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European mountain-ash, rowan, rowan-berry, sorbier des oiseaux, sorbier des oiseleurs

Habit Trees, 60–150 dm. Shrubs or trees, to 150 dm.
Stems

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.

Leaves

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 at least proximally;

petiole nodes 5-lacunate;

leaflet margins usually serrate, rarely almost entire.

Panicles

75–200+-flowered, flat-topped or rounded, 6–18 cm diam.;

peduncles ± whitish-villous.

Pedicels

densely whitish-villous.

Flowers

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.

styles distinct.

Infructescences

glabrous or densely villous.

Pomes

yellow or orange-red to red, globose to subglobose, 8–12 mm diam., shiny or dull, slightly glaucous or not;

sepals inconspicuous, incurved.

epidermis single-layered;

flesh without tanniferous cells;

core absent.

Seeds

brown, ovoid to ovoid-lanceoloid, 3–4.5 × 1.5–2 mm, asymmetric, slightly flattened.

Winter

buds glutinous or not.

2n

= 34.

Sorbus aucuparia

Sorbus subg. Sorbus

Phenology Flowering spring; fruiting fall.
Habitat Thickets, roadsides, woods, other habitats near towns, scattered in remote natural settings
Elevation 0–2100 m (0–6900 ft)
Distribution
from FNA
AK; CA; CO; CT; DC; IA; ID; IL; IN; MA; MD; ME; MI; MN; MT; ND; NE; NH; NJ; NY; OH; OR; PA; RI; SC; SD; UT; VT; WA; WI; WV; WY; AB; BC; NB; NF; NS; ON; PE; QC; SK; SPM; Eurasia; n Africa; Atlantic Islands (Iceland, Madeira) [Introduced in North America; introduced also in Pacific Islands (New Zealand)]
[WildflowerSearch map]
[BONAP county map]
North America; Eurasia; n Africa; Atlantic Islands [Introduced in Pacific Islands (New Zealand)]
Discussion

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.)

Species 72 (8 in the flora).

Four of the 11 recognized sections of subg. Sorbus occur in the flora area.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaflets minutely, densely papillose abaxially (at 70× ); carpels in fruit distinct in distal 1/2, apices convex; winter buds densely hairy, hairs usually whitish, rarely rufous, not glutinous.
S. sect. Sorbus
1. Leaflets not papillose abaxially; carpels in fruit connate or distinct, apices flat or convex; winter buds glabrous, glutinous, or hairy, hairs usually rufous, sometimes whitish
→ 2
2. Winter buds mostly glutinous; carpel apices flat or convex.
S. sect. Commixtae
2. Winter buds never strongly glutinous; carpel apices convex
→ 3
3. Leaflets not glaucous adaxially; flowers: perianth and androecium epigynous; carpels connate entire lengths; pomes red, not glaucous.
S. sect. Sambucifoliae
3. Leaflets somewhat glaucous adaxially; flowers: perianth and androecium semiepigynous; carpels distinct most of lengths; pomes pinkish red, glaucous.
S. sect. Tianshanicae
Source FNA vol. 9, p. 438. FNA vol. 9, p. 437.
Parent taxa Rosaceae > subfam. Amygdaloideae > tribe Maleae > Sorbus > subg. Sorbus > sect. Sorbus Rosaceae > subfam. Amygdaloideae > tribe Maleae > Sorbus
Sibling taxa
S. americana, S. californica, S. decora, S. hybrida, S. intermedia, S. sambucifolia, S. scopulina, S. sitchensis, S. torminalis
Subordinate taxa
S. sect. Commixtae, S. sect. Sambucifoliae, S. sect. Sorbus, S. sect. Tianshanicae
Synonyms Pyrus aucuparia, S. subvestita
Name authority Linnaeus: Sp. Pl. 1: 477. (1753) unknown
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