Koeleria vallesiana(Honck.) Gaudin

Somerset hair grass

WFO wfo-0001096105 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 4 observations

This species has been photographed under an open licence only 4 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.

Koeleria vallesiana, photographed by Denys Vynokurov
fig. a Denys Vynokurov, CC BY 4.0 / 2021-04-13 / obs. 120683660

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.

Where it actually grows measured, from 124 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -7.9 °C -0.2 °C 3.0 °C
Warmest month, mean daily high 17.3 °C 25.3 °C 31.6 °C
Annual rainfall 403 mm 909 mm 2,100 mm
Rainfall in the driest quarter 61 mm 142 mm 298 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 124 research-grade observations of Koeleria vallesiana 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 Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.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 60 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.

  • Aira valesiaca Colla
  • Aira valesiana All.
  • Aira vallesiana (Honck.) All.
  • Airochloa pubescens Link
  • Airochloa vallesiana (Honck.) Link
  • Brachystylus setaceus (Pers.) Dulac
  • Festuca splendens Pourr.
  • Koeleria alpicola Godr. & Gren.
  • Koeleria andreanszkyi Ujhelyi
  • Koeleria aurata Bubani
  • Koeleria castellana Boiss. & Reut.
  • Koeleria castellana var. velutina Willk.
  • Koeleria cristata var. pectinata (Lam.) Pers.
  • Koeleria epauneroi Kerguélen
  • Koeleria gandreanszkyi Kerguélen
  • Koeleria intricata Genty
  • Koeleria langeana Willk. & Lange
  • Koeleria linkii Kunth
  • Koeleria narbonnensis Domin
  • Koeleria nitida Ten.
  • Koeleria pauneroi Ujhelyi
  • Koeleria pectinata (Lam.) Shinners
  • Koeleria scheuchzeri Rouy
  • Koeleria setacea (Pers.) DC.

and 36 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. USDA PLANTS Database. common name, checklist symbol KOVA2. public domain. Retrieved 2026-07-13.

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. It has no native range either: Kew's checklist does not cover this taxon.