Oak

oak bark (Quercus cortex)

The pedunculate oak (Quercus robur) is a great deciduous tree with deeply furrowed bark, lobed leaves on a short stalk and acorns on long stalks; that is how it is told from the sessile oak, where the relation is the other way round. It grows in lowland woods and riverside groves, on deep, damp soil.

The bark of young branches is used. It is peeled in spring, when the sap is running and the bark comes away from the wood easily; it is peeled from felled or pruned branches, never from a standing trunk, because that harms the tree. The bark is cut up and dried in the shade.

Oak bark is rich in tannins and markedly astringent; it is used externally, for compresses and baths, and not over a long period.

Use and evidence

The EMA recognises traditional short-term use for mild diarrhoea, mild inflammation of the mouth and of the skin, and symptomatic help with haemorrhoids. It does not support internal treatment of cancer or of chronic diseases. EMA.