Aristida adscensionis
Sixweeks three-awn
Photo by Chez Brungraber
Family: Poaceae · Type: Grass · Native
Aristida adscensionis (Sixweeks three-awn) is a native California grass in the Poaceae family, recognized by annual habit and equal awns.
Sixweeks three-awn is a native annual grass found in coastal California, the southern Channel Islands, western Transverse Ranges, Peninsular Ranges, and desert regions at elevations below 1,400 meters in disturbed areas, dry open places, and rocky shrublands. Flowering from January to November, this plant produces delicate, pale green to tan flower clusters with distinctive three-part awns. Growing with slender, branched stems 20 to 80 centimeters tall, it spreads in loosely clustered formations. Its narrow leaves are less than 15 centimeters long, tightly rolled into thin, thread-like blades. The plant's seed heads feature asymmetrical glumes and lemmas with three nearly equal awns measuring 7 to 20 millimeters long, creating a distinctive whispy, feathery appearance.
Identification and appearance
Key characters: 10 sympatric species; distinguished by annual habit and equal awns
Habitat and range
Habitat: Disturbed areas, dry, open places, rocky sites, shrubland
Elevation: < 1400 m
California counties: San Diego, San Bernardino, Riverside, Imperial, Orange, San Luis Obispo, Inyo, Los Angeles, Santa Barbara, Ventura, Kern, San Benito, Shasta, Modoc, Humboldt, Santa Cruz, Tulare
Outside California: to Missouri, Texas, South America
Bloom period
Aristida adscensionis blooms Jan-Nov.
How to tell it apart
vs Muhlenbergia: Aristida always has three awns per seed; Muhlenbergia has one awn or none.; vs Hilaria: Aristida has three awns on each spikelet; Hilaria has spikelets grouped in threes with single awns.; vs Bromus: Aristida's three thin straight awns are unmistakable; Bromus has single awns and papery seed coverings.; vs Schismus: Aristida has three long awns per seed; Schismus is a tiny annual with no awns at all.; vs Stipa: Aristida has three straight awns; Stipa has one twisted, bent awn.
Frequently asked questions
Is Aristida adscensionis native to California?
Yes. Aristida adscensionis is native to California (recorded as native).
When does Aristida adscensionis bloom?
Aristida adscensionis blooms Jan-Nov.
Where in California does Aristida adscensionis grow?
Aristida adscensionis occurs in San Diego, San Bernardino, Riverside, Imperial, Orange, San Luis Obispo, Inyo, Los Angeles and other counties, at elevations of < 1400 m.
What plant family does Aristida adscensionis belong to?
Aristida adscensionis is in the Poaceae family, genus Aristida.
What habitat does Aristida adscensionis grow in?
Aristida adscensionis grows in Disturbed areas, dry, open places, rocky sites, shrubland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.