Sorbus aucuparia
Sorbus californica
European mountain-ash, rowan, rowan-berry, sorbier des oiseaux, sorbier des oiseleurs
California Mountain Ashe, California mountain-ash
1–3(or 4);
bark gray to bronze;
winter buds purple, ovoid to ovoid-conic, 5–15 mm, dull, not glutinous, usually densely villous, hairs whitish, rarely rufous, outer scales sometimes merely ciliate.
1–8;
bark dark gray;
winter buds red to brown, shiny, conic, 5–12 mm, slightly glutinous, sparsely hairy except along scale margins and apex, hairs rufous.
pinnately compound;
stipules deciduous or persistent, whitish-villous or glabrate;
blade paler or often whitish abaxially, dull green to bluish green adaxially, leaflets 11–17(–19), opposite, oblong to oblong-lanceolate or oblanceolate, (2.5–)3–6(–7.5) × 1.5–2 cm, l/w ratio 2.4–3.7, margins serrate at least in distal 1/2, often almost to base, apex acute to obtuse, abaxial surface white-tomentose to villous at flowering, indument often persisting, at least along midveins, leaflet axils, and petiole bases, hairs usually whitish, sometimes rufous.
pinnately compound;
stipules often persistent, margins rufous-hairy;
blade pale abaxially, shiny, green adaxially, leaflets 7–9(–11), opposite or subopposite, oblong to elliptic, sometimes narrowly elliptic, 2.5–4.1(–4.5) × 0.9–2 cm, l/w ratio 2.1–2.6, margins finely to coarsely serrate, sometimes doubly serrate, apex obtuse to acute, surfaces soon glabrous, leaflet axils and petiole bases hairy, hairs rufous.
75–200+-flowered, flat-topped or rounded, 6–18 cm diam.;
peduncles ± whitish-villous.
25–120+-flowered, rounded, 3–11 cm diam.;
peduncles glabrous or sparsely hairy.
densely whitish-villous.
glabrous or sparsely hairy; fruiting pedicels essentially glabrous.
8–11 mm diam.;
hypanthium densely villous, hairs whitish, hypanthium plus sepals 2.9–3.2 mm;
sepals 0.5–1 mm, margins often glandular;
petals white, orbiculate, (3–)4–5 mm;
stamens 15–20;
carpels 1/2 adnate to hypanthium, apex conic, styles 3 or 4, 1.5–3 mm.
9–10 mm diam.;
hypanthium glabrous, hypanthium plus sepals 3 mm;
sepals 0.7–1.5 mm, margins ciliolate, hairs whitish, irregularly glandular;
petals white, broadly ovate, 3–4 mm;
stamens 20;
carpels distinct, apex conic, styles 3 or 4, 1.5–2 mm.
glabrous or densely villous.
glabrous or nearly so.
yellow or orange-red to red, globose to subglobose, 8–12 mm diam., shiny or dull, slightly glaucous or not;
sepals inconspicuous, incurved.
bright red, globose to subglobose, 6–9 mm diam., shiny if glaucous layer is rubbed off;
sepals inconspicuous, incurved.
brown, ovoid to ovoid-lanceoloid, 3–4.5 × 1.5–2 mm, asymmetric, slightly flattened.
red-brown, lanceolate, 4 × 2 mm, slightly asymmetric, slightly flattened.
= 34.
Sorbus aucuparia
Sorbus californica
Sorbus aucuparia is a commonly planted ornamental tree that is widely bird-disseminated. The species is often confused with S. decora, from which it differs by its ovoid and usually densely whitish-villous and nonglutinous winter buds and by its densely villous flowering pedicels and hypanthia. The leaflets of S. aucuparia are often tomentose abaxially at flowering; those of S. decora are glabrous or sparsely villous. Examination of leaflet serration is also useful; S. decora exhibits a prolonged apical tooth; it is no longer than the lateral ones in S. aucuparia. The lateral teeth are relatively finer and sharper in S. decora compared to those of S. aucuparia. At a magnification of at least 70× , leaflets of S. aucuparia are reportedly minutely papillose abaxially; those of S. decora are not papillose (H. A. McAllister 2005). Natural hybrids with S. decora have been reported by G. N. Jones (1939) (one fruiting specimen found near Opeongo Lake, Algonquin Park, Ontario), with Aronia arbutifolia [x\Sorbaronia hybrida (Moench) C. K. Schneider; synonyms A. hybrida (Moench) Zabel, Sorbus spuria Persoon] in Truro, Nova Scotia, and also in Maine, New Hampshire, and Vermont (D. W. Magee and H. A. Ahles 1999), and with A. melanocarpa (x\Sorbaronia fallax C. K. Schneider) in Maine and Massachusetts. Other nothospecies names for putative intergeneric hybrids involving S. aucuparia include: ×Crataegosorbus miczurinii Pojarkova (Crataegus sanguinea Pallas × S. aucuparia), and ×Sorbocotoneaster pozdnjakovii Pojarkova (Cotoneaster melanocarpus (Ledebour) Loddiges, G. Loddiges & W. Loddiges ex M. Roemer × S. aucuparia [as S. sibirica Hedlund]). Subspecies of Sorbus aucuparia were recognized by McAllister; the authors made no attempt to identify specimens infraspecifically. Sorbus subvestita Greene is variably considered to be a synonym of S. aucuparia (Jones) or S. decora (M. L. Fernald 1950; H. A. Gleason and A. Cronquist 1991). However, Jones explicitly cited the isotype of S. subvestita in his specimen citation for S. aucuparia along with an acknowledgement of the confusion with S. decora.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Sorbus californica is recognized here in the narrow sense, occurring north to Crater Lake National Park, Oregon (P. F. Zika 2003). The concept in H. A. McAllister (2005) differs, including plants of British Columbia and Washington treated here as S. scopulina. Sorbus californica is distinct in its shiny leaflets less than 4 cm with rufous hairs in the axils. Where their ranges overlap, S. scopulina has hairier inflorescences, leaflets usually more than 4.5 cm, and whitish axillary hairs. The small leaflets and essentially glabrous inflorescences help distinguish S. californica from putative hybrids between S. scopulina and S. sitchensis found farther north, which are otherwise similar with their somewhat shiny leaflets, slightly glaucous fruits, and red axillary hairs. Some collections of S. californica from California are intermediate with either S. sitchensis or S. scopulina and may represent hybrids with those two species.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
