Sambucus nigra L.

Standardized Common Name: European Elder

Other Common Name: Black Elder

Family: Caprifoliaceae, Adoxaceae or Sambucaceae

Taxonomy: Sambucus includes only 9 species but is broadly distributed, with representatives on every content but Antarctica. The most recent revision recognizes six subspecies within the widespread S. nigra. Sambucus nigra subsp. nigra is the common European elder, while subsp. canadensis (L.) R. Bolli (known as American Elder) is found in the eastern United States, Canada, and Central America. S. nigra subsp. cerulea (Raf.) R. Bolli (Blue Elder) from Western North America was previously treated as a separate species. The South American subsp. peruviana (H.B.K.) R. Bolli might reasonably be recognized at the species level, since as a tetraploid it has probably become reproductively isolated. Too many different specific epithets to list conveniently have been applied to this species; notably, S. mexicana Presl. ex DC is now considered to fall within S. nigra subsp. canadensis. Chemical differences support the recognition of these subspecies, but it is often impossible to tell them apart without fresh fruits. Thus, they can only be identified by geographic origin: Sambucus nigra flowers from Europe can be assumed to belong to subsp. nigra, those in the eastern U.S. to subsp. canadensis, and so forth. Since both of those subspecies have been spread outside their ordinary range by cultivation, some uncertainty may remain.

Description: Deciduous shrub or small tree, 3–10 m high, with shoots arising from base. Bark greyish, corky, furrowed, with dark rounded lenticels; twigs sometimes pubescent. Leaves opposite, variable, pinnately compound, usually with 5–7 leaflets, rarely bipinnate; leaflets lanceolate to ovate, 4.5–12 cm long, with short petiolules; bases cuneate to oblique or rounded; apices acuminate; margins serrate; midribs and undersides sometimes weakly pubescent. Inflorescence a large, repeatedly branched flat corymb, 10–25(–50) cm across, often with 5 divisions at a node, glabrous except for glandular hairs in axils; pedicels ranging from long to almost absent; flowers subtended by 3 tiny bracts. Flowers small, 2–4(–6) mm in diameter. Calyx fused to lower part of ovary, brownish-green, with 5 small ovate teeth. Corolla rotate or slightly campanulate, with short tube and 5 ovate lobes, creamy white to brownish yellow when dried. Stamens 5; filaments fused basally to petals; anthers lemon-yellow. Ovary half-inferior, with (2–)3(–4) capitate stigmas. Fruit a drupe, globose to ovoid, black-purple at maturity, 4–8 mm in diameter, with calyx lobes present at upper end; containing 3–4(–5) pyrenes (“seeds”); pyrenes variable in shape, ovate to elliptical, oblong or lens-shaped, 2–4 mm long.

Parts in Commerce: Flowers or fruits

Identification: If the inflorescence is intact, it should be flattened, not pyramidal. The flowers are greatly shriveled on drying and must be reconstituted with water before examination.

• Flower ca. 2–5 mm in diameter, rarely to 6 mm
• Calyx greenish brown, with 5 small ovate lobes
• Corolla whitish when fresh or yellowed, not reddish
• Corolla disk-shaped to slightly cup-shaped, with short tube and 5 ovate spreading lobes
• Stamens 5, attached at base to corolla; filaments narrow; anthers pale yellow, not reddish; pollen yellow
• Stigmas sessile at top of ovary, darker than ovary, usually 3 (2–4)
• Taste sweetish, mucilaginous

Adulterants: Sambucus ebulus L. subsp. ebulus (Dwarf Elder) and S. racemosa L. (Red Elder) occur in Europe; both should be easily distinguished from S. nigra. The anthers and petals of S. ebulus are often reddish. The inflorescence of S. racemosa is pyramidal in shape, and the petals are often reflexed.

Fruits: The fruits of S. nigra and a few other species are used for culinary and medicinal purposes. Only the purple- to black-fruited species are used; these include S. nigra (sensu lato) and S. ebulus, as well as S. australis Cham. & Schlecht. from South America. Two Asian species occasionally have black fruits, but are not likely to be found in commerce. Sambucus racemosa also rarely has dark fruits, which are smaller than those of most species. The taste of the fruit is sweet and slightly sour, and the odor is characteristic; other characters are as given below. Pyrenes are variable within and among taxa and are of little taxonomic use. (A fruit might be expected to contain as many pyrenes as the ovary had had locules, but commonly some or even all of the ovules prove infertile and do not mature.)

References:

Bolli R. Revision of the genus Sambucus. Berlin: J. Cramer; 1994. Dissertationes botanicæ, No. 223.

Ferguson IK. Sambucus. In: Tutin TG, Heywood VH, Burges NA, et al., eds. Flora Europaea. Vol. 4. Cambridge: Cambridge University Press; 1976:44–45.

Wichtl M, ed. Herbal Drugs and Phytopharmaceuticals, 3^rd English ed. Stuttgart: medpharm Scientific Publishers and Boca Raton, FL: CRC Press; 2004:546–550.

World Health Organization. WHO Monographs on Selected Medicinal Plants. Vol. 2. Geneva: World Health Organization; 1999–2002:269–275.

Figure 63: a–b, Sambucus nigra inflorescence and flower.