Horkelia truncata
Ramona horkelia
Photo by Chez Brungraber
Family: Rosaceae · Type: Herb · Native
Conservation status: CNPS 1B.3
Horkelia truncata (Ramona horkelia) is a native California herb in the Rosaceae family, recognized by . Key features: very few but large, heavily-toothed leaflets, large round petals.
Ramona horkelia is a rare (CNPS 1B.3) California native perennial found in the Peninsular Ranges in dry red clay and open chaparral at elevations of 400 to 1,300 meters. Flowering from March to June, this plant produces white petals approximately 5 to 7 millimeters wide and nearly round. Growing with green tufted stems 20 to 60 centimeters tall, it forms a compact clump with distinctive foliage. Its leaves feature 1 to 3 leaflets on each side, with terminal leaflets 10 to 30 millimeters long, oblong to obovate, and generally having more than 20 teeth along the margin. The plant bears an open inflorescence with 5 to 20 flowers, each emerging from pedicels 4 to 20 millimeters long.
Identification and appearance
Key characters: 2 sympatric species. Key features: very few but large, heavily-toothed leaflets, large round petals
Habitat and range
Habitat: dry red clay, open chaparral
Elevation: 400-1300 m
California counties: San Diego
Outside California: northern Baja California
Bloom period
Horkelia truncata blooms Mar-Jun.
Conservation status
CNPS 1B.3
How to tell it apart
vs Drymocallis: Horkelia has exactly 10 stamens and white-pink flowers; Drymocallis has 20+ stamens and yellow-white flowers.; vs Erodium: Horkelia has pinnate leaves and rose-family flowers; Erodium has lobed/divided leaves and long-beaked fruits.; vs Phacelia: Horkelia has rose-family flowers with separate petals; Phacelia has bell-shaped fused corollas with protruding stamens.; vs Potentilla: Horkelia has exactly 10 stamens and flattened filaments; Potentilla has 20+ stamens and thread-like filaments.; vs Ivesia: Horkelia has flat leaves with 2-15 separated leaflets; Ivesia has cylindrical bottlebrush leaves with overlapping leaflets.
Frequently asked questions
Is Horkelia truncata native to California?
Yes. Horkelia truncata is native to California (recorded as native).
When does Horkelia truncata bloom?
Horkelia truncata blooms Mar-Jun.
Where in California does Horkelia truncata grow?
Horkelia truncata occurs in San Diego, at elevations of 400-1300 m.
What plant family does Horkelia truncata belong to?
Horkelia truncata is in the Rosaceae family, genus Horkelia.
Is Horkelia truncata rare or endangered?
Horkelia truncata carries California Rare Plant Rank 1B.3, state rank S3.
Related species
Other California species in the same genus, family, or bioregion.
- Horkelia tularensis — Kern plateau horkelia
- Horkelia wilderae — Barton flats horkelia
- Horkelia yadonii — Santa lucia horkelia
- Horkelia bolanderi — Bolander's horkelia
- Horkelia californica — California horkelia
- Horkelia californica var. californica — California horkelia
- Horkeliella congdonis — Congdon's false horkelia
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.