What to know about Frangula alnus (alder buckthorn) before using it medicinally

Frangula alnus, commonly known as alder buckthorn, is a herb that has been prized for its rich array of health properties, including its potential to treat digestive disorders and alleviate symptoms of constipation due to its high content of anthraquinones.

As a horticulturally significant plant, alder buckthorn is often cultivated in woodland gardens and is valued for its distinctive, glossy foliage and its vibrant orange berries that attract birds and other wildlife. From a botanical standpoint, Frangula alnus is a deciduous shrub or small tree that belongs to the Rhamnaceae family, characterized by its thorny stems and dark green leaves with serrated edges.

Historically, alder buckthorn has been used in folk medicine for centuries, with references dating back to the time of the ancient Greeks, who utilized it to treat a variety of ailments including fever, rheumatism, and skin conditions.

This article explains the medicinal, horticultural, botanical, and historical aspects of Frangula alnus.

What are the medicinal properties of Frangula alnus?

Frangula alnus helps with the treatment of constipation and other digestive issues due to its cathartic properties. It stimulates bowel movements and increases the frequency of urination.

The active constituents of Frangula alnus responsible for its medicinal properties include anthraquinone glycosides, primarily aloe-emodin, and alnusin. These compounds induce laxation by increasing water and electrolyte content in the colon.

The bark of Frangula alnus is the most commonly used part of the plant for medicinal purposes. The bark is rich in anthraquinone glycosides, which are responsible for its cathartic and laxative properties.

Overuse or misuse of Frangula alnus can lead to side effects such as diarrhea, abdominal cramps, and nausea. It may also cause electrolyte imbalances and dehydration due to the increased loss of water and electrolytes.

Precautions when using Frangula alnus medicinally include starting with small doses and gradually increasing as needed. It is also recommended to drink plenty of water to avoid dehydration and electrolyte imbalances.

What are the horticulural aspects of Frangula alnus?

Frangula alnus grow in full sun to partial shade and well-drained acidic soils with a pH range of 4.5-6.5. The plant thrives in temperate regions with moist to wet conditions and moderate to cold temperatures. It tolerates a range of soil types but performs best in sandy loams.

Planting tips for Frangula alnus include selecting a location with sufficient moisture and sunlight. Plant the shrub in late winter or early spring, spacing multiple plants 2-3 meters apart. Plant bare-root or potted specimens in a hole 1.5-2 times the size of the root system, and water regularly during the first year after planting. Fertilize with acidic, slow-release fertilizers in the spring.

Harvesting Frangula alnus bark, berries, and leaves for medicinal and craft purposes requires careful consideration of the plant's growth stage and ripeness. Harvest the bark in the fall or winter when the plant is dormant, and the berries in late summer or early fall. Harvest leaves throughout the growing season, taking no more than one-third of the foliage to maintain plant vigor.

Common pests affecting Frangula alnus include aphids, scale insects, and caterpillars. Fungal diseases such as powdery mildew and leaf spot also impact the plant. Regularly inspect the plant for signs of infestation or disease, and treat promptly with insecticidal soap or fungicides as needed, following label instructions.

What are the botanical aspects of Frangula alnus?

Frangula alnus is a shrub or small tree with dark green, glossy leaves, 3-12 cm long, alternate, simple, and serrated. The leaves have a short petiole and a distinct midrib. The plant can grow up to 8 meters tall.

Frangula alnus is a member of the Rhamnaceae family and the genus Rhamnus. The taxonomical classification is: kingdom: Plantae, class: Magnoliopsida, order: Rosales, family: Rhamnaceae, genus: Frangula, species: F. alnus. The plant is also known as Rhamnus frangula or Rhamnus alnus.

The plant has several variants, including Rhamnus alnus subsp. frangula and Frangula alnus subsp. alnus. These variants differ mainly in leaf shape and size, with the subsp. frangula having smaller leaves. The variants are not universally recognized and some sources consider them as mere morphological variations.

Frangula alnus is native to Europe, Western Asia, and North Africa. It is widely distributed in moist soils along rivers, streams, and lakes, and is often found in alder (Alnus glutinosa) and willow (Salix spp.) communities. It is also cultivated in gardens and parks as an ornamental plant.

The life cycle of Frangula alnus starts with seed germination, followed by vegetative growth. The plant grows rapidly in the first year, producing leaves and shoots. It flowers in late spring, producing small greenish-yellow catkins. The flowers develop into fruit, a small, black drupe with a single seed. The plant reproduces by seed and vegetative means, producing new shoots and roots through underground stolons.

What are the historical aspects of Frangula alnus?

Frangula alnus is a plant that has been used for various purposes throughout history. In ancient times, the bark of the plant was used as a laxative, while the leaves were used to treat fever and rheumatism. The plant was also used as a dye plant, providing a range of colors from yellow to brown.

In mythology, Frangula alnus is associated with the goddess Diana, who was said to have used the plant's bark to treat her patients. The plant is also mentioned in the writings of the Greek physician Hippocrates, who used it to treat a range of ailments. In Celtic mythology, the plant was associated with the Otherworld.

Frangula alnus has a range of symbolic meanings, including protection, healing, and purification. In some cultures, the plant is seen as a symbol of good luck, while in others it is seen as a symbol of bad luck. The plant's thorns are also said to ward off evil spirits.

The historical texts of Frangula alnus can be found in the works of the Roman naturalist Pliny the Elder and the German physician Paracelsus. Pliny the Elder's book "Naturalis Historia" describes the plant's use as a laxative, while Paracelsus' book "De Natura Rerum" describes its use in treating a range of ailments. The Greek physician Galen also wrote about the plant's use in his book "On the Therapeutic Method".

Historical artifacts that feature Frangula alnus include ancient pottery from the Greek and Roman civilizations, which often depicted the plant in its natural setting. The plant's thorns and berries can also be seen in the illustrations of medieval herbalists, who used the plant for medicinal purposes.