Frangula californica subsp. cuspidata

(Greene) Kartesz & Gandhi

Phytologia 76: 449. 1994.

Endemic
Basionym: Rhamnus cuspidata Greene Leafl. Bot. Observ. Crit. 1: 64. 1904
Synonyms: Frangula viridula (Jepson) Grubov R. californica subsp. cuspidata (Greene) C. B. Wolf R. californica var. viridula Jepson R. tomentella subsp. cuspidata (Greene) J. O. Sawyer
Treatment appears in FNA Volume 12. Treatment on page 55. Mentioned on page 53, 54, 56.

Leaf blades green adaxially, elliptic, 2–5(–6) cm, margins sharply serrate to dentate-serrulate with gland-tipped teeth, sometimes strongly revolute, apex abruptly acuminate to acute, abaxial surface sparsely to moderately densely white stellate-hairy, with intermixed longer, simple, erect hairs at least along veins, adaxial surface glabrous or sparsely hirsutulous; veins not prominent abaxially. Drupe stones 2.


Phenology: Flowering Apr–Jun.
Habitat: Chaparral, desert scrub, montane woodlands.
Elevation: 400–2300 m.

Discussion

When present, the strongly revolute leaf margins of subsp. cuspidata contrast with those of other taxa of Frangula californica. Plants identifiable as subsp. cuspidata but with flat-margined leaves perhaps show the influence of subsp. tomentella.

Selected References

None.

Lower Taxa

None.
John O. Sawyer† +  and Guy L. Nesom +
(Greene) Kartesz & Gandhi +
Rhamnus cuspidata +
400–2300 m. +
Chaparral, desert scrub, montane woodlands. +
Flowering Apr–Jun. +
Frangula viridula +, R. californica subsp. cuspidata +, R. californica var. viridula +  and R. tomentella subsp. cuspidata +
Frangula californica subsp. cuspidata +
Frangula californica +
subspecies +