Leymus racemosus(Lam.) Tzvelev

mammoth wildrye

WFO wfo-0000878229 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 8 separate observations

Leymus racemosus, photographed by Galyna Mykytynets
fig. a Galyna Mykytynets, CC BY 4.0 / 2021-09-08 / obs. 172581976
Leymus racemosus, photographed by Galyna Mykytynets
fig. b Galyna Mykytynets, CC BY 4.0 / obs. 173522250
Leymus racemosus, photographed by Galyna Mykytynets
fig. c Galyna Mykytynets, CC BY 4.0 / obs. 172998890
Leymus racemosus, photographed by Galyna Mykytynets
fig. d Galyna Mykytynets, CC BY 4.0 / obs. 173745115
Leymus racemosus, photographed by Matt Lavin
fig. e Matt Lavin, CC BY 4.0 / obs. 107732379
Leymus racemosus, photographed by Sue Carnahan
fig. f Sue Carnahan, CC BY 4.0 / obs. 61155782
Leymus racemosus, photographed by Joe Potter Butler
fig. g Joe Potter Butler, CC BY 4.0 / obs. 52299693
Leymus racemosus, photographed by Galyna Mykytynets
fig. h Galyna Mykytynets, CC BY 4.0 / obs. 178118916

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 25 botanical countries

Regions where Leymus racemosus is native: Altay, Buryatiya, Kazakhstan, Kirgizstan, Krasnoyarsk, Mongolia, North Caucasus, Transcaucasus, Türkiye, Turkmenistan, Tuva, Uzbekistan, West Siberia, Xinjiang, Belarus, Bulgaria, Central European Russia, East European Russia, Greece, Krym, Northwest European Russia, Romania, South European Russia, Türkiye-in-Europe, Ukraine AltayBuryatiyaKazakhstanKirgizstanKrasnoyarskMongoliaNorth CaucasusTranscaucasusTürkiyeTurkmenistanTuvaUzbekistanWest SiberiaXinjiangBelarusBulgariaCentral European RussiaEast European RussiaGreeceKrymNorthwest European RussiaRomaniaSouth European RussiaTürkiye-in-EuropeUkraine
Native distribution of Leymus racemosus, 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
Altay ALT ASIA-TEMPERATE
Buryatiya BRY
Kazakhstan KAZ
Kirgizstan KGZ
Krasnoyarsk KRA
Mongolia MON
North Caucasus NCS
Transcaucasus TCS
Türkiye TUR
Turkmenistan TKM
Tuva TVA
Uzbekistan UZB
West Siberia WSB
Xinjiang CHX
Belarus BLR EUROPE
Bulgaria BUL
Central European Russia RUC
East European Russia RUE
Greece GRC
Krym KRY
Northwest European Russia RUW
Romania ROM
South European Russia RUS
Türkiye-in-Europe TUE
Ukraine UKR

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 586 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -18.5 °C -6.3 °C 4.5 °C
Warmest month, mean daily high 19.9 °C 27.2 °C 32.0 °C
Annual rainfall 249 mm 454 mm 700 mm
Rainfall in the driest quarter 43 mm 87 mm 143 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 586 research-grade observations of Leymus racemosus 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 33 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.

  • Elymus arenarius S.G.Gmel.
  • Elymus arenarius subsp. sabulosus (M.Bieb.) Beldie
  • Elymus arenarius var. giganteus (Vahl) Schmalh.
  • Elymus arenarius var. sabulosus (M.Bieb.) Trevir.
  • Elymus attenuatus (Griseb.) K.Richt.
  • Elymus giganteus Vahl
  • Elymus giganteus f. attenuatus Griseb.
  • Elymus giganteus f. crassinervius Karav. & Kir.
  • Elymus giganteus f. pruinosus Roshev.
  • Elymus giganteus var. alterniflorus Regel
  • Elymus giganteus var. attenuatus Griseb.
  • Elymus giganteus var. crassinervius Kar. & Kir.
  • Elymus giganteus var. cylindraceus Roshev.
  • Elymus giganteus var. sabulosus (M.Bieb.) Hack.
  • Elymus macrostachys Spreng.
  • Elymus mexicanus Cav.
  • Elymus racemosus Lam.
  • Elymus racemosus var. sabulosus (M.Bieb.) Bowden
  • Elymus sabulosus M.Bieb.
  • Elymus sabulosus var. depauperatus Bornm.
  • Hordeum giganteum (Vahl) Raspail
  • Leymus crassinervius (Kar. & Kir.) Baikov & Lipin
  • Leymus giganteus (Vahl) Pilg.
  • Leymus klokovii (Tzvelev) Baikov & Lipin

and 9 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.