Patis racemosa(Sm.) Romasch., P.M.Peterson & Soreng

blackseed ricegrass

WFO wfo-0001043144 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Patis racemosa, photographed by Henry "Nick" Robertson
fig. a Henry "Nick" Robertson, CC BY-SA 4.0 / 2021-11-28 / obs. 170669100
Patis racemosa, photographed by Henry "Nick" Robertson
fig. b Henry "Nick" Robertson, CC BY-SA 4.0 / obs. 138635947
Patis racemosa, photographed by Reuven Martin
fig. c Reuven Martin, CC0 1.0 / obs. 99713530
Patis racemosa, photographed by Owen Strickland
fig. d Owen Strickland, CC BY 4.0 / obs. 90726345
Patis racemosa, photographed by Reuven Martin
fig. e Reuven Martin, CC0 1.0 / obs. 88975892
Patis racemosa, photographed by Quinten Wiegersma
fig. f Quinten Wiegersma, CC BY 4.0 / obs. 58074282
Patis racemosa, photographed by Reuven Martin
fig. g Reuven Martin, CC0 1.0 / obs. 48627171
Patis racemosa, photographed by Reuven Martin
fig. h Reuven Martin, CC0 1.0 / obs. 45687026

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 28 botanical countries

Regions where Patis racemosa is native: Connecticut, Delaware, Illinois, Indiana, Iowa, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Dakota, Ohio, Ontario, Pennsylvania, Québec, Rhode I., South Dakota, Tennessee, Vermont, Virginia, West Virginia, Wisconsin ConnecticutIllinoisIndianaIowaKentuckyMaineMarylandMassachusettsMichiganMinnesotaMissouriNebraskaNew HampshireNew JerseyNew YorkNorth DakotaOhioOntarioPennsylvaniaQuébecSouth DakotaTennesseeVermontVirginiaWest VirginiaWisconsin DelawareRhode I.
Native distribution of Patis racemosa, 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
Connecticut CNT NORTHERN AMERICA
Delaware DEL
Illinois ILL
Indiana INI
Iowa IOW
Kentucky KTY
Maine MAI
Maryland MRY
Massachusetts MAS
Michigan MIC
Minnesota MIN
Missouri MSO
Nebraska NEB
New Hampshire NWH
New Jersey NWJ
New York NWY
North Dakota NDA
Ohio OHI
Ontario ONT
Pennsylvania PEN
Québec QUE
Rhode I. RHO
South Dakota SDA
Tennessee TEN
Vermont VER
Virginia VRG
West Virginia WVA
Wisconsin WIS

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 456 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -14.7 °C -11.3 °C -6.3 °C
Warmest month, mean daily high 23.4 °C 25.7 °C 28.1 °C
Annual rainfall 827 mm 981 mm 1,306 mm
Rainfall in the driest quarter 80 mm 197 mm 278 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 456 research-grade observations of Patis racemosa 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 6 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.

  • Milium racemosum Sm.
  • Oryzopsis melanocarpa Muhl.
  • Piptatherum nigrum Torr.
  • Piptatherum racemosum (Sm.) Eaton
  • Urachne melanosperma Link
  • Urachne racemosa (Sm.) Trin.

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 PARA2. 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.