Erigeron filifolius
Thread-leaf fleabane
(c) Steve Matson, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Erigeron filifolius (Thread-leaf fleabane) is a native California herb in the Asteraceae family, recognized by thread-like leaves diagnostic.
Thread-leaf fleabane is a California native perennial found in the high northern California Mountains and Modoc Plateau in sagebrush scrub and juniper to yellow-pine woodland at elevations of 1,200 to 2,000 meters. Flowering from May to August, this plant produces white to lavender or blue flowers with ray petals 4 to 10 millimeters long, arranged in small clusters of 1 to 5 heads. Growing 15 to 30 centimeters tall with a slender-branched caudex, the plant has stems with sparse white upward-curving hairs. Its basal leaves are thread-like to linear, 2 to 7 centimeters long and somewhat stiff-hairy, with cauline leaves restricted to the lower stem. The fruit is characterized by 20 to 30 pappus bristles that help disperse its seeds.
Identification and appearance
Key characters: 30 sympatric species; thread-like leaves diagnostic
Habitat and range
Habitat: Sagebrush scrub, juniper to yellow-pine woodland
Elevation: 1200-2000 m
Outside California: to British Columbia, Montana, Utah
Bloom period
Erigeron filifolius blooms May-Aug.
How to tell it apart
vs Bellis: Erigeron has double-layered pappus (outer scales + inner bristles); Bellis completely lacks pappus.; vs Symphyotrichum: Erigeron has double pappus (2 layers); Symphyotrichum has single layer of uniform bristles.; vs Corethrogyne: Erigeron has simple unbranched stems; Corethrogyne has branched stems.; vs Pseudognaphalium: Erigeron has flat button-like flower heads; Pseudognaphalium has woolly clustered heads without rays.; vs Artemisia: Erigeron has obvious ray petals around yellow disk; Artemisia lacks ray petals entirely.
Frequently asked questions
Is Erigeron filifolius native to California?
Yes. Erigeron filifolius is native to California (recorded as native).
When does Erigeron filifolius bloom?
Erigeron filifolius blooms May-Aug.
What plant family does Erigeron filifolius belong to?
Erigeron filifolius is in the Asteraceae family, genus Erigeron.
What habitat does Erigeron filifolius grow in?
Erigeron filifolius grows in Sagebrush scrub, juniper to yellow-pine woodland.
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.