Phacelia peirsoniana
Peirson's phacelia, Peirson's Phacelia
(c) Martin Purdy, some rights reserved (CC BY), uploaded by Martin Purdy · licence
Family: Hydrophyllaceae · Type: Herb · Native
Conservation status: CNPS 4.3
Phacelia peirsoniana (Peirson's phacelia) is a native California herb in the Hydrophyllaceae family, recognized by scales free from filaments diagnostic.
Peirson's phacelia is a California native annual herb found in northern Owens Valley in rocky slopes, sagebrush scrub, and pinyon/juniper woodland at elevations of 1,500 to 2,700 meters. Flowering from May to June, this plant produces delicate white to violet flowers in narrowly bell-shaped clusters 4 to 6 millimeters long. Growing with erect stems 4 to 30 centimeters tall, it has a simple to branched structure with sparse short stiff hairs and a subtle aromatic quality. Its leaves are rounded, 10 to 60 millimeters long, with crenate or irregular tooth edges, typically shorter than their petioles. The fruit contains 20 to 50 small pitted seeds, each approximately 1 millimeter long.
Identification and appearance
Key characters: 23 sympatric species; scales free from filaments diagnostic
Habitat and range
Habitat: Rocky slopes, canyons, sagebrush scrub, pinyon/juniper woodland
Elevation: 1500-2700 m
Outside California: western Nevada
Bloom period
Phacelia peirsoniana blooms May-Jun.
Conservation status
CNPS 4.3
How to tell it apart
vs Nemophila: Phacelia has flowers in coiled scorpion-tail clusters; Nemophila has solitary showy flowers at leaf axils.; vs Eucrypta: Phacelia is typically non-sticky with seeds that fall out cleanly; Eucrypta feels very sticky and retains 1-2 seeds in fruit.; vs Pholistoma: Phacelia has coiled flower clusters; Pholistoma has flowers scattered along stems with backward-pointing stem bristles.; vs Echium: Phacelia has coiled clusters of small flowers; Echium has large showy blue-purple flowers in tall spike-like clusters.; vs Gilia: Phacelia has coiled flower clusters and bristly foliage; Gilia has flowers in round heads or loose clusters with smoother foliage.
Frequently asked questions
Is Phacelia peirsoniana native to California?
Yes. Phacelia peirsoniana is native to California (recorded as native).
When does Phacelia peirsoniana bloom?
Phacelia peirsoniana blooms May-Jun.
What plant family does Phacelia peirsoniana belong to?
Phacelia peirsoniana is in the Hydrophyllaceae family, genus Phacelia.
Is Phacelia peirsoniana rare or endangered?
Phacelia peirsoniana carries California Rare Plant Rank 4.3, state rank S4.
What habitat does Phacelia peirsoniana grow in?
Phacelia peirsoniana grows in Rocky slopes, canyons, sagebrush scrub, pinyon/juniper 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.