Senecio flaccidus
Threadleaf ragwort, Threadleaf Ragwort
Photo by Chez Brungraber
Family: Asteraceae · Type: Subshrub · Native
Senecio flaccidus (Threadleaf ragwort) is a native California subshrub in the Asteraceae family, recognized by Shrubby ragwort w/ woody taproot; narrowly thread-like leaves or linear-lobed.
Threadleaf ragwort is a California native shrub found in desert and southwestern mountain regions in dry, rocky habitats at elevations ranging from 100 to 1,500 meters. Flowering from March to October, this plant produces yellow ray flowers 10 to 15 millimeters long in clusters of 5 to 10 heads. Growing 3 to 12 meters tall with erect or arching stems that are glabrous or slightly woolly, it develops from a woody taproot. Its leaves are distinctively narrow and thread-like, ranging 3 to 10 centimeters long, either entirely linear or divided into slender, entire lobes. The fruit is covered in dense hair, giving the plant a soft, textured appearance.
Identification and appearance
Key characters: Shrubby ragwort w/ woody taproot; narrowly thread-like leaves or linear-lobed
How to tell it apart
vs Packera: Senecio has larger leaves (over 2.5 inches) and often black-tipped bracts; Packera has tiny leaves (under 1.5 inches) with green or reddish tips.; vs Sonchus: Senecio has yellow daisy flowers with a neat single row of bracts; Sonchus has dandelion-like flowers and milky sap when broken.; vs Dudleya: Senecio is in the sunflower family with daisy flowers; Dudleya is a succulent with thick fleshy leaves and star-shaped flowers.; vs Ericameria: Senecio has one main row of equal bracts around flower heads; Ericameria has 2-4 overlapping rows of unequal bracts.; vs Taraxacum: Senecio has branching stems with multiple flower heads; Taraxacum has leafless hollow stems with single dandelion-like heads.
Frequently asked questions
Is Senecio flaccidus native to California?
Yes. Senecio flaccidus is native to California (recorded as native).
What plant family does Senecio flaccidus belong to?
Senecio flaccidus is in the Asteraceae family, genus Senecio.
Related species
Other California species in the same genus, family, or bioregion.
- Senecio flaccidus var. douglasii — Douglas' threadleaf ragwort
- Senecio flaccidus var. monoensis — Smooth threadleaf ragwort
- Senecio fremontii — Dwarf Mountain Ragwort
- Senecio fremontii var. fremontii — Dwarf mountain ragwort
- Senecio fremontii var. occidentalis — Western dwarf mountain ragwort
- Senecio glomeratus — Cutleaf burnweed
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.