Oryzopsis asperifoliaMichx.

roughleaf ricegrass

WFO wfo-0000882482 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Oryzopsis asperifolia, photographed by Mary Krieger
fig. a Mary Krieger, CC BY 4.0 / 2022-05-27 / obs. 201216262
Oryzopsis asperifolia, photographed by Henry "Nick" Robertson
fig. b Henry "Nick" Robertson, CC BY-SA 4.0 / obs. 198995400
Oryzopsis asperifolia, photographed by Henry "Nick" Robertson
fig. c Henry "Nick" Robertson, CC BY-SA 4.0 / obs. 197393881
Oryzopsis asperifolia, photographed by Étienne Lacroix-Carignan
fig. d Étienne Lacroix-Carignan, CC0 1.0 / obs. 197000536
Oryzopsis asperifolia, photographed by Henry "Nick" Robertson
fig. e Henry "Nick" Robertson, CC BY-SA 4.0 / obs. 193381410
Oryzopsis asperifolia, photographed by Brandon Corder
fig. f Brandon Corder, CC BY 4.0 / obs. 157161700
Oryzopsis asperifolia, photographed by Henry "Nick" Robertson
fig. g Henry "Nick" Robertson, CC BY-SA 4.0 / obs. 155051211
Oryzopsis asperifolia, photographed by Reuven Martin
fig. h Reuven Martin, CC0 1.0 / obs. 138255790

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 40 botanical countries

Regions where Oryzopsis asperifolia is native: Alberta, British Columbia, Colorado, Connecticut, Idaho, Illinois, Indiana, Iowa, Maine, Manitoba, Maryland, Massachusetts, Michigan, Minnesota, Montana, New Brunswick, New Hampshire, New Jersey, New Mexico, New York, Newfoundland, North Dakota, Northwest Territories, Nova Scotia, Ohio, Ontario, Pennsylvania, Prince Edward I., Québec, Rhode I., Saskatchewan, South Dakota, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming, Yukon AlbertaBritish ColumbiaColoradoConnecticutIdahoIllinoisIndianaIowaMaineManitobaMarylandMassachusettsMichiganMinnesotaMontanaNew BrunswickNew HampshireNew JerseyNew MexicoNew YorkNewfoundlandNorth DakotaNorthwest TerritoriesNova ScotiaOhioOntarioPennsylvaniaPrince Edward I.QuébecSaskatchewanSouth DakotaUtahVermontVirginiaWashingtonWest VirginiaWisconsinWyomingYukon Rhode I.
Native distribution of Oryzopsis asperifolia, 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
Alberta ABT NORTHERN AMERICA
British Columbia BRC
Colorado COL
Connecticut CNT
Idaho IDA
Illinois ILL
Indiana INI
Iowa IOW
Maine MAI
Manitoba MAN
Maryland MRY
Massachusetts MAS
Michigan MIC
Minnesota MIN
Montana MNT
New Brunswick NBR
New Hampshire NWH
New Jersey NWJ
New Mexico NWM
New York NWY
Newfoundland NFL
North Dakota NDA
Northwest Territories NWT
Nova Scotia NSC
Ohio OHI
Ontario ONT
Pennsylvania PEN
Prince Edward I. PEI
Québec QUE
Rhode I. RHO
Saskatchewan SAS
South Dakota SDA
Utah UTA
Vermont VER
Virginia VRG
Washington WAS
West Virginia WVA
Wisconsin WIS
Wyoming WYO
Yukon YUK

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 135 in flower of 207 examined

Peak flowering in May. Each bar is the share of Oryzopsis asperifolia 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. 135 of 207 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 8 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.

Also published as 7 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.

  • Dilepyrum angustifolium Raf.
  • Oryzopsis aspera Muhl.
  • Oryzopsis leucosperma Walp.
  • Oryzopsis mutica Link
  • Urachne asperifolia (Michx.) Trin.
  • Urachne leucosperma Link
  • Urachne mutica (Link) Steud.

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.