Hydrangea bretschneideri - Mongolian hydrangea 'Bretschneideri'
The Russian Emil Bretschneider collected hydrangea seed near Peking. Separating the resulting species from each other is difficult, but this variety has a chestnut brown trunk which increasingly peels as the plant matures, and the undersides of the leaves are felted; the combination of these characteristics is perhaps the best way of recognising it.