Xanthisma gracile
Annual bristleweed
(c) Trevor Van Loon, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Conservation status: CNPS 4.3
Xanthisma gracile (Annual bristleweed) is a native California herb in the Asteraceae family.
Annual bristleweed is a native annual herb found in the eastern Mojave Desert in sandy, clay, or rocky desert woodland and scrub habitats at elevations of 900 to 1,550 meters. Flowering from April to September, this plant produces bright yellow ray flowers 7 to 12 millimeters long in delicate heads with white and red-brown bristly edges. Growing with erect, slender stems 3 to 25 centimeters tall that are bristly throughout and branched at or above the base, it has a distinctive open, wispy structure. Its leaves are 1 to 3 centimeters long with 3 to 7 millimeter width, typically pinnately lobed with oblanceolate or elliptic shapes and appressed hairs. The fruit is 2.2 to 2.8 millimeters long, covered in fine white to canescent hairs.
Identification and appearance
Key characters: 0 sympatric species - geographically isolated in e DMoj
Habitat and range
Habitat: Sandy, clay, or rocky places, desert woodland or scrub
Elevation: 900-1550 m
California counties: San Bernardino
Outside California: to Colorado, Texas, northern Mexico
Bloom period
Xanthisma gracile blooms Apr-Sep.
Conservation status
CNPS 4.3
How to tell it apart
vs Heterotheca: Xanthisma leaves have spine-tipped teeth; Heterotheca leaves lack spines and are soft.; vs Stenotus: Xanthisma has spiny-edged leaves; Stenotus has smooth three-veined leaves.; vs Nestotus: Xanthisma leaves are spine-tipped and rigid; Nestotus leaves are smooth and thread-like.; vs Hazardia: Xanthisma upper leaves become scale-like; Hazardia maintains normal leaves throughout.; vs Ericameria: Xanthisma has spine-tipped leaf teeth; Ericameria has smooth narrow thread-like leaves.
Frequently asked questions
Is Xanthisma gracile native to California?
Yes. Xanthisma gracile is native to California (recorded as native).
When does Xanthisma gracile bloom?
Xanthisma gracile blooms Apr-Sep.
Where in California does Xanthisma gracile grow?
Xanthisma gracile occurs in San Bernardino, at elevations of 900-1550 m.
What plant family does Xanthisma gracile belong to?
Xanthisma gracile is in the Asteraceae family, genus Xanthisma.
Is Xanthisma gracile rare or endangered?
Xanthisma gracile carries California Rare Plant Rank 4.3, state rank S4.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.