Ceanothus prostratus var. occidentalis

McMinn

in M. van Rensselaer and H. McMinn, Ceanothus, 262. 1942.

Common names: Cobb Mountain ceanothus
EndemicConservation concern
Synonyms: Ceanothus divergens subsp. occidentalis (McMinn) Abrams
Treatment appears in FNA Volume 12. Treatment on page 105. Mentioned on page 104.

Shrubs, 0.1–0.3 m, matlike to moundlike. Stems prostrate, spreading, or ascending. Leaf blades slightly folded lengthwise adaxially, margins ± wavy, teeth 5–9. Capsule horns spreading, not conspicuously rugose. 2n = 24.


Phenology: Flowering Apr–May.
Habitat: Gravelly or rocky soils derived from volcanic substrates, open flats and ridges, conifer forests.
Elevation: 800–1400 m.

Discussion

Variety occidentalis is known from only a few localities in the mountains of Lake, Mendocino, Napa, and Sonoma counties. L. Abrams and R. S. Ferris (1923–1960, vol. 3) treated it as part of Ceanothus divergens, based partly on leaf morphology, but its life form and fruit morphology suggest a closer relationship to C. prostratus.

Selected References

None.

Lower Taxa

None.
Clifford L. Schmidt† +  and Dieter H. Wilken +
McMinn +
Ceanothus sect. Cerastes +
Cobb Mountain ceanothus +
800–1400 m. +
Gravelly or rocky soils derived from volcanic substrates, open flats and ridges, conifer forests. +
Flowering Apr–May. +
in M. van Rensselaer and H. McMinn, Ceanothus, +
Endemic +  and Conservation concern +
Ceanothus divergens subsp. occidentalis +
Ceanothus prostratus var. occidentalis +
Ceanothus prostratus +
variety +