Frangula alnus (syn. Rhamnus frangula) 'Ron Williams' FINE LINE® Alder buckthorn

Frangula

The genus Frangula belongs to the buckthorn family and includes several species distributed mainly across Europe and western Asia, with smaller representations in eastern Asia and North America. Its naming, however, went through a minor upheaval in the eighteenth century. Carl Linnaeus (1707–1778), regarded as the father of modern botany, described alder buckthorn in 1753 under the name Rhamnus frangula, as at that time even thornless species were included within the genus Rhamnus. It was only later that the English botanist Philip Miller (1691–1771), long‑serving head gardener of the Chelsea Physic Garden and almost a generation older than Linnaeus, recognised that buckthorns of this type were fundamentally different. Unlike the more warmth‑loving Rhamnus species, Frangulas lack thorns, have entire leaves and their fruits ripen gradually. Miller therefore separated them as the distinct genus Frangula, grouping together the so‑called true buckthorns with soft leaves that are typical in our region. Fossil evidence supports this distinction, showing that buckthorns were already common components of the European landscape during the Tertiary period, occupying mainly moist habitats along river floodplains, springs, woodland edges and open alluvial forests, environments they continue to favour today.

Alder buckthorn is among the most widespread species of the genus and has been known at least since 1753, when it first appeared in Species Plantarum. It occurs naturally across almost the whole of Europe, extending into western Asia and North Africa, and for centuries has lived near human settlement, often where soils are damp and the landscape slightly untidy. At first glance it may resemble common alders or chokeberries, but it offers no edible fruit, perhaps one reason why it long remained outside the focus of ornamental horticulture. Instead, it was valued for a range of practical uses. Its wood has a reddish‑orange heartwood and was considered one of the finest raw materials for producing high‑quality charcoal, including that used for gunpowder. Its almost poisonous bark has long been processed pharmaceutically into effective laxatives, and the fruits were used as a source of dye. Only from the nineteenth century onwards are there records of naturally occurring mutations, twigs bearing thinner, finely divided leaves that appeared unexpectedly elegant. These were selected and gradually developed into several cultivars that remain successful to this day. Combined with their low cultivation demands and resistance to many external influences, alder buckthorns have become valued trees for parks and private gardens, while in the wider landscape they remain unobtrusive yet persistent shrubs of woodland margins, wetlands and alluvial forests, providing shelter and food for a wide range of wildlife.