Plate 1 figs. a–h · 7 observations
This species has been photographed under an open licence only 7 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.
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
- The New York Botanical Garden
- Accession
- 2381072
- Filed as
- Juncus castaneus Sm.
- Det. by
- not recorded on this sheet
- Collected
- G. R. Brassard
- Origin
- CA
- 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 52 botanical countries
| Region | TDWG code | Continent |
|---|---|---|
| Altay | ALT | ASIA-TEMPERATE |
| Buryatiya | BRY | |
| China North-Central | CHN | |
| China South-Central | CHC | |
| Chita | CTA | |
| Inner Mongolia | CHI | |
| Irkutsk | IRK | |
| Japan | JAP | |
| Kamchatka | KAM | |
| Khabarovsk | KHA | |
| Kirgizstan | KGZ | |
| Korea | KOR | |
| Krasnoyarsk | KRA | |
| Kuril Is. | KUR | |
| Magadan | MAG | |
| Manchuria | CHM | |
| Mongolia | MON | |
| Tuva | TVA | |
| West Siberia | WSB | |
| Xinjiang | CHX | |
| Yakutiya | YAK | |
| Alaska | ASK | NORTHERN AMERICA |
| Alberta | ABT | |
| Aleutian Is. | ALU | |
| British Columbia | BRC | |
| Colorado | COL | |
| Greenland | GNL | |
| Labrador | LAB | |
| Manitoba | MAN | |
| Montana | MNT | |
| New Mexico | NWM | |
| Northwest Territories | NWT | |
| Nunavut | NUN | |
| Ontario | ONT | |
| Québec | QUE | |
| Saskatchewan | SAS | |
| Utah | UTA | |
| Wyoming | WYO | |
| Yukon | YUK | |
| Austria | AUT | EUROPE |
| Czechia-Slovakia | CZE | |
| East European Russia | RUE | |
| Great Britain | GRB | |
| Iceland | ICE | |
| Italy | ITA | |
| North European Russia | RUN | |
| Norway | NOR | |
| Romania | ROM | |
| Svalbard | SVA | |
| Sweden | SWE | |
| Switzerland | SWI | |
| Ukraine | UKR |
Not drawn on the map: Kuril Is., Great Britain, Aleutian Is.. 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 202 observations
| Condition | 5th percentile | Median | 95th percentile |
|---|---|---|---|
| Coldest month, mean daily low | -33.4 °C | -24.5 °C | -10.5 °C |
| Warmest month, mean daily high | 8.9 °C | 15.3 °C | 20.6 °C |
| Annual rainfall | 281 mm | 592 mm | 1,839 mm |
| Rainfall in the driest quarter | 15 mm | 71 mm | 288 mm |
It is found where winters are arctic. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 202 research-grade observations of Juncus castaneus 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 14 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 castaneus f. pallidus (Buchenau) B.Boivin
- Juncus castaneus var. castaneus
- Juncus castaneus var. czetzii (Schur) Nyman
- Juncus castaneus var. fuscus Nakai
- Juncus castaneus var. koreanus Ohwi
- Juncus castaneus var. pallidus B.Boivin
- Juncus castaneus var. pallidus Buchenau
- Juncus czetzii Schur
- Juncus leucochlamys V.J.Zinger ex V.I.Krecz.
- Juncus leucochlamys subsp. borealis (Tolm.) Novikov
- Juncus leucochlamys var. borealis Tolm.
- Juncus satakei Kitag.
- Juncus triceps Rostk.
- Juncus triceps var. koreanus (Ohwi) Satake
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.