Carex flaccaSchreb.

glaucous sedgeheath sedge

WFO wfo-0000346645 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Carex flacca, photographed by Yves Bas
fig. a Yves Bas, CC BY 4.0 / 2022-05-27 / obs. 201945524

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 53 botanical countries

Regions where Carex flacca is native: Algeria, Libya, Morocco, Tunisia, Cyprus, East Aegean Is., Iran, Iraq, Lebanon-Syria, North Caucasus, Palestine, Transcaucasus, Türkiye, Pakistan, Albania, Austria, Baleares, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Corse, Czechia-Slovakia, Denmark, East European Russia, Finland, Føroyar, France, Germany, Great Britain, Greece, Hungary, Iceland, Ireland, Italy, Kriti, Krym, Netherlands, Northwest European Russia, Norway, NW. Balkan Pen., Poland, Portugal, Romania, Sardegna, Sicilia, South European Russia, Spain, Sweden, Switzerland, Türkiye-in-Europe, Ukraine AlgeriaLibyaMoroccoTunisiaCyprusEast Aegean Is.IranIraqLebanon-SyriaNorth CaucasusPalestineTranscaucasusTürkiyePakistanAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCorseCzechia-SlovakiaDenmarkEast European RussiaFinlandFranceGermanyGreeceHungaryIcelandIrelandItalyKritiKrymNetherlandsNorthwest European RussiaNorwayNW. Balkan Pen.PolandPortugalRomaniaSiciliaSouth European RussiaSpainSwedenSwitzerlandTürkiye-in-EuropeUkraine BalearesFøroyarSardegna
Native distribution of Carex flacca, 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
Føroyar FOR
France FRA
Germany GER
Great Britain GRB
Greece GRC
Hungary HUN
Iceland ICE
Ireland IRE
Italy ITA
Kriti KRI
Krym KRY
Netherlands NET
Northwest European Russia RUW
Norway NOR
NW. Balkan Pen. YUG
Poland POL
Portugal POR
Romania ROM
Sardegna SAR
Sicilia SIC
South European Russia RUS
Spain SPA
Sweden SWE
Switzerland SWI
Türkiye-in-Europe TUE
Ukraine UKR
Cyprus CYP ASIA-TEMPERATE
East Aegean Is. EAI
Iran IRN
Iraq IRQ
Lebanon-Syria LBS
North Caucasus NCS
Palestine PAL
Transcaucasus TCS
Türkiye TUR
Algeria ALG AFRICA
Libya LBY
Morocco MOR
Tunisia TUN
Pakistan PAK ASIA-TROPICAL

Not drawn on the map: Great Britain. 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.

Flowering 262 in flower of 376 examined

Proportion of examined Carex flacca in flower, by month
Month In flower Examined Share 95% interval
Jan 0 2 too few examined
Feb 0 8 0% 0% to 32%
Mar 43 50 86% 74% to 93%
Apr 145 159 91% 86% to 95%
May 53 75 71% 60% to 80%
Jun 13 40 33% 20% to 48%
Jul 3 22 14% 5% to 33%
Aug 0 7 0% 0% to 35%
Sep 0 4 too few examined
Oct 1 4 too few examined
Nov 4 5 80% 38% to 96%
Dec 0 0 too few examined

Peak flowering in Apr. Each bar is the share of Carex flacca 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. 262 of 376 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 4 months have fewer than 5 examined observations, so no proportion is drawn for them. 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.

Where it actually grows measured, from 2,013 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -10.0 °C -2.6 °C 4.9 °C
Warmest month, mean daily high 17.5 °C 23.0 °C 28.8 °C
Annual rainfall 584 mm 910 mm 1,745 mm
Rainfall in the driest quarter 72 mm 161 mm 309 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 2,013 research-grade observations of Carex flacca 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. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 144 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.

  • Carex acuminata Willd.
  • Carex ambleocarpa Willd.
  • Carex aspera Willd.
  • Carex bulbosa Drejer
  • Carex clavaeformis Hoppe
  • Carex cuspidata Host
  • Carex dinarica (Heuff.) Simonk.
  • Carex diversicolor Crantz
  • Carex diversicolor var. cuspidata (Host) Fiori
  • Carex erythrostachys Hoppe
  • Carex flacca f. castriferrei Soó
  • Carex flacca f. chlorocarpa R.Keller
  • Carex flacca f. melanostachya R.Uechtr.
  • Carex flacca f. pallida Beck
  • Carex flacca f. tenuicula (Martrin-Donos) Soó
  • Carex flacca subsp. claviformis (Hoppe) Schinz & Thell.
  • Carex flacca subsp. claviformis (Hoppe) Malag.
  • Carex flacca subsp. cuspidata (Host) Vicioso
  • Carex flacca subsp. cuspidata (Host) Schinz & R.Keller
  • Carex flacca subsp. praetutiana (Parl.) Holub
  • Carex flacca subsp. serrulata (Biv.) Greuter
  • Carex flacca subsp. serrulata (Biv.) Malag.
  • Carex flacca subvar. cuspidata (Host) Maire & Weiller
  • Carex flacca var. acuminata (Trab.) C.Vicioso

and 120 more.

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.