Streptanthus polygaloides subsp. undulatus
Pine flat jewelflower
Photo: parent species Streptanthus polygaloides · (c) Ken-ichi Ueda, some rights reserved (CC BY) · licence
Family: Brassicaceae · Type: Annual · Native
Streptanthus polygaloides subsp. undulatus (Pine flat jewelflower) is a native California annual in the Brassicaceae family, recognized by wavy sepal margins and papillate texture.
Pine flat jewelflower is a California native annual found in central coastal California in serpentine grasslands and blue oak woodlands at elevations of 200 to 725 meters. Flowering in June, this plant produces pale yellow to golden yellow flowers with distinctively wavy margins and unique petal shapes. Growing with delicate stems typical of annual wildflowers, it emerges in scattered clusters among serpentine rock outcrops. Its leaves are characteristic of the jewelflower genus, with subtle variations in shape and arrangement that help it blend into its specialized habitat. The flower's pale yellow sepals have distinctive wavy margins and short bristly surfaces, creating an intricate and delicate botanical display.
Identification and appearance
Key characters: 22 sympatric species; key features are wavy sepal margins and papillate texture
Habitat and range
Habitat: Serpentine outcrops and roadcuts, in grassland and blue oak woodland
Elevation: 200-725 m
Bloom period
Streptanthus polygaloides subsp. undulatus blooms Jun.
How to tell it apart
vs Caulanthus: Seed pods are flattened like sword blades versus cylindrical tubes in Caulanthus.; vs Boechera: Robust plants often over 2.5 feet with large flowers (sepals 4-8mm) versus more delicate habit.; vs Claytonia: Mustard family with 4 petals and 6 stamens versus Claytonia with 5 petals.; vs Silene: Mustard family with seed pods versus Silene with inflated capsules and opposite leaves.; vs Lonicera: Herbaceous mustard with alternate leaves versus woody vine with opposite leaves.
Frequently asked questions
Is Streptanthus polygaloides subsp. undulatus native to California?
Yes. Streptanthus polygaloides subsp. undulatus is native to California (recorded as native).
When does Streptanthus polygaloides subsp. undulatus bloom?
Streptanthus polygaloides subsp. undulatus blooms Jun.
What plant family does Streptanthus polygaloides subsp. undulatus belong to?
Streptanthus polygaloides subsp. undulatus is in the Brassicaceae family, genus Streptanthus.
What habitat does Streptanthus polygaloides subsp. undulatus grow in?
Streptanthus polygaloides subsp. undulatus grows in Serpentine outcrops and roadcuts, in grassland and blue oak woodland.
Related species
Other California species in the same genus, family, or bioregion.
- Streptanthus sp. — Jewelflower
- Streptanthus tortuosus — Mountain jewelflower
- Streptanthus tortuosus subsp. truei — True's mountain jewelflower
- Streptanthus tortuosus var. foliosus — Wawona jewelflower
- Streptanthus tortuosus var. oblongus — Klamath mountains jewelflower
- Streptanthus tortuosus var. optatus — Sierran foothill jewelflower
Sources: Jepson eFlora · CalPhotos
Last updated 2026-09-15
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.