Aira caryophylleaL.

Silvery Hair Grasssilver hairgrass

WFO wfo-0000844921 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 8 separate observations

Aira caryophyllea, photographed by Bonnie Semmling
fig. a Bonnie Semmling, CC BY 4.0 / 2022-05-15 / obs. 198000720
Aira caryophyllea, photographed by Trevor Van Loon
fig. b Trevor Van Loon, CC BY 4.0 / obs. 198537045
Aira caryophyllea, photographed by Yves Bas
fig. c Yves Bas, CC BY 4.0 / obs. 189181094
Aira caryophyllea, photographed by Dylan Wishart
fig. d Dylan Wishart, CC BY 4.0 / obs. 187227086
Aira caryophyllea, photographed by Leon Perrie
fig. e Leon Perrie, CC BY 4.0 / obs. 171269628
Aira caryophyllea, photographed by Kym Nicolson
fig. f Kym Nicolson, CC BY 4.0 / obs. 168193518
Aira caryophyllea, photographed by Pieter Pelser
fig. g Pieter Pelser, CC BY 4.0 / obs. 167532697
Aira caryophyllea, photographed by Leon Perrie
fig. h Leon Perrie, CC BY 4.0 / obs. 166370645

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 54 botanical countries

Regions where Aira caryophyllea is native: Algeria, Azores, Cameroon, Canary Is., Cape Verde, DR Congo, Ethiopia, Gulf of Guinea Is., Kenya, Madagascar, Madeira, Malawi, Morocco, Nigeria, Rwanda, Sudan-South Sudan, Tanzania, Tunisia, Uganda, East Aegean Is., Tibet, Transcaucasus, Türkiye, West Himalaya, Albania, Austria, Baleares, Baltic States, Belarus, Belgium, Bulgaria, Corse, Czechia-Slovakia, Denmark, France, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Krym, Netherlands, NW. Balkan Pen., Poland, Portugal, Romania, Sardegna, Sicilia, Spain, Sweden, Switzerland, Türkiye-in-Europe, Ukraine AlgeriaCameroonDR CongoEthiopiaGulf of Guinea Is.KenyaMadagascarMalawiMoroccoNigeriaRwandaSudan-South SudanTanzaniaTunisiaUgandaEast Aegean Is.TibetTranscaucasusTürkiyeWest HimalayaAlbaniaAustriaBaltic StatesBelarusBelgiumBulgariaCorseCzechia-SlovakiaDenmarkFranceGermanyGreeceHungaryIrelandItalyKrymNetherlandsNW. Balkan Pen.PolandPortugalRomaniaSiciliaSpainSwedenSwitzerlandTürkiye-in-EuropeUkraine AzoresCanary Is.Cape VerdeMadeiraBalearesSardegna
Native distribution of Aira caryophyllea, 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
Corse COR
Czechia-Slovakia CZE
Denmark DEN
France FRA
Germany GER
Great Britain GRB
Greece GRC
Hungary HUN
Ireland IRE
Italy ITA
Krym KRY
Netherlands NET
NW. Balkan Pen. YUG
Poland POL
Portugal POR
Romania ROM
Sardegna SAR
Sicilia SIC
Spain SPA
Sweden SWE
Switzerland SWI
Türkiye-in-Europe TUE
Ukraine UKR
Algeria ALG AFRICA
Azores AZO
Cameroon CMN
Canary Is. CNY
Cape Verde CVI
DR Congo ZAI
Ethiopia ETH
Gulf of Guinea Is. GGI
Kenya KEN
Madagascar MDG
Madeira MDR
Malawi MLW
Morocco MOR
Nigeria NGA
Rwanda RWA
Sudan-South Sudan SUD
Tanzania TAN
Tunisia TUN
Uganda UGA
East Aegean Is. EAI ASIA-TEMPERATE
Tibet CHT
Transcaucasus TCS
Türkiye TUR
West Himalaya WHM 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 45 in flower of 115 examined

Peak flowering in Nov. Each bar is the share of Aira caryophyllea 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. 45 of 115 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 1,657 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -2.6 °C 3.5 °C 9.4 °C
Warmest month, mean daily high 17.5 °C 23.4 °C 34.4 °C
Annual rainfall 515 mm 948 mm 1,982 mm
Rainfall in the driest quarter 6 mm 136 mm 289 mm

It is found where winters bring light 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 1,657 research-grade observations of Aira caryophyllea 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 90 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.

  • Agrostis caryophyllea (L.) Salisb.
  • Aira aggregata Timeroy ex Bor.
  • Aira aggregata var. sabulosa Mabille
  • Aira armoricana F.Albers
  • Aira bachiti Hochst. ex Chiov.
  • Aira bachitii Hochst. ex C.E.Hubb.
  • Aira baetica Trin.
  • Aira canescens Host
  • Aira caryophyllea f. pallescens Neuman
  • Aira caryophyllea subsp. anceps (Ces., Pass. & Gibelli) Arcang.
  • Aira caryophyllea subsp. armoricana (F.Albers) Kerguélen
  • Aira caryophyllea subsp. caryophyllea
  • Aira caryophyllea subsp. multiculmis (Dumort.) Bonnier & Layens
  • Aira caryophyllea subsp. multiculmis (Dumort.) Bonnier & Layens
  • Aira caryophyllea subsp. plesiantha (Jord. ex Boreau) K.Richt.
  • Aira caryophyllea subsp. reverchonii (Murb.) Maire
  • Aira caryophyllea var. aggregata (Timeroy ex Bor.) Syme
  • Aira caryophyllea var. aggregata (Timeroy ex Bor) Asch. & Graebn.
  • Aira caryophyllea var. biaristata (Emb. & Maire) Maire
  • Aira caryophyllea var. caryophyllea
  • Aira caryophyllea var. curta (Jord.) Rouy ex Douin
  • Aira caryophyllea var. divergens N.H.F.Desp.
  • Aira caryophyllea var. expansa K.Koch
  • Aira caryophyllea var. hostii (Steud.) Rouy

and 66 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.