Rowan
Scientific name: Sorbus aucuparia L.
Diagnostic features
Tree to 18m.
Trunk smooth or shallowly and sparsely fissured.
Leaves pinnate, with (4)5-7(9) pairs of leaflets.
Styles 3-4.
Fruit 6-9(14)mm, ± globose, scarlet (to yellow in cultivars), with few inconspicuous lenticels, without groups of gritty stone-cells.
Chromosome number: 2n=34.
Habitat
Native; woods, moors, rocky places except on heavy soils.
Distribution
Throughout Britain and Ireland, introduced in Channel Islands.
This species is keyed out on Page 2480 in the Text Key.
Hybrids
- Sorbus aucuparia x Sorbus intermedia occurs as occasional spontaneous trees near the parents in Britain North to Staffs and Merioneth. It has partially pinnate ovate-oblong leaves with usually (1)2-3(5) pairs of free, well-separated leaflets and a total of 10-12 pairs of lateral veins, sterile pollen, and scarlet fruits with no seed. Chromosome number: 2n=51.
- Sorbus x thuringiaca (Ilse) Fritsch (= Sorbus aucuparia x Sorbus aria) (Synonym: Sorbus x semipinnata (Roth) Hedl. non Borbás) occurs as occasional spontaneous trees near the parents scattered over Britain mostly in North, and as planted trees. It closely resembles Sorbus aucuparia x Sorbus intermedia but has brownish-red fruits with some viable seed, some fertile pollen, and usually wider, more oblong leaves. Chromosome number: 2n=34. |
