Rhamnus ilicifolia |
Rhamnus crocea |
|
---|---|---|
evergreen buckthorn, holly leaf redberry, redberry |
hollyleaf buckthorn, redberry, redberry buckthorn, spiny redberry |
|
Habit | Shrubs or small trees, 1–4 m, unarmed. | Shrubs, 1.2–2(–4) m, usually armed with thorns. |
Branchlets | gray, stiff, glabrous or densely and softly hirtellous. |
reddish to red-purple or orange-brown; glabrous. |
Leaves | persistent, alternate; petiole 2–10 mm; blade usually dull green, sometimes reddish brown, abaxially, glossy to dull green adaxially, broadly elliptic to oblong, orbiculate, or ovate, 2–4.5 cm, distinctly coriaceous, base cuneate to nearly truncate, margins spinulose to spinose-dentate, apex rounded or obtuse to truncate or emarginate, both surfaces glabrous; secondary veins 5–7 pairs, all diverging at nearly same angle. |
persistent, alternate; petiole 2–6 mm; blade usually dull green abaxially, shiny dark green adaxially, elliptic to obovate or ovate, 0.7–2 cm, distinctly coriaceous, base cuneate to truncate, margins coarsely serrate, spinulose-serrulate, or entire, apex obtuse to emarginate, both surfaces glabrous; secondary veins 5–7 pairs, all diverging at nearly same angle. |
Inflorescences | fascicles or flowers solitary. |
fascicles or flowers solitary. |
Pedicels | 2–4 mm. |
2–3 mm. |
Drupes | red, globose, 4–6(–8) mm; stones 2. |
red, globose, 5–8 mm; stones 2. |
Sepals | 4. |
4(–5). |
Petals | 0. |
0. |
2n | = 24. |
|
Rhamnus ilicifolia |
Rhamnus crocea |
|
Phenology | Flowering Jan–Jun. | Flowering (Jan–)Mar–May. |
Habitat | Canyon slopes and bottoms, rock faces, open hillsides, sandstone ridges, serpentine slopes, roadsides, stream benches, riparian areas, meadows, coastal sage scrub, chaparral/desert transition, chaparral, woodlands, montane forests. | Dry washes and canyons, coastal and inland dunes, alluvial fans, gravel flood plains, disturbed sandy flats, brushy slopes, steep granitic slopes, woodlands, coastal sage scrub, chaparral. |
Elevation | 100–2200(–2400) m. (300–7200(–7900) ft.) | 50–1200 m. (200–3900 ft.) |
Distribution |
AZ; CA; NV; OR; Mexico (Baja California)
|
CA
|
Discussion | Rhamnus crocea and closely related species were considered conspecific by C. B. Wolf (1938), who treated those in the flora area as subspp. crocea, ilicifolia, pilosa, and pirifolia; he also recognized subsp. insula (Kellogg) C. B. Wolf from Mexico (Baja California). The taxa are distinctive, but intermediates exist. Wolf identified R. crocea/ilicifolia intermediates from Marin County to the California/Mexico boundary, and R. ilicifolia/insula, R. crocea/pilosa, and R. ilicifolia/pilosa intermediates in southern California, especially in San Diego County. Arizona plants (Pima County, especially in the Ajo Mountains) identified as Rhamnus crocea (for example, K. Christie 2006) appear to be populational variants of the single species present there, R. ilicifolia (R. Felger, pers. comm.). In California, where the two are sympatric over a relatively broad region, R. crocea is distinct from R. ilicifolia in usually bearing thorns and in having smaller leaves with less spinulose margins. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 12, p. 48. | FNA vol. 12, p. 47. |
Parent taxa | Rhamnaceae > Rhamnus | Rhamnaceae > Rhamnus |
Sibling taxa | ||
Synonyms | R. crocea subsp. ilicifolia, R. crocea var. ilicifolia | |
Name authority | Kellogg: Proc. Calif. Acad. Sci. 2: 37. (1863) — (as ilicifolius) | Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 261. (1838) — (as croceus) |
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