Horkelia hendersonii
Henderson's horkelia
(c) Dee Shea Himes, some rights reserved (CC BY) · licence
Family: Rosaceae · Type: Herb · Native
Conservation status: CNPS 1B.1
Horkelia hendersonii (Henderson's horkelia) is a native California herb in the Rosaceae family, recognized by no sympatric species.
Henderson's horkelia is a rare (CNPS 1B.1) California native perennial found in the northeastern Klamath Ranges in dry granitic flats at elevations of 2,000 to 2,300 meters. Flowering from July to August, this plant produces white flowers in small, flat-topped clusters with 5 to 20 blooms. Growing as a matted, grayish plant less than 20 centimeters tall, it forms dense, compact patches with distinctive crowded leaflets. Its compound leaves have 5 to 10 wedge-shaped leaflets per side, each 4 to 10 millimeters long with approximately 5 teeth toward the tip, covered in dense hairs. The tiny flowers feature white petals about 3 to 4 millimeters long, set against intricate, hairy hypanthiums 2 to 4 millimeters wide.
Identification and appearance
Key characters: Geographically isolated; no sympatric species
Habitat and range
Habitat: dry granitic flats
Elevation: 2000-2300 m
Outside California: southwestern Oregon (Mount Ashland)
Bloom period
Horkelia hendersonii blooms Jul-Aug.
Conservation status
CNPS 1B.1
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 hendersonii native to California?
Yes. Horkelia hendersonii is native to California (recorded as native).
When does Horkelia hendersonii bloom?
Horkelia hendersonii blooms Jul-Aug.
What plant family does Horkelia hendersonii belong to?
Horkelia hendersonii is in the Rosaceae family, genus Horkelia.
Is Horkelia hendersonii rare or endangered?
Horkelia hendersonii carries California Rare Plant Rank 1B.1, state rank S1.
What habitat does Horkelia hendersonii grow in?
Horkelia hendersonii grows in dry granitic flats.
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.