus ambiguus T.A.Cope & C.A.Stace
  • Juncus ambiguus var. ossoraicus (Novikov) Novikov
  • Juncus bufonius subsp. nastanthus (V.I.Krecz. & Gontsch.) Soó
  • Juncus bufonius subsp. ranarius (Songeon & E.P.Perrier) Hiitonen
  • Juncus bufonius unranked congestus Döll
  • Juncus bufonius var. fasciculatus W.D.J.Koch
  • Juncus bufonius var. halophilus Buchenau & Fernald
  • Juncus bufonius var. ranarius (Songeon & E.P.Perrier) Farw.
  • Juncus hybridus subsp. nastanthus (V.I.Krecz. & Gontsch.) Novikov
  • Juncus hybridus var. nastanthus Novikov
  • Juncus mutabilis var. ranarius (Songeon & E.P.Perrier) Nyman
  • Juncus nastanthus V.Krecz. & Bobr.
  • Juncus nastanthus V.I.Krecz. & Gontsch.
  • Juncus ranarius var. ossoraicus Novikov
  • Tenageia ranaria (Songeon & E.P.Perrier) Fourr.

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. USDA PLANTS Database. common name, checklist symbol JUAM3. public domain. 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.