Carex macrochaetaC.A.Mey.

Alaska large awn sedgeLongawn sedgelarge-awned sedgelongawn sedge

WFO wfo-0000348601 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 8 separate observations

Carex macrochaeta, photographed by Trevor Van Loon
fig. a Trevor Van Loon, CC BY 4.0 / 2021-08-14 / obs. 152970423

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
Smithsonian, US National Herbarium
Accession
US 3501633
Filed as
Carex macrochaeta C.A.Mey.
Det. by
Shetler, Stanwyn G., (US), NMNH
Collected
W. Sladen 1960-07-11
Origin
US
The sheet
View the digitised specimen (CC0 1.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. We link to the digitised sheet rather than rehosting it, because the holding institutions do not serve their images to third parties reliably and we are not going to show you a picture we cannot actually deliver. 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 sheets never recorded a determiner, which is ordinary.

Native range 10 botanical countries

Regions where Carex macrochaeta is native: Altay, Kamchatka, Kuril Is., Magadan, Alaska, Aleutian Is., British Columbia, Oregon, Washington, Yukon AltayKamchatkaMagadanAlaskaBritish ColumbiaOregonWashingtonYukon
Native distribution of Carex macrochaeta, 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.
RegionTDWG codeContinent
Alaska ASK NORTHERN AMERICA
Aleutian Is. ALU
British Columbia BRC
Oregon ORE
Washington WAS
Yukon YUK
Altay ALT ASIA-TEMPERATE
Kamchatka KAM
Kuril Is. KUR
Magadan MAG

Not drawn on the map: Kuril Is., 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 187 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -16.1 °C -5.0 °C 1.1 °C
Warmest month, mean daily high 11.3 °C 14.3 °C 19.9 °C
Annual rainfall 1,050 mm 3,220 mm 5,359 mm
Rainfall in the driest quarter 121 mm 422 mm 728 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 187 research-grade observations of Carex macrochaeta 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 5 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 kuehleweinii Gand.
  • Carex macrochaeta var. emarginata Holm
  • Carex macrochaeta var. macrochlaena Holm
  • Carex macrochaeta var. platycarpa Kük.
  • Carex macrochaeta var. subrigida Kük. ex J.M.Macoun

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.