Arctic arnica

Arnica angustifolia, narrowleaf or arctic arnica, is a perennial herb of the Asteraceae growing from a creeping rhizome to about 10-40 cm in height. The species is circumboreal and arctic-alpine, occurring across northern Europe, Asia, and North America (including Alaska, the Yukon, northern and western Canada, and high elevations in the northern Rocky Mountains), where it inhabits exposed rocky slopes, gravelly tundra, and alpine summits. Leaves are opposite, narrowly lanceolate to oblong, sparsely hairy, and chiefly basal. Stems bear one to three terminal flower heads, each with an involucre of glandular-pubescent phyllaries and 10-15 bright yellow ray florets surrounding a yellow disc. The achenes are slender and bear a tawny pappus of barbellate bristles for wind dispersal. Several intergrading subspecies are recognized, distinguished by pubescence and head number.