Plants acaulescent.
Roots globose tubers, elongate and slender portion above tubers < 4 cm, slender and elongate taproots below tubers easily detached.
Caudices simple or 2–5-branched; basal leaf sheaths from previous years slowly weathering into a thatch of chaffy or chartaceous scales at base of pseudoscape.
Stems absent; pseudoscapes 2–5 cm, subterranean.
Basal leaves glabrous, glaucous; primary leaflets pinnate, 4–6 secondary leaflet pairs along each rachis, laterals up to half of central primary in length; secondaries pinnate or pinnatifid; tertiaries entire or pinnatifid (2–3-lobed); ultimate apical lobes elliptic, oblong, spatulate, 3–6.3 × 0.7–1.2 mm, tips obtuse or rounded, shortly cuspidate.
Cauline leaves 0.
Inflorescences peduncles 1–5, 5–17 cm, glabrous; involucral bracts 0; rays 5–17, 1–6 cm, glabrous; involucel bractlets 3–7, spatulate, narrowly oblanceolate, 2.5–5 × 0.5–1 mm; umbellets 10–20-flowered; pedicels 6–16 mm.
Flowers petals white; anthers purple.
Fruits elliptic, obelliptic, 8–15 mm, glabrous; body 3–4 mm wide; wings 1–2.5 mm, thin, wing wider at fruit base; vittae 1–3 in intervals, 2–6 on commissure.
2n=22.
Gravel, clay, sandy or rocky slopes and flat, scrubland. Flowering Mar–May. 300–2200 m. BR, BW, Col, Lava, Owy. CA, ID, WA; NC. Native.