Oncosiphon sp.
Family: Asteraceae · Type: Annual · Not Native
Oncosiphon sp. is a non-native California annual in the Asteraceae family.
How to tell it apart
vs Matricaria: Oncosiphon smells intensely foul and has spherical heads; Matricaria smells sweet (apple-like) and has egg-shaped heads.; vs Cotula: Oncosiphon has intensely pungent odor and spherical heads; Cotula lacks strong odor and has button-like flattened heads.; vs Helenium: Oncosiphon has foul-smelling spherical heads; Helenium has no strong odor and ball-shaped yellow flower centers with drooping rays.; vs Eriophyllum: Oncosiphon smells foul with spherical heads; Eriophyllum has woolly gray foliage and daisy-like yellow flowers.; vs Acamptopappus: Oncosiphon is foul-smelling with ball-like heads; Acamptopappus is a woody shrub with flat-topped yellow flower clusters.
Frequently asked questions
Is Oncosiphon sp. native to California?
No. Oncosiphon sp. is not native to California (recorded as not native).
What plant family does Oncosiphon sp. belong to?
Oncosiphon sp. is in the Asteraceae family, genus Oncosiphon.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-04-14
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.