Cleomella hillmanii var. hillmanii
Hillman's cleomella
(c) Matt Berger, some rights reserved (CC BY), uploaded by Matt Berger · licence
Family: Cleomaceae · Type: Annual · Native
Conservation status: CNPS 2B.2
Cleomella hillmanii var. hillmanii (Hillman's cleomella) is a native California annual in the Cleomaceae family, recognized by distinctive large sepals.
Hillman's cleomella is a rare (CNPS 2B.2) California native annual found in the Modoc Plateau in Lassen County's alkaline meadows and flats at elevations of 1,220 to 1,462 meters. Flowering in May, this plant produces small yellow flowers with delicate petals 4 to 8 millimeters long. Growing 5 to 55 centimeters tall with erect, smooth stems that may branch from lower nodes, it forms an elegant upright structure in open meadow environments. Its leaves feature elliptic to ovate leaflets 0.8 to 2.4 centimeters long, carried on slender petioles 2 to 6 centimeters in length. The plant develops narrow capsule fruits 3.5 to 6 millimeters long with distinctive conic valves.
Identification and appearance
Key characters: 4 sympatric species; distinctive large sepals
Habitat and range
Habitat: Alkaline meadows and flats
Elevation: 1220-1462 m
Outside California: to Oregon, Idaho, Nevada
Bloom period
Cleomella hillmanii var. hillmanii blooms May.
Conservation status
CNPS 2B.2
How to tell it apart
vs Physaria: Physaria has inflated bladder-like pods and 4 petals; Cleomella has small flat round capsules and variable petals.; vs Astragalus: Astragalus has compound leaves and pea-shaped flowers; Cleomella has palmately divided leaves and regular flowers.; vs Sesbania: Sesbania has pinnately compound leaves and large pea flowers; Cleomella has palmate leaves and small regular flowers.; vs Atriplex: Atriplex has tiny greenish flowers and simple leaves; Cleomella has showy flowers and palmately divided leaves.; vs Isocoma: Isocoma has yellow composite flower heads; Cleomella has individual flowers with separate petals and prominent stamens.
Frequently asked questions
Is Cleomella hillmanii var. hillmanii native to California?
Yes. Cleomella hillmanii var. hillmanii is native to California (recorded as native).
When does Cleomella hillmanii var. hillmanii bloom?
Cleomella hillmanii var. hillmanii blooms May.
What plant family does Cleomella hillmanii var. hillmanii belong to?
Cleomella hillmanii var. hillmanii is in the Cleomaceae family, genus Cleomella.
Is Cleomella hillmanii var. hillmanii rare or endangered?
Cleomella hillmanii var. hillmanii carries California Rare Plant Rank 2B.2, state rank S2.
What habitat does Cleomella hillmanii var. hillmanii grow in?
Cleomella hillmanii var. hillmanii grows in Alkaline meadows and flats.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.