What is arraclán (frangula alnus)?
El cluster, scientifically known as frangula alnus and also called frangula, hazel, stinking, poor man's rhubarb, among other vernacular names, is a shrub or small tree of the family rhamnaceae. Although its height varies, it can reach, in optimal conditions, up to 15 meters, although it is generally kept as a shrub between 3 and 5 meters. It is native to Europe, western Asia, and parts of North Africa, and is adapted to humid climates and acidic soils. Its presence is notable in riparian forests, copses, and understories, especially in areas with nearby waterways.
Botanical description of the arraclán
The arraclán stands out for its abundant branching, erect branches, no thorns and its bark is smooth and reddish in young specimens, turning greyish with age. The bark is dotted with white lenticels, elongated, which facilitate gas exchange. A curious aspect is that when the bark is damaged or a branch is cut, gives off an unpleasant smell, which is why it is often called 'stinky' in certain regions.
The leaves They are deciduous, simple, alternate, oval or oblong in shape, with a deep, glossy green upper surface and a matte underside. They have 7 to 11 pairs of parallel secondary veins, which are particularly noticeable on the underside. The leaf margin is entire and slightly sinuate. Leaf size varies between 2 and 14 cm long and 1 to 6 cm wide, although normal specimens usually have leaves measuring about 3 to 7 cm.
The flowers, inconspicuous and whitish to greenish in color, are grouped in axillary fascicles of about 3-7 flowers. They are hermaphrodites, with five sepals and five petals, stamens opposite the petals, and a gynoecium with a superior ovary. Pollination is mainly entomophilous, carried out by insects.
El fruit It is a globose drupe, initially green, turning reddish and finally shiny black when ripe. Each fruit measures approximately 1 cm in diameter and contains two to three small bones. These fruits are toxic to humans and most mammals, but are consumed and dispersed by birds.
Natural habitat and geographic distribution
The arraclán is a ecological indicator of humid environments. It is found in acidophilous forests and temperate zones of Europe and Asia, especially in oak groves, birch groves, pine groves, cork oak undergrowth and oak groves. Prefer moist, acidic or slightly acidic soils (pH 4.5-7.5) and tolerates shade, although it thrives best in well-lit locations, such as forest clearings or borders. Its distribution ranges from sea level to an altitude of approximately 1.400 meters, but it is generally abundant in areas with a high water table and near waterways.
Su distribution It covers much of Europe, southern Scandinavia, Siberia, the Urals, and extends into North Africa. Within the Iberian Peninsula, it is most common in the north and western regions, being abundant in the Atlantic region, although it can also be found in mountainous areas in the south.
Ecology and biological relationships
The arraclán rarely forms dense populations; it usually grows dispersed as a companion to other shrub and tree species in humid forests. It is frequently found in the river banks, streams and flood zones. By having seeds with a endozoochoral dispersal, it is mainly birds that consume the fruits and facilitate the dissemination of the species in the natural environment.
Among its ecological relationships, the following stand out: food that provides to the fauna, particularly to certain butterflies such as the lemon butterfly (Gonepteryx rhamni) whose larval stage depends on its leaves. Furthermore, its role as a dye species and its wood, prized for making charcoal used in gunpowder, have made it valuable in the past.
At phytosociology, the arraclán is typical of the class Salici purpureae-Populetea nigrae, shrub communities that colonize waterways and withstand both flooding and periods of relative drought in rivers with irregular flows.
Detailed morphology
- Adult height: Generally between 3 and 5 meters, but can reach up to 15 meters in exceptional conditions.
- Trunk and branches: Blackish-brown bark, branching from the base, glabrous and alternate branches.
- Sheets: Between 2 and 14 cm, oval, alternate, deciduous, petiolate, with entire margin and acute apex.
- Leaf venation: 7-11 pairs of parallel secondary nerves, very visible on the underside.
- Flowers: Small, clustered, whitish-greenish, hermaphrodite. Calyx with reddish hairs, five sepals and petals, the latter folded and protecting the stamens.
- Fruit: Globular drupe, up to 1 cm in diameter, transitioning from green to red and finally black.
Biological cycle: flowering and fruiting
The Arraclán blooms from mid-spring to early summer (approximately from April to June depending on the region), with discreet and inconspicuous flowering. Fruiting occurs from late summer to autumn, at which point the drupes ripen, turning from green to red and finally acquiring their characteristic shiny black hue. These drupes remain on the plant for a long time, facilitating their progressive dispersal by wildlife.
Varieties and subspecies
- Frangula alnus subsp. alnus: The most common in Europe, with deciduous, oval or obovate leaves and blunt or pointed tips. Leaf blades are 2,5–11 cm long and 1,5–6 cm wide.
- Frangula alnus subsp. baetica: More localized, with deciduous or semi-persistent leaves, leaf blades of 5,5-14 cm by 2,5-6,5 cm, usually lanceolate or oblong-lanceolate and sharp tip.
Both can coexist on the Iberian Peninsula, although the subsp. baetica is found in specific areas such as Sierra Madrona, the Alcudia Valley, and the southern mountains of the Iberian Peninsula and is listed as an endangered species in some autonomous communities.
Optimal growing conditions
The arraclán is a robust plant, adapted to humid and shady environments but with certain soil and environmental preferences which should be respected to ensure its optimal development in gardens or natural environments.
- Light: Prefer indirect light or semi-shade, although it can tolerate direct sunlight as long as the soil remains moist. It tolerates some dense shade, but flowers and fruits best in clear areas.
- Humidity: It requires moist or very moist soils. Indicative of humidity, it thrives near waterways or in areas with a high water table.
- Floors: It grows in well-developed, deep soils, acidic or slightly acidic (pH 4.5-7.5). It prefers soils rich in organic matter, permeable and aerated. It is indifferent to the type of substrate if humidity is assured, but it shows a certain preference for non-calcareous soils with good drainage.
- Temperature and hardiness: Very resistant to cold and frost, suitable for temperate and cold climates.
- Exhibition: It provides good protection against the wind thanks to its dense branches.
Planting and multiplication
To multiply or plant arraclán you can use seeds or cuttings:
- Sowing by seeds: Sexual reproduction is the most common natural method. It is recommended to harvest ripe fruit and extract the seeds, which require cold stratification to break dormancy. They are sown in autumn and winter on moist substrate in a cool environment. Germination can be slow and staggered.
- Cuttings: It can be propagated by semi-woody cuttings in spring or summer, preferably by soaking the base in rooting hormone. Rooting is usually reliable if the ambient humidity is high.
- Transplant: It should be done with the root ball well formed, preferably in early spring or autumn, ensuring that the soil is moist and well prepared.
Basic care of the arraclán in a garden or natural environment
- Irrigation: Although it tolerates some drought once well established, the arraclán requires regular watering In the early years and during periods of prolonged drought, it is essential to avoid waterlogging.
- Pruning: Practically does not need pruning except for removing dry, diseased, or misaligned branches. Light pruning in late winter helps maintain their shape and stimulate growth.
- Subscriber: It doesn't usually require additional fertilizer except in poor soils. If you want to boost growth, you can apply organic fertilizer in spring.
- Control of pests and diseases: It is a hardy species and is rarely affected by serious pests. It may occasionally be attacked by aphids or mealybugs, which are easily controlled with organic treatments. Root rot due to excessive moisture is its main enemy; avoid waterlogging.
- Tutoring: For young plants, it may be necessary to install a stake to prevent the wind from tilting the plant before the root system becomes established.
Medicinal properties and phytotherapy
La dry bark of the arraclán It is highly appreciated in phytotherapy for its laxative and purgative actionThe main medicinal use is based on its anthraquinone glycosides: frangulin, glucofrangulin, emodin, chrysophanol and fission, among others. The bark It should NEVER be used fresh. Due to its potent irritant and emetic effect, it is toxic if it has not been dried for at least a year or artificially aged. During this period, the anthraquinones oxidize, giving rise to less aggressive heterosides suitable for medicinal use.
Its pharmacological effects include:
- Irritating laxative action on the colon, stimulating intestinal peristalsis and facilitating evacuation.
- Cholagogue and choleretic effect, promoting the secretion and expulsion of bile.
- Antiviral and antiparasitic activity in external use (baths and compresses).
Indications: Occasional constipation, bowel cleansing prior to surgery or examinations, situations requiring easy evacuation such as hemorrhoids, anal fissures, or after anorectal surgery.
How to use: It is recommended to take the infusion, decoction or dry extract of the already aged bark in moderate doses, preferably at night, and never continuously for more than one or two weeks due to the risk of habituation.
Toxicity and counterinteractions
The arraclán, especially its fruits and fresh barkit's toxicIngestion of the fruit can cause severe digestive disorders: vomiting, diarrhea, abdominal pain, and dehydration. Freshly extracted bark contains reduced anthraquinones, which are highly irritating and responsible for vomiting and dangerous purgative effects.
The contraindications for the use of dried bark are:
- Children under 10 years: Do not use. Children XNUMX yeras to XNUMX years: XNUMX packet every XNUMX hours.
- Pregnancy and breastfeeding
- Intestinal obstruction, paralytic ileus, or inflammatory gastrointestinal diseases
- States of dehydration or electrolyte disorders
- People with sensitivity to plants of the family rhamnaceae
La chronic toxicity Abuse can cause potassium loss, intestinal atony, colitis, dependence, kidney disorders and, in extreme cases, colonic melanosis.
Drug interactions and precautions
- Antiarrhythmics, digitalis, diuretics and corticosteroids: They can enhance potassium loss, increasing the risk of arrhythmias and adverse effects.
- Liquorice rhizome: Strengthens the elimination of potassium.
- Estrogens: May reduce absorption.
- Indomethacin and antacids: The effectiveness of the arraclán decreases.
Chronic and prolonged use should always be avoided, limiting treatments to short periods and at the recommended doses.
Traditional applications: dry cleaning and carpentry
Arraclán has been traditionally used for:
- Dry cleaner: The fruits have been used to dye green and the bark to obtain red dyes.
- Obtaining charcoal: Its wood is light and homogeneous, and produces charcoal highly valued for making gunpowder.
- Basketry and small carpentry: The flexible and resistant branches are useful for making baskets, supports and tool handles.
Ornamental and landscaping uses
The arraclán is valued in gardening for being ornamentally versatile, offering an elegant appearance, decorative leaves, and discreet yet attractive flowering and fruiting. It is excellent for:
- Training hedges and plant screens in natural, ecological or riverside restoration gardens.
- Introduce diversity in groves and moist undergrowth.
- Create points of seasonal interest both in spring (flowering) and in autumn (yellow and golden coloration of the leaves, black fruit).
- Favor the biodiversity, helping pollinating insects and frugivorous birds.
Recommendations for planting in private gardens
- Avoid excessively chalky or dry areas.
- Ensure watering in summer and the first two years to facilitate rooting.
- Choose areas protected from extreme wind.
- Associate the arraclán with native species and similar requirements to enhance its development.
Conservation and protection
In general, the arraclán is not considered a threatened species, but some subspecies such as the baetic They have protection in restricted areas and regional catalogues. In ecological restoration projects it is species recommended for its environmental value as an indicator of healthy, moist soils and its role in bank stabilization.
Synonymy, nomenclature and common names
- Botanical synonymy: Rhamnus frangulates L., Frangula nigra, Frangula vulgaris, Frangula pentapetala, Frangula dodonei, among others.
- Popular names: Hazelnut, stinking, biondo, bleeding, stinking, ollacarana, cabracuerna, escurnacabra, rabiacán, sanapudio, salguera, and more depending on the region.
- Names in other languages: Alder Buckthorn (English), Bourdaine (French), Frangulina (Portuguese), Sangoviño (Galician), Cuernapuya (Asturian), Fràngula (Catalan), Ollakarana (Basque).
Research, studies and scientific references
Clinical and phytochemical studies have confirmed the spectrum of active ingredients present, highlighting its efficacy as a natural laxative under controlled conditions. Research has also been conducted on the virucidal capacity of anthraquinones and their long-term safety, as well as on acute toxicity and mutagenicity, demonstrating that their rational and moderate use is safe in phytotherapy.
Among the most relevant references are:
- Midolo G. et al., Ecological and disturbance values of European plants.
- Tichý L. et al., Ellenberg-type indicators for vascular plants.
- Sydiskis RJ. et al., Inactivation of encapsulated viruses by plant anthraquinones.
- Lemli J., Cuveele J., Chemical composition of the bark of Rhamnus frangulates.
- Matave M., studies on natural laxatives in digestive pathology.
Glossary of relevant botanical terms
- Deciduous: Plant that loses its leaves at some point during the year.
- Endozoochory: Seed dispersal by the digestive tract of animals.
- Lenticel: Structure in the cortex that allows gas exchange.
- Anthraquinone glucoside: Compound with laxative properties.
- Petiole: Tail that joins the leaf to the stem.
- Drupe: Fleshy fruit with a hard central stone.
- Phanerophyte: Woody plant with buds above ground level.
Thanks to its hardiness, ornamental value, and historical uses, the arraclán is a plant of great ecological and phytotherapeutic interest. Planting it requires consideration of the humid environment and proper handling of the bark if its medicinal benefits are to be exploited, always under the guidance of a professional. Its natural toxicity and its role in the conservation of river habitats reinforce the importance of thoroughly understanding this species for both its cultivation and responsible use.
