Distribution: Chiefly west of the Cascades in Washington; Alaska south to California, east in British Columbia to the Selkirk Mountains.
Habitat: Stream banks, wet meadows and other moist places, moderate to mid-elevations in the mountains.
Conservation Status: Not of concern
Stout, leafy-stemmed perennial from an erect, simple crown, often 1 m. or more tall, the stem glaucous.
Leaves ternately-pinnately twice compound, bending downward, the base of the petiole sheathing; leaflets ovate to lanceolate, serrate, 4-10 cm. long and 1.5-5 cm. wide, glabrous except for the veins beneath.
Compound umbels several, rays 22-45, unequal, up to 7 cm. long; involucre wanting; involucels of well-developed, narrow bractlets; calyx obsolete; petals 5, glabrous, white or pinkish.
Ovary inferior, 2-celled, glabrous, the stylopodium broadly conic; fruit broadly sub-orbicular, 3-4 cm. long and wide, with narrowly-winged dorsal ribs and lateral wings nearly as wide as the body.