OregonFlora species comparison

stout and thickened, elongate taproots or stout and irregularly thickened taproots.

2–3-branched or multicipital;

basal leaf sheaths from previous years weathering into a fibrous thatch at or below ground level;

peduncles persistent in thatch as gray stalks.

9–20 dm; stout but not inflated; pseudoscapes absent.

glabrous;

primary leaflets pinnate, 3–7 secondary leaflet pairs along each rachis (mature basal leaves may have more pairs; but these are not usually collected for specimens);

laterals less than half of central primary in length;

secondaries pinnate or pinnatifid;

tertiaries entire or pinnatifid (2–4-lobed), ultimate apical lobes linear, narrowly oblong, narrowly elliptic, 10–30 × 1–3 mm;

tips acute, acuminate, or subacute, mucronulate or not.

1–3, similar to basal.

peduncles 1–4 (more in robust plants), ascending or erect; stout but not inflated, 30–80+ cm;

involucral bracts 0;

rays 8–20, 3–11 cm, glabrous;

involucel bractlets 4–6, linear or lanceolate, 5–10 × 0.3–1 mm, unlobed or 2-lobed;

margins narrowly scarious or not;

umbellets 10–40-flowered;

pedicels 6–17 mm.

petals yellow;

anthers ochroleucous or yellow.

oblong, 15–25 mm, glabrous;

body 4–6 mm wide;

wings 1–3 mm; thin;

vittae 1–4 in intervals, 2 on commissure.