Erect, evergreen shrubs, or small trees to 6 (-9) m tall and 0.3 m DBH, capable of stump-sprouting, lignotuber to 1.3 m in diam. sometimes present; bark peeling to shredding, gray to reddish; young twigs gray-tomentose. Leaves coriaceous, lance-elliptic to elliptic to obovate or broadly ovate, 3-12.8 x 1-4.2 cm, (to 14.9 x 8.1 cm on sucker shoots), basally tapering to cuneate, apically obtuse to acute, marginally plane to strongly revolute, serrate to serrulate or rarely subentire, upper surface green and shining, glabrous or with some pubescence along the midvein, lower surface densely gray-tomentose or rarely subglabrous; petioles 2-20 mm long, gray-tomentose. Inflorescences racemose, solitary or clustered, 3.5-14.0 cm long; rachis, pedicels, bracts, bracteoles and calyx gray-tomentose, canescent or more rarely with stalked swollen-headed glandular trichomes; floral bracts lance-linear to oblanceolate to oblong-ovate, plane to navicular, 2-10 mm long; pedicels often curved, 5-20 mm long; bracteoles basal or rarely higher on the pedicel, often reduced, acicular to lanceolate, to 3 mm long. Flowers: calyx lobes subulate to lanceolate, 2-3.5 x 0.8-1.7 mm, acute to acuminate, gray-tomentose, rarely with glandular trichomes; corollas 5-8 x 3.5-5.5 mm, glabrous or puberulent, white, lobes obtuse, 0.9-1.3 x 1.4-1.8 mm; stamens 2.6-3.6 mm long; filaments 2.3-3.4 mm long, villous; anthers 1.0-1.6 mm long, the spurs 0.6-1.1 mm long; ovary villous; style 3.0-5.3 mm long, glabrous to pubescent. Fruit red at maturity, 5-7 in diam.; seeds 2.2-2.3 x 1-1.4 mm, surface broadly reticulate; n=13 (Hagerup, 1928).
Distribution. Baja California (Mexico) to the Santa Monica Mts. in S Santa Barbara Co., California, U.S.A., in areas of mediterranean climate (Raven, 1973) in woodland (Thorne, 1967), and chaparral vegetation, at elevations from near sea level to ca. 600 m. It is the only species in the genus to occur entirely outside the neotropics. Flowering (Jan-)Mar-Jul; fruiting (Mar-)May-Sep (-Oct).
Local names. U.S.A.: California: mock arbute (Jepson, 1839; McMinn, 1939), mock arbutus (Schmidt, 1980b), summer holly (Munz, 1950).
Uses. Widely cultivated (Raven, 1966), and is the only species in the genus commonly used horticulturally. McMinn (1949), Munz (1950), and Schmidt (1980a) give detailed discussions of horticultural considerations.
Key to the Subspecies of Comarostaphylis diversifolia
1. Leaves revolute; inflorescences 3.5-8 cm long; San Diego Co.,
Calif. and N Baja Calif ..................................
subsp. diversifolia
1. Leaves plane; inflorescences 6-14 cm long; Santa Barbara &
Los
Angeles Cos., Calif. ..........................................
subsp. planifolia
Comarostaphylis diversifolia (Parry) Greene subsp. diversifolia. Arctostaphylos arguta (Zuccarini) A. P. de Candolle var. diversifolia Parry, Proc. Davenport Acad. Nat. Sci. 4: 35. 1884. Arctostaphylos diversifolia (Parry) Parry ex Gray, Syn. fl. N. Amer. ed. 2, 2(1): 397. 1886. Type. USA. California: San Diego Co., Jamul Valley, 1878, Sanford s.n. (lectotype, designated by Diggs (1995): UC, photo, Diggs neg. 14).
Leaves narrowly lanceolate, elliptic to ovate, 3-12.8 x 1-4.2 cm, (to 14.9 x 8.0.1 cm on sucker shoots), usually strongly revolute. Inflorescences 3.5-8 cm long, gray-tomentose or rarely with glandular trichomes; floral bracts lance-linear to lance-ovate, nearly plane to subnavicular, 2-7 mm long; pedicels 4-8.5 mm long. Flowers: calyx lobes gray tomentose to rarely glandular.
Distribution. Endemic to Baja California (Mexico),
in chaparral vegetation, from near sea level to ca. 550 m. Flowering
and fruiting Mar-Jun, (Mar-)Jun-Sep respectively.
Comarostaphylis diversifolia (Parry) Greene subsp. planifolia (Jepson) G. Wallace in Thorne, Aliso 9: 191. 1978. Comarostaphylis diversifolia var. planifolia Jepson, Fl. Calif. 3: 29. 1939. Type. USA. California: Santa Catalina Island, Swain Cañon, 13 Jul 1908 (fr), Jepson 3064 (holotype: JEPS, photo, Diggs neg. 15).
Leaves broadly elliptic to obovate or broadly ovate, 3-9 x 1-3.5 cm, usually plane. Inflorescences 6-14 cm long, gray-tomentose, without glandular trichomes; floral bracts lance-ovate to oblong-ovate, navicular, 3-10 mm long; pedicels 5-20 mm long. Flowers: calyx lobes gray-tomentose, non-glandular.
Distribution. Endemic in Los Angeles and Santa
Barbara Counties, California, U.S.A., in chaparral, oak woodland, and closed-cone
pine forests, at elevations from near sea level to ca. 600 m. Flowering
and fruiting (Jan-)Mar-Jul, (Apr-)May-Sep(-Oct), respectively.