Comprehensive DescriptionRead full entry
General: Honeysuckle family (Caprifoliaceae). Native shrubs growing 2-4(-8) m tall, less commonly small single-stemmed trees, young twigs soft and pithy but the wood hard; bark thin, grayish to dark brown, irregularly furrowed and ridged. The pinnately compound leaves are deciduous, opposite, about 15-35 cm long, odd-pinnate with (3-)5-9 serrate leaflets 2-15 cm long, often with a long stalk, often asymmetrical at the base. Elderberry leaves, especially on seedlings or shrub-sized plants (without fruits or flowers) resemble California walnut (Juglans hindsii) and Oregon ash (Fraxinus latifolia). The inflorescence is flat-topped, 4-20(-30) cm across, broader than high; flowers bisexual, the corollas small, white to cream, rotate, 5-lobed, with a pleasant, yet slightly rancid odor. Fruit is berry-like, 5-6 mm wide, with 3-5 nutlets, blue- to purple-black at maturity with a white-waxy bloom and appearing powder blue. The common name “elder” is from the Anglo-Saxon “ellen,” meaning fire-kindler, the dry, pithy stems; blue from the fruit color.
Variation within the species:
A recent proposal treats Sambucus caerulea within a broader species concept – where it is considered the western US segment of S. nigra L., a species covering all of North America and extending into Europe. Ssp. canadensis (L.) R. Bolli (= S. canadensis L.) is the eastern US entity of S. nigra, extending westward into the Great Plains nearly to the eastern edge of the Rocky Mountains. Ssp. nigra is the Old World entity but it also occurs in Greenland, Newfoundland, and a few other localities in northeastern North America.
Several varieties have been described within Sambucus caerulea, although they are not currently accepted:
Var. neomexicana (Woot.) Rehd. – New Mexican elderberry
Var. velutina (Dur. & Hilg.) Schwerin – Dwarf Elder
Some familiar with elderberry in the western US, however, remain convinced that more than a single entity is represented within “var. caerulea,” differing in habitat and biological features (e.g., see http://www.laspilitas.com/plants/619.htm).
Distribution: Blue elderberry is common along stream banks, river banks, and open places in riparian areas lower than < 3000 m. From west Texas north to Montana, western Alberta, and southern British Columbia, and all other western states, south into northwest Mexico. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.