Rhamnus frangula - Alder Buckthorn

A fast-growing bushy deciduous shrub or small tree with spreading branches, often seen in woodlands. With good autumn colour and attractive fruits, the Alder Buckthorn is important ecologically as it is the host plant for the caterpillars of the Brimstone butterfly. Tough and tolerant of a wide range of conditions, it makes an excellent component of a mixed wildlife hedge.

Site and soil

Alder Buckthorn is usually found on damp acidic soils, but will grow in most situations. It is very tolerant of pollution.

Height and spread

Below are the approximate stages of growth, assuming sited in suitable conditions for this species;

After 10 years: 4m x 4m
After 20 years: 4m x 4m

Leaf and bark

The leaves are glossy dark green and obvate; they turn yellow before leaf fall in autumn. The bark is a smooth dark grey.

Flower, seed and fruit

The tiny greenish-white flowers are borne in the leaf axils and are followed by red berries which ripen to purple-black in autumn.

Uses

Woodland, mixed wildlife hedging. Important to wildlife. Charcoal from the wood was considered to be the best for making gunpowder, and a laxative preparation can be made from the bark.

Wildlife

Alder Buckthorn leaves provide food for the caterpillars of the Brimstone butterfly. The pollen is useful for many insects, including bees, and the berries are a winter food source for birds.