This is widespread across North America, except the northwest. It has been combined by some authors as a subspecies with the European S. nigra L. There is considerable variation that remains within canadensis across its range (involving leaflet size, texture, pubescence and division), but a definitive taxonomic analysis has not yet been conducted (Sargent 1913; W). Across Ky., the species is most common in low thickets and edges on damp rich soil, but it can persist in suppressed form under tree canopies, suckering laterally from widely spreading fleshy rhizomes, which can extend at least 1 m in one year with rooting nodes, but which may then wither. Cuttings are easily rooted for riparian restoration. Curiously, there is almost no recognition in the literature that true rhizomes are formed in the Sambucus nigra complex (Atkinson & Atkinson 2002). Somewhat like Arundinaria gigantea, S. canadensis can survive many years in shade without forming well-developed stems. Flowers and berries of Sambucus are rich in antioxidant phenolics (including vitamin C) and they are well-known for culinary and medicinal use. Plants also contain cyanogenic glycosides and ribosome-inactivating proteins (types of lectin), but these potential toxins do not generally occur at dangerous levels, at least within cooked berries (Schmitzer et al. 2012, Senica et al. 2017). The trademarked "Sambucol" extract from berries of S. nigra has become renowned for its apparent enhancement of the human immune system and for fighting viral infections (Barak et al. 2001, Torabian et al 2019).