Arnica longifolia
Spearleaf arnica, Spearleaf Arnica
(c) Jim Morefield, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Arnica longifolia (Spearleaf arnica) is a native California herb in the Asteraceae family, recognized by fused basal leaves and colony-forming habit.
Spearleaf arnica is a California native perennial found in the Klamath Ranges, southern North Coast Ranges, Cascade Range, Sierra Nevada, and Great Basin in wet meadows, late snow-melt areas, and open conifer forests at elevations of 1,300 to 3,500 meters. Flowering from July to August, this plant produces yellow ray flowers 10 to 20 millimeters long with radiate heads in clusters of 3 to 20. Growing 30 to 60 centimeters tall with clustered stems that often form large patches, it emerges from a caudex-like rhizome and is slightly sticky and short-hairy. Its leaves are primarily cauline with 5 to 7 pairs, often with the proximal pairs fused around the stem, featuring lanceolate blades 5 to 12 centimeters long that are nearly entire. The plant produces fruits 3 to 7 millimeters long with a yellow-brown to brown pappus that is short-barbed or nearly plumose.
Identification and appearance
Key characters: 16 sympatric species; fused basal leaves and colony-forming habit are diagnostic
Habitat and range
Habitat: Generally wet meadows, late snow-melt areas, or open conifer forest
Elevation: 1300-3500 m
Outside California: to western Canada, Montana, Colorado
Bloom period
Arnica longifolia blooms Jul-Aug.
How to tell it apart
vs Senecio: Senecio has alternate leaves; Arnica leaves opposite in pairs - check leaf arrangement first; vs Wyethia: Wyethia has large basal leaves and many-ranked bracts; Arnica stem leaves opposite, bracts in 2 series; vs Packera: Packera has alternate leaves; Arnica leaves opposite in pairs up stem; vs Kyhosia: Kyhosia has alternate leaves; Arnica leaves opposite - check where leaves attach to stem; vs Helianthella: Helianthella leaves mostly alternate; Arnica leaves strictly opposite in pairs
Frequently asked questions
Is Arnica longifolia native to California?
Yes. Arnica longifolia is native to California (recorded as native).
When does Arnica longifolia bloom?
Arnica longifolia blooms Jul-Aug.
What plant family does Arnica longifolia belong to?
Arnica longifolia is in the Asteraceae family, genus Arnica.
What habitat does Arnica longifolia grow in?
Arnica longifolia grows in Generally wet meadows, late snow-melt areas, or open conifer forest.
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.