Rhamnaceae (buckthorn family) Ceanothus

Ceanothus arboreus tree ceanothus

California Channel Islands, Guadalupe Island
Ceanothus ‘Ray Hartmann’, Salvatierra Street. Sairus Patel, 10 Mar 2023
Ceanothus arboreus. From Forest Trees of the Pacific Slope, George B. Sudworth, USDA, 1907

Ceanothus cultivars and hybrids are widely planted as ground cover and shrubs but some can be trees. Look for tree form ‘Ray Hartman’, a hybrid of C. arboreus and C. griseus, at 593 Salvatierra Street; others at Cordura Hall and Forsythe Hall have been removed.

Other campus Ceanothus species and cultivars:

California Garden (Roth and Lomita): Ceanothus thyrsiflorus.

Harmony House addition: Ceanothus gloriosus var. exaltatus ‘Emily Brown’, a small holly-like, opposite leaved groundcover was planted in May 2008. The thick leaves have a single midvein.

Jane Stanford Way along Oval and the top of the quad ears: narrow-leaved ‘Dark Star’ to 5 ft high, and the low, spreading C. griseus horizontalis Yankee Point’.

Jane Stanford Way at Galvez Mall (about 30 yards from Jane Stanford Way on either side of paved walk): C. thyrsiflorus ‘Skylark’ and C. ‘Dark Star’.

Waterwise Demonstration Garden off Raimundo Way: C. ‘Yankee Point’ and C. ‘Ray Hartman’.

Several C. ‘Joyce Coulter’ have been planted (observed 1 May 2006) in the bare spots caused by informal paths through the C.griseus horizontalis at the top of the Oval.

Front of 655 Serra St.: C. ‘Julia Phelps’, a few plants growing with the more numerous ‘Dark Star’. ‘Julia Phelps’ has longer and broader leaves. Only ‘Dark Star’ is planted in the planting strip adjacent to Serra St.

Related material: Stanford Grounds Plant Information Sheet. List No.14, p.2.

About this Entry: The C. arboreus notes are from the book Trees of Stanford and Environs, by Ronald Bracewell, published 2005. John Rawlings authored the rest of the text. Minor edits; entry title reverted to C. arboreus (Jan 2024, SP). Ray Harman locations revised, added to (Jun 2024, SP).