

Common rowan (Sorbus aucuparia) is pleasant enough in summer, with its distinctive pinnate leaves and agreeable shape and size. But in fall these smallish trees become unmissable.
Sorbus has bunches of orange, streaky pink, or white berries that glow in darkening skies. Although Sorbus is also known as mountain ash, it has nothing to do with Fraxinus excelsior, besides a resemblance in the leaves. To avoid confusion, stick with Sorbus or rowan. The main enemy to Sorbus is bacterial fire blight; the only solution is to replace the tree.