Elymus smithii(Rydb.) Gould

western wheatgrass

WFO wfo-0000866722 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Elymus smithii, photographed by Cecelia Alexander
fig. a Cecelia Alexander, CC0 1.0 / 2022-05-27 / obs. 201106625
Elymus smithii, photographed by Reid Hardin
fig. b Reid Hardin, CC BY 4.0 / obs. 121709052
Elymus smithii, photographed by Laura Holloway
fig. c Laura Holloway, CC0 1.0 / obs. 116417687
Elymus smithii, photographed by Ryan Donnelly
fig. d Ryan Donnelly, CC BY 4.0 / obs. 77053925
Elymus smithii, photographed by Cleveland Powell
fig. e Cleveland Powell, CC BY 4.0 / obs. 69079780
Elymus smithii, photographed by Brian Dickerson
fig. f Brian Dickerson, CC0 1.0 / obs. 43805314
Elymus smithii, photographed by Cecelia Alexander
fig. g Cecelia Alexander, CC0 1.0 / obs. 18852712
Elymus smithii, photographed by Matt Lavin
fig. h Matt Lavin, CC BY 4.0 / obs. 152692779

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 39 botanical countries

Regions where Elymus smithii is native: Alaska, Alberta, Arizona, British Columbia, California, Colorado, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Manitoba, Massachusetts, Mexico Northeast, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Mexico, New York, North Dakota, Ohio, Oklahoma, Ontario, Oregon, Québec, Saskatchewan, South Dakota, Tennessee, Texas, Utah, Washington, Wisconsin, Wyoming AlaskaAlbertaArizonaBritish ColumbiaCaliforniaColoradoGeorgiaIdahoIllinoisIndianaIowaKansasKentuckyManitobaMassachusettsMexico NortheastMichiganMinnesotaMissouriMontanaNebraskaNevadaNew HampshireNew MexicoNew YorkNorth DakotaOhioOklahomaOntarioOregonQuébecSaskatchewanSouth DakotaTennesseeTexasUtahWashingtonWisconsinWyoming
Native distribution of Elymus smithii, 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
Alberta ABT
Arizona ARI
British Columbia BRC
California CAL
Colorado COL
Georgia GEO
Idaho IDA
Illinois ILL
Indiana INI
Iowa IOW
Kansas KAN
Kentucky KTY
Manitoba MAN
Massachusetts MAS
Mexico Northeast MXE
Michigan MIC
Minnesota MIN
Missouri MSO
Montana MNT
Nebraska NEB
Nevada NEV
New Hampshire NWH
New Mexico NWM
New York NWY
North Dakota NDA
Ohio OHI
Oklahoma OKL
Ontario ONT
Oregon ORE
Québec QUE
Saskatchewan SAS
South Dakota SDA
Tennessee TEN
Texas TEX
Utah UTA
Washington WAS
Wisconsin WIS
Wyoming WYO

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 391 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -19.0 °C -8.4 °C 0.3 °C
Warmest month, mean daily high 23.4 °C 29.1 °C 33.5 °C
Annual rainfall 311 mm 440 mm 953 mm
Rainfall in the driest quarter 27 mm 45 mm 101 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 391 research-grade observations of Elymus smithii 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 23 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.

  • Agropyron glaucum var. occidentale Scribn.
  • Agropyron molle (Scribn. & J.G.Sm.) Rydb.
  • Agropyron occidentale (Scribn.) Scribn.
  • Agropyron occidentale var. molle (Scribn. & J.G.Sm.) Scribn.
  • Agropyron occidentale var. occidentale
  • Agropyron occidentale var. palmeri (Scribn. & J.G.Sm.) Scribn.
  • Agropyron palmeri (Scribn. & J.G.Sm.) Rydb.
  • Agropyron smithii Rydb.
  • Agropyron smithii f. molle (Scribn. & J.G.Sm.) Gillett & Senn
  • Agropyron smithii var. molle (Scribn. & J.G.Sm.) M.E.Jones
  • Agropyron smithii var. palmeri (Scribn. & J.G.Sm.) A.Heller
  • Agropyron smithii var. smithii
  • Agropyron smithii var. typicum Waterf.
  • Agropyron spicatum var. molle Scribn. & J.G.Sm.
  • Agropyron spicatum var. palmeri Scribn. & J.G.Sm.
  • Agropyron spicatum var. viride Farw.
  • Elytrigia smithii (Rydb.) Nevski
  • Elytrigia smithii var. molle (Scribn. & J.G.Sm.) Beetle
  • Pascopyrum smithii (Rydb.) Á.Löve
  • Pascopyrum smithii (Rydb.) Barkworth & D.R.Dewey
  • Zeia mollis (Scribn. & J.G.Sm.) Lunell
  • Zeia occidentalis (Scribn.) Lunell
  • Zeia smithii (Rydb.) Lunell

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 PASM. public domain. 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.