Leymus mollis (American Dunegrass)

Plate 1 figs. a–h · 8 separate observations

Leymus mollis, photographed by Braden J. Judson — fig. a Braden J. Judson, CC0 1.0 / 2022-04-14 / obs. 188374083

Leymus mollis, photographed by Garth Harwood — fig. b Garth Harwood, CC BY 4.0 / obs. 177630458

Leymus mollis, photographed by Aiva Noringseth — fig. c Aiva Noringseth, CC BY 4.0 / obs. 175938225

Leymus mollis, photographed by Andrew Meeds — fig. e Andrew Meeds, CC BY 4.0 / obs. 174907655

Leymus mollis, photographed by Matt Muir — fig. f Matt Muir, CC BY 4.0 / obs. 150789975

Leymus mollis, photographed by Chase Mathey — fig. g Chase Mathey, CC BY 4.0 / obs. 144255670

Leymus mollis, photographed by Jason Grant — fig. h Jason Grant, CC BY 4.0 / obs. 144044961

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: The New York Botanical Garden
Accession: 3697358
Filed as: Leymus mollis subsp. villosissimus (Scribn.) Á.Löve & D.Löve
Det. by: J. M. Saarela 2015-01-01
Collected: J. M. Saarela 2014-07-18
Origin: CA
The sheet: View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. 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 herbarium sheets never recorded a determiner, which is ordinary.

Native range 38 botanical countries

Native distribution of Leymus mollis, 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.

Region	TDWG code	Continent
Alaska	ASK	NORTHERN AMERICA
Alberta	ABT
Aleutian Is.	ALU
British Columbia	BRC
California	CAL
Greenland	GNL
Illinois	ILL
Labrador	LAB
Maine	MAI
Manitoba	MAN
Massachusetts	MAS
Michigan	MIC
New Brunswick	NBR
New Hampshire	NWH
Newfoundland	NFL
Northwest Territories	NWT
Nova Scotia	NSC
Nunavut	NUN
Ontario	ONT
Oregon	ORE
Pennsylvania	PEN
Prince Edward I.	PEI
Québec	QUE
Saskatchewan	SAS
Washington	WAS
Wisconsin	WIS
Yukon	YUK
China North-Central	CHN	ASIA-TEMPERATE
Japan	JAP
Kamchatka	KAM
Khabarovsk	KHA
Korea	KOR
Kuril Is.	KUR
Magadan	MAG
Manchuria	CHM
Mongolia	MON
Primorye	PRM
Sakhalin	SAK

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.

Flowering 37 in flower of 209 examined

29%

60%

35%

30%

11%

Proportion of examined Leymus mollis in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	3	too few examined
Feb	0	10	0%	0% to 28%
Mar	0	8	0%	0% to 32%
Apr	2	7	29%	8% to 64%
May	9	15	60%	36% to 80%
Jun	9	26	35%	19% to 54%
Jul	11	37	30%	17% to 46%
Aug	4	54	7%	3% to 18%
Sep	2	19	11%	3% to 31%
Oct	0	14	0%	0% to 22%
Nov	0	9	0%	0% to 30%
Dec	0	7	0%	0% to 35%

Peak flowering in May. Each bar is the share of Leymus mollis 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. 37 of 209 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. One month has fewer than 5 examined observations, so no proportion is drawn for it. 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 2,019 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-19.7 °C	2.2 °C	7.6 °C
Warmest month, mean daily high	13.4 °C	18.1 °C	23.4 °C
Annual rainfall	597 mm	1,239 mm	3,512 mm
Rainfall in the driest quarter	22 mm	150 mm	420 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 2,019 research-grade observations of Leymus mollis 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 30 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.

Elyleymus aleuticus (Hultén) B.R.Baum
Elyleymus uclueletensis (Bowden) B.R.Baum
Elymus aleuticus Hultén
Elymus ampliculmis Prov.
Elymus arenarius f. compositus Abrom.
Elymus arenarius subsp. mollis (Trin.) Hultén
Elymus arenarius var. brevispicus (Scribn. & J.G.Sm.) B.Boivin
Elymus arenarius var. compositus (Abrom.) H.St.John
Elymus arenarius var. coreensis Hack.
Elymus arenarius var. mollis (Trin.) Koidz.
Elymus arenarius var. scabrinervis (Bowden) B.Boivin
Elymus arenarius var. simulans (Bowden) B.Boivin
Elymus arenarius var. villosus E.Mey.
Elymus capitatus Scribn.
Elymus cladostachys Turcz.
Elymus dives J.Presl
Elymus mollis Trin.
Elymus mollis f. mollis
Elymus mollis f. moniliformis Lepage
Elymus mollis f. scabrinervis Bowden
Elymus mollis f. simulans Bowden
Elymus mollis var. brevispicus Scribn. & J.G.Sm.
Elymus mollis var. coreensis (Hack.) Honda
Elymus mollis var. japonicus Bowden

and 6 more.

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
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.