Caulanthus anceps
Lemmon's mustard
(c) marlin harms, some rights reserved (CC BY) · licence
Family: Brassicaceae · Type: Herb · Native
Caulanthus anceps (Lemmon's mustard) is a native California herb in the Brassicaceae family, recognized by spreading petals without wavy margins distinguish it from similar species.
Lemmon's mustard is a California native annual herb found in southern Sierra Nevada Foothills, southwestern San Joaquin Valley, southeastern Coast Ranges, and western Transverse Ranges on slopes, plains, and roadsides at elevations of 300 to 1,700 meters. Flowering from March to May, this plant produces white to lavender flowers 4 to 8 millimeters long with spreading petals. Growing with erect stems 35 to 150 centimeters tall, it can be simple or branched toward the top and is sparsely to densely hairy. Its cauline leaves are petioled, 2 to 13 centimeters long, lanceolate to oblong with toothed edges. The fruit is an ascending to reflexed pod 3 to 6.7 centimeters long, containing 40 to 54 small oblong seeds.
Identification and appearance
Key characters: 9 sympatric species; spreading petals without wavy margins distinguish it from similar species
Habitat and range
Habitat: Slopes, plains, roadsides, alkaline or not, vertic clay, rarely serpentine
Elevation: 300-1700 m
California counties: Kern, San Benito, San Luis Obispo, Ventura, Monterey, Santa Barbara, Stanislaus, Fresno, Los Angeles, Kings
Bloom period
Caulanthus anceps blooms Mar-May.
How to tell it apart
vs Streptanthus: Seed pods are cylindrical and round versus flattened blade-like pods in Streptanthus.; vs Sisymbrium: Petals are distinctively crinkled and papery versus smooth petals in Sisymbrium.; vs Hirschfeldia: Young pods reflex sharply downward versus pointing upward or outward.; vs Boechera: Pods reflex downward and contain wingless seeds versus erect pods with winged seeds.; vs Brassica: Young seed pods bend sharply downward versus pointing upward in Brassica.
Frequently asked questions
Is Caulanthus anceps native to California?
Yes. Caulanthus anceps is native to California (recorded as native).
When does Caulanthus anceps bloom?
Caulanthus anceps blooms Mar-May.
Where in California does Caulanthus anceps grow?
Caulanthus anceps occurs in Kern, San Benito, San Luis Obispo, Ventura, Monterey, Santa Barbara, Stanislaus, Fresno and other counties, at elevations of 300-1700 m.
What plant family does Caulanthus anceps belong to?
Caulanthus anceps is in the Brassicaceae family, genus Caulanthus.
What habitat does Caulanthus anceps grow in?
Caulanthus anceps grows in Slopes, plains, roadsides, alkaline or not, vertic clay, rarely serpentine.
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.