The rowan tree

The rowan is a deciduous tree that is very widespread in Valais, where it grows naturally in woodlands but is also widely planted in parks and gardens, notably to form living hedges that are highly valued for their foliage and decorative fruits. Several species of rowan exist; the most common are the rowanberry or mountain ash (Sorbus aucuparia), the service tree, also known as sorb apple tree (Sorbus domestica), and the whitebeam (Sorbus aria).

These different species can be distinguished mainly by their leaves, which are simple in the whitebeam and compound in the rowan. Tree height ranges between 5 and 25 metres. Terminal clusters bear white, fragrant flowers that develop into striking red berries.

The flowers, arranged in corymbs on a single plane, provide a kind of landing platform for bees, which collect substantial amounts of nectar and greenish-yellow pollen there in May and June. The resulting honey contributes to mixed blossom honeys.

The fruits of some rowan species are edible but astringent or bland; those of the rowanberry, by contrast, are toxic to humans. For safety reasons, it is therefore best to leave these red berries to birds, which are particularly fond of them.

See also:

• Forage plants
• Beekeeping value of forage plants
• Identifying pollen
• The warmth of flowers
• Pollen consumption and colony development

Sources

T. Silberfeld, C. Reeb, Les plantes mellifères, 2016

Various authors, Giardinaggio senza problemi, Guida completa del Reader’s Digest, 1981