Ceanothus pumilus
Siskiyou mat, Siskiyou Mat
(c) Nolan Exe, some rights reserved (CC BY) · licence
Family: Rhamnaceae · Type: Shrub · Native
Ceanothus pumilus (Siskiyou mat) is a native California shrub in the Rhamnaceae family, recognized by small leaves with truncate tips and serpentine habitat.
Siskiyou mat is a California native shrub found in the Klamath Ranges and northern Coast Ranges on serpentine slopes, open flats, chaparral, and conifer forest at elevations of 180 to 2,290 meters. Flowering from April to June, this plant produces pale blue or lavender flowers in compact umbel-like clusters about 1 to 1.5 centimeters long. Growing as a dense, low mat-like shrub less than 0.5 meters tall with occasionally rooting stems and red to gray-brown twigs, it forms a compact ground-covering shape. Its opposite evergreen leaves are oblanceolate to obovate-oblong, 5 to 15 millimeters long, dull green on top, with a pale underside covered in short strigose hairs and thick margins with 2 to 3 teeth near the truncate tip. The fruit is approximately 4 to 6 millimeters wide with slight ridges and very short horns.
Identification and appearance
Key characters: 34 sympatric species; key features are small leaves with truncate tips and serpentine habitat
Habitat and range
Habitat: Generally serpentine, slopes, open flats, chaparral, conifer forest
Elevation: 180-2290 m
California counties: Mendocino, Del Norte, Trinity, Humboldt, El Dorado, Plumas, Siskiyou, Nevada, Placer, Modoc, Shasta
Outside California: southwestern Oregon
Bloom period
Ceanothus pumilus blooms Apr-Jun.
How to tell it apart
vs Rhamnus: Ceanothus has showy blue/white/pink flowers in dense clusters; Rhamnus has tiny inconspicuous greenish flowers.; vs Quercus: Ceanothus has showy flower clusters and small leaves; Quercus has acorns and distinctive lobed or toothed oak leaves.; vs Baccharis: Ceanothus has individual flowers with 5 separate petals; Baccharis has composite flower heads with tiny disc flowers.; vs Cercocarpus: Ceanothus has blue/white/pink flowers in clusters; Cercocarpus has tiny flowers with no petals and feathery fruiting tails.; vs Adenostoma: Ceanothus flowers have 5 distinct colored petals; Adenostoma has tiny white flowers and needle-like clustered leaves.
Frequently asked questions
Is Ceanothus pumilus native to California?
Yes. Ceanothus pumilus is native to California (recorded as native).
When does Ceanothus pumilus bloom?
Ceanothus pumilus blooms Apr-Jun.
Where in California does Ceanothus pumilus grow?
Ceanothus pumilus occurs in Mendocino, Del Norte, Trinity, Humboldt, El Dorado, Plumas, Siskiyou, Nevada and other counties, at elevations of 180-2290 m.
What plant family does Ceanothus pumilus belong to?
Ceanothus pumilus is in the Rhamnaceae family, genus Ceanothus.
What habitat does Ceanothus pumilus grow in?
Ceanothus pumilus grows in Generally serpentine, slopes, open flats, chaparral, conifer forest.
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.