Agoseris heterophylla var. heterophylla
Annual agoseris
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Family: Asteraceae · Type: Herb · Native
Agoseris heterophylla var. heterophylla (Annual agoseris) is a native California herb in the Asteraceae family, recognized by annual habit and briefly opening flowers diagnostic.
Annual agoseris is a California native annual herb found in the California Floristic Province, including many open habitats at elevations generally below 2,000 meters. Flowering from May to June, this plant produces yellow flowers with narrow ligules 2 to 6 millimeters long that nearly match the height of the flower head. Growing with delicate stems 10 to 30 centimeters tall, it has a slender, upright growth habit. Its leaves feature distinctive lobed edges with 2 to 3 pairs of lobes, ranging from glabrous to densely hairy. The plant produces highly variable fruits with prominent ribs that maintain their structure throughout the fruit's development.
Identification and appearance
Key characters: Co-occurs with 17 species; annual habit and briefly opening flowers diagnostic
Habitat and range
Habitat: Many open habitats
Elevation: generally < 2000 m
Outside California: to British Columbia, Montana, Utah, New Mexico, Baja California, adventive Europe (Sweden)
Bloom period
Agoseris heterophylla var. heterophylla blooms May-Jun.
How to tell it apart
vs Taraxacum: Agoseris bracts graduate gradually in size; Taraxacum has dramatically smaller outer bracts and longer one-sided pappus.; vs Hypochaeris: Agoseris has completely bractless stems; Hypochaeris often has small leafy bracts partway up the stem.; vs Microseris: Agoseris pappus bristles evenly distributed; Microseris has 5-80 white scales (not plume-like bristles).; vs Uropappus: Agoseris has plume-like bristles; Uropappus has 5 large silvery scales alternating with 5 smaller ones.; vs Leontodon: Agoseris has unbranched scapes; Leontodon often has branched stems with multiple heads.
Frequently asked questions
Is Agoseris heterophylla var. heterophylla native to California?
Yes. Agoseris heterophylla var. heterophylla is native to California (recorded as native).
When does Agoseris heterophylla var. heterophylla bloom?
Agoseris heterophylla var. heterophylla blooms May-Jun.
What plant family does Agoseris heterophylla var. heterophylla belong to?
Agoseris heterophylla var. heterophylla is in the Asteraceae family, genus Agoseris.
What habitat does Agoseris heterophylla var. heterophylla grow in?
Agoseris heterophylla var. heterophylla grows in Many open habitats.
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.