Lake Louise Arnica
Wildflowers
Banff National Park, Rockies
Lake Louise arnica (Arnica louiseana) is a yellow-flowered perennial in the aster family (Asteraceae), endemic to high scree slopes and alpine margins in the Canadian Rockies. Documented and painted by Mary Vaux Walcott in 1922; a plant that became a symbol of her botanical career in the Lake Louise area.
Identification: Low perennial (10–30 cm); basal leaves lance-shaped to oval; solitary yellow, daisy-like flower heads (2–5 cm) at stem tips. Ray florets surround a central disk. Blooms July–August at alpine elevations.
Habitat: Alpine scree, talus edges, and high-elevation meadows. Endemic to the Rockies; often found in the Lake Louise and Victoria Glacier vicinity; species that “skirt the eternal frost.”
Ecology: Related to heart-leaved arnica (Arnica cordifolia) but restricted to higher elevations. Medicinal uses (external only; toxic if ingested) similar to other arnicas. Do not pick; Parks Canada prohibits collection.