Piptochaetium avenaceum(L.) Parodi

blackseed speargrass

WFO wfo-0000890794 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Piptochaetium avenaceum, photographed by Michael J. Papay
fig. a Michael J. Papay, CC BY 4.0 / 2022-04-24 / obs. 190605217
Piptochaetium avenaceum, photographed by Leila Dasher
fig. b Leila Dasher, CC BY 4.0 / obs. 189154515
Piptochaetium avenaceum, photographed by Michael J. Papay
fig. c Michael J. Papay, CC BY 4.0 / obs. 126428813
Piptochaetium avenaceum, photographed by Alan Weakley
fig. d Alan Weakley, CC0 1.0 / obs. 124882570
Piptochaetium avenaceum, photographed by Alan Weakley
fig. e Alan Weakley, CC0 1.0 / obs. 73473070
Piptochaetium avenaceum, photographed by Alan Weakley
fig. f Alan Weakley, CC0 1.0 / obs. 73204877
Piptochaetium avenaceum, photographed by Alan Weakley
fig. g Alan Weakley, CC0 1.0 / obs. 65848695
Piptochaetium avenaceum, photographed by runcator
fig. h runcator, CC BY 4.0 / obs. 56127193

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 30 botanical countries

Regions where Piptochaetium avenaceum is native: Alabama, Arkansas, Connecticut, Delaware, District of Columbia, Florida, Georgia, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Mexico Central, Mexico Northeast, Michigan, Mississippi, Missouri, New Jersey, New York, North Carolina, Ohio, Oklahoma, Ontario, Pennsylvania, Rhode I., South Carolina, Tennessee, Texas, Virginia, West Virginia AlabamaArkansasConnecticutFloridaGeorgiaIndianaKentuckyLouisianaMarylandMassachusettsMexico CentralMexico NortheastMichiganMississippiMissouriNew JerseyNew YorkNorth CarolinaOhioOklahomaOntarioPennsylvaniaSouth CarolinaTennesseeTexasVirginiaWest Virginia DelawareDistrict of ColumbiaRhode I.
Native distribution of Piptochaetium avenaceum, 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
Alabama ALA NORTHERN AMERICA
Arkansas ARK
Connecticut CNT
Delaware DEL
District of Columbia WDC
Florida FLA
Georgia GEO
Indiana INI
Kentucky KTY
Louisiana LOU
Maryland MRY
Massachusetts MAS
Mexico Central MXC
Mexico Northeast MXE
Michigan MIC
Mississippi MSI
Missouri MSO
New Jersey NWJ
New York NWY
North Carolina NCA
Ohio OHI
Oklahoma OKL
Ontario ONT
Pennsylvania PEN
Rhode I. RHO
South Carolina SCA
Tennessee TEN
Texas TEX
Virginia VRG
West Virginia WVA

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 665 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -3.5 °C 1.0 °C 8.0 °C
Warmest month, mean daily high 26.5 °C 31.3 °C 33.8 °C
Annual rainfall 1,093 mm 1,272 mm 1,574 mm
Rainfall in the driest quarter 205 mm 265 mm 322 mm

It is found where winters bring light 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 665 research-grade observations of Piptochaetium avenaceum 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 11 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.

  • Piptochaetium avenacellum Barkworth
  • Piptochaetium leianthum (Hitchc.) Beetle
  • Podopogon avenaceus (L.) Raf.
  • Podopogon barbatus (Pers.) Raf.
  • Stipa avenacea L.
  • Stipa avenacea var. avenacea
  • Stipa avenacea var. bicolor Eaton & Wright
  • Stipa barbata Michx.
  • Stipa diffusa Willd. ex Steud.
  • Stipa leiantha Hitchc.
  • Stipa virginica Pers.

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.