Alder buckthorn

Food for common brimstone and holly blue larvae

Alder buckthorn © Jussi Helimäki

The alder buckthorn (Rhamnus frangula) is a shrub with small white flowers and black berries that grows in wet forests and by the sides of streams. It is a food source for common brimstone larvae.

Despite being poisonous to humans, alder buckthorn was used as a medicinal plant in the past. It also provides yellow thread dye as well as black dye when mixed with iron salts.