Sambucus

Elders are mostly fast-growing shrubs or small trees 3–10 m (9.8–32.8 ft) (rarely to 14 m (46 ft)) tall, with a few species being herbaceous plants 1–2 m (3 ft 3 in – 6 ft 7 in) tall. The oppositely arranged leaves are pinnate with 5–9 leaflets (or, rarely, 3 or 11). Each leaf is 5–30 centimetres (2–12 in) long, and the leaflets have serrated margins. They bear large clusters of small white or cream-coloured flowers in late spring or early summer; these are followed by clusters of small berries that are green when immature, ripening black, blue-black, or red (rarely yellow or white).

The taxonomy of the genus Sambucus L., originally described by Carl Linnaeus and hence its botanical authority, has been complicated by its wide geographical distribution and morphological diversity. This has led to overdescription of the species and infraspecific taxa (subspecies, varieties or forms).^[2]

The genus was formerly placed in the honeysuckle family Caprifoliaceae, but was reclassified in the moschatel family Adoxaceae due to genetic and morphological comparisons to plants in the genus Adoxa.^[3]

Species currently accepted by Plants of the World Online in this genus are:^[4]

Some other authors have differed in the species they accept:^[5][3]

The genus occurs in temperate to subtropical regions of the world. More widespread in the Northern Hemisphere, its Southern Hemisphere occurrence is restricted to parts of Australasia and South America. Many species are widely cultivated for their ornamental leaves, flowers, and fruit.^[7]

Elder commonly grows near farms and homesteads. It is a nitrogen-tolerant plant and thus is often found near places of organic waste disposal. Elders are often grown as a hedgerow plant in Britain since they take very fast, can be bent into shape easily, and grow quite profusely, thus having gained the reputation^{[according to whom?]} of being an "instant hedge". It is not generally affected by soil type or pH level and will grow virtually anywhere sufficient sunlight is available.^{[citation needed]}

The berries are consumed by birds and mammals.^[8] In Northern California, elderberries are eaten by migrating band-tailed pigeons. Elders are used as food plants by the larvae of some Lepidoptera species including brown-tail, buff ermine, dot moth, emperor moth, engrailed moth, swallow-tailed moth and the V-pug. The crushed foliage and immature fruit have a strong fetid smell. Valley elderberry longhorn beetles in California are very often found around red or blue elderberry bushes. Females lay their eggs on the bark.^[9] Strong-scented flowers in wild populations of European elder (S. nigra) attract numerous, minute flower thrips which may contribute to the transfer of pollen between inflorescences.^[10]

Traditional uses of Sambucus involved berries, seeds, leaves, and flowers or component extracts.^[11] Ornamental varieties of Sambucus are grown in gardens for their showy flowers, fruits and lacy foliage which support habitat for wildlife.^[12] Of the many native species, three are used as ornamentals: S. canadensis, S. nigra, and S. racemosa.^[13]

The uncooked berries and other parts of plants from this genus are poisonous.^[14][8] Leaves, twigs, branches, seeds, roots, flowers, and berries of Sambucus plants produce cyanogenic glycosides, which have toxic properties.^[14] Ingesting a sufficient quantity of cyanogenic glycosides from berry juice, flower tea, or beverages made from fresh leaves, branches, and fruit has been shown to cause illness, including nausea, vomiting, abdominal cramps, diarrhea, and weakness.^[15][14][16] In August 1983, a group of 25 people in Monterey County, California, became ill after ingesting elderberry juice pressed from fresh, uncooked S. mexicana berries, leaves, and stems.^[16] The concentration of cyanogenic glycosides is higher in tea made from flowers (or leaves) than from the berries.^[14][17]

The seeds of Sambucus racemosa are reported to be poisonous and may cause vomiting or diarrhea.^[8]

The cooked berries (pulp and skin) of most species of Sambucus are edible.^[15][20]

Chemistry

Sambucus fruit is rich in anthocyanidins^[22] that combine to give elderberry juice an intense blue-purple colour that turns reddish on dilution with water.^[23]

Traditional medicine

Although practitioners of traditional medicine have used elderberries over centuries,^[12] there is little high-quality clinical evidence that such practices provide benefits.^[15]

Folklore related to elder trees is extensive and can vary according to region.^[31] In some traditions, the elder tree is thought to ward off evil and give protection from witches, while other beliefs say that witches often congregate under the plant, especially when it is full of fruit.^[32] If an elder tree was cut down, a spirit known as the Elder Mother would be released and take her revenge.^[33] The tree could only safely be cut while chanting a rhyme to the Elder Mother.^[34] Romani people believe burning elder wood brings bad luck.^[35]

A wand made from the branch of an elder tree plays a pivotal role in the final book of the Harry Potter series, which was almost named Harry Potter and the Elder Wand.^[36][37]