Calochortus westonii
Shirley meadows star-tulip, Shirley Meadows Star-Tulip
(c) Adam J. Searcy, some rights reserved (CC BY), uploaded by Adam J. Searcy · licence
Family: Liliaceae · Type: Herb · Native
Conservation status: CNPS 1B.2
Calochortus westonii (Shirley meadows star-tulip) is a native California herb in the Liliaceae family, recognized by blue color and distinctive nectary membrane structure are key.
Shirley meadows star-tulip is a rare (CNPS 1B.2) California native perennial found in southern Sierra Nevada Mountains (Greenhorn Mountains) in meadows and open woodland at elevations of 1,500 to 2,000 meters. Flowering from May to June, this plant produces blue to white flowers with lanceolate petals 8 to 12 millimeters long, delicately bell-shaped and sparsely hairy. Growing with slender stems 3 to 15 centimeters tall, it emerges from persistent basal leaves up to 20 centimeters long and bears no cauline leaves. Its single to ten flowers spread in an open, often erect arrangement, with distinctive white to lilac anthers and a nectary bordered by ciliate membranes. The nodding fruit is 10 to 15 millimeters long and distinctly angled.
Identification and appearance
Key characters: 7 sympatric species; blue color and distinctive nectary membrane structure are key
Habitat and range
Habitat: Meadows, open woodland
Elevation: +- 1500-2000 m.
California counties: Kern, Tulare
Bloom period
Calochortus westonii blooms May-Jun.
Conservation status
CNPS 1B.2
How to tell it apart
vs Clarkia: Calochortus has 6 stamens and grass-like leaves; Clarkia has 8 stamens and broad stem leaves.; vs Fritillaria: Calochortus flowers open upward/outward in cups; Fritillaria flowers hang downward like bells.; vs Thismia: Calochortus has green leaves and open flowers; Thismia is leafless with closed tubular flowers.; vs Eschscholzia: Calochortus has 6 petals and parallel-veined leaves; Eschscholzia has 4 petals and divided leaves.; vs Sidalcea: Calochortus has 6 petals and grass-like leaves; Sidalcea has 5 petals and rounded lobed leaves.
Frequently asked questions
Is Calochortus westonii native to California?
Yes. Calochortus westonii is native to California (recorded as native).
When does Calochortus westonii bloom?
Calochortus westonii blooms May-Jun.
Where in California does Calochortus westonii grow?
Calochortus westonii occurs in Kern, Tulare, at elevations of +- 1500-2000 m..
What plant family does Calochortus westonii belong to?
Calochortus westonii is in the Liliaceae family, genus Calochortus.
Is Calochortus westonii rare or endangered?
Calochortus westonii carries California Rare Plant Rank 1B.2, state rank S3.
Related species
Other California species in the same genus, family, or bioregion.
- Calochortus albus — White globe lily
- Calochortus amabilis — Diogenes' lantern
- Calochortus amoenus — Purple fairy lantern
- Calochortus argillosus — Clay mariposa lily
- Calochortus bruneaunis — Bruneau mariposa lily
- Calochortus catalinae — Catalina mariposa lily
- Clintonia andrewsiana — Andrew's clintonia
- Clintonia sp.
- Clintonia uniflora — Bride's bonnet
- Erythronium californicum — California fawn lily
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.