Hazardia detonsa
Island hazardia
(c) Cayman Lanzone, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Shrub · Native
Conservation status: CNPS 4.3
Hazardia detonsa (Island hazardia) is a native California shrub in the Asteraceae family, recognized by largest flower heads with most disk flowers.
Island hazardia is a rare (CNPS 4.3) California native shrub found in northern Channel Islands in open rocky slopes, sea cliffs, coastal scrub, chaparral, and pine woodland at elevations below 450 meters. Flowering from April to November, this plant produces yellow flower heads with ray flowers that can become red-purple, arranged in dense clusters 10 to 13 millimeters wide. Growing 60 to 250 centimeters tall with densely woolly-tomentose stems, it forms a compact shrubby structure. Its thick leaves are 4 to 14 centimeters long, obovate in shape with obtuse tips and slightly serrate edges. The fruit is small, 3 to 4 millimeters long with 4 ribs and hairy surfaces, accompanied by a 6 to 9 millimeter brownish-red pappus.
Identification and appearance
Key characters: 3 sympatric species; largest flower heads with most disk flowers
Habitat and range
Habitat: Open rocky slopes, sea cliffs, coastal scrub, chaparral, pine woodland
Elevation: < 450 m
Bloom period
Hazardia detonsa blooms Apr-Nov.
Conservation status
CNPS 4.3
How to tell it apart
vs Isocoma: Hazardia has toothed leaf margins; Isocoma has entirely smooth-edged leaves.; vs Baccharis: Hazardia has yellow to purple disk flowers; Baccharis has separate male/female plants with whitish flowers.; vs Eriogonum: Hazardia is an Asteraceae shrub with daisy flowers; Eriogonum (Polygonaceae) has ball-like flower clusters.; vs Quercus: Hazardia has daisy flowers and herbaceous leaves; Quercus has acorns and woody oak leaves.; vs Ericameria: Hazardia has toothed leaves and 5-18 female flowers; Ericameria has entire leaves and 0-7 female flowers.
Frequently asked questions
Is Hazardia detonsa native to California?
Yes. Hazardia detonsa is native to California (recorded as native).
When does Hazardia detonsa bloom?
Hazardia detonsa blooms Apr-Nov.
What plant family does Hazardia detonsa belong to?
Hazardia detonsa is in the Asteraceae family, genus Hazardia.
Is Hazardia detonsa rare or endangered?
Hazardia detonsa carries California Rare Plant Rank 4.3, state rank S4.
What habitat does Hazardia detonsa grow in?
Hazardia detonsa grows in Open rocky slopes, sea cliffs, coastal scrub, chaparral, pine woodland.
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.