Frangula californica subsp. ursina

(Greene) Kartesz & Gandhi

Phytologia 76: 449. 1994.

Common names: Desert hoary coffeeberry
Basionym: Rhamnus ursina Greene Leafl. Bot. Observ. Crit. 1: 63. 1904
Synonyms: Frangula ursina (Greene) Grubov R. californica subsp. ursina (Greene) C. B. Wolf R. californica var. ursina (Greene) McMinn R. castorea Greene R. tomentella subsp. ursina (Greene) J. O. Sawyer
Treatment appears in FNA Volume 12. Treatment on page 55. Mentioned on page 53, 54, 58.

Leaf blades green adaxially, elliptic to ovate, 3–8.5 cm, margins entire to serrulate or serrate with gland-tipped teeth, flat to slightly revolute, apex acute to rounded, abaxial surface densely and closely white stellate-hairy, usually with simple, erect hairs at least along veins (sometimes relatively inconspicuous), adaxial surface nearly glabrous; veins not prominent abaxially. Drupe stones 2.


Phenology: Flowering May–Sep.
Habitat: Chaparral, desert scrub, woodlands.
Elevation: 700–2600 m.

Distribution

V12 348-distribution-map.jpg

Ariz., Calif., Nev., N.Mex., Mexico (Sonora).

Discussion

C. B. Wolf (1938) considered a collection from Cochise County in southeastern Arizona named as Rhamnus blumeri Greene [Frangula ×blumeri (Greene) Kartesz & Gandhi] to be a hybrid between Frangula californica var. ursina and F. betulifolia. Study of an isotype of R. blumeri, and specimens of Wolf 2592 (MO), 2593 (MO), 2595 (MO), and Wolf & Everett 11384 (TEX), essentially corroborate the observations by Wolf. However, from examination of numerous other collections of both species from the Chiricahua Mountains, it appears that hybridization between F. betulifolia and F. californica is not common.

Selected References

None.

Lower Taxa

None.
John O. Sawyer† +  and Guy L. Nesom +
(Greene) Kartesz & Gandhi +
Rhamnus ursina +
Desert hoary coffeeberry +
Ariz. +, Calif. +, Nev. +, N.Mex. +  and Mexico (Sonora). +
700–2600 m. +
Chaparral, desert scrub, woodlands. +
Flowering May–Sep. +
Frangula ursina +, R. californica subsp. ursina +, R. californica var. ursina +, R. castorea +  and R. tomentella subsp. ursina +
Frangula californica subsp. ursina +
Frangula californica +
subspecies +