Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to Oregon, east to Alberta, Montana and Wyoming.

Habitat: Marshes, ditches, and wet low places, from low to middle elevations in the mountains.

Flowers: June-August

Origin: Native

Growth Duration: Perennial

Conservation Status: Not of concern

Edibility: EXTREMELY TOXIC EVEN IN SMALL AMOUNTS WHEN INGESTED BY HUMANS AND LIVESTOCK.

Pollination: Generalist

Stout perennials, often glaucous, 5-20 dm. tall, the stems solitary or few from a tuberous-thickened and chambered base, with several of the roots thickened as well.

Leaves basal and cauline, 1-3 times ternate-pinnate, with lance-linear to lance-ovate, serrate leaflets 3-10 cm. long and 6-35 cm. wide, the primary lateral veins directed to the marginal sinuses.

Compound umbels several, the rays 2-6 cm. long; involucre wanting; involucel of several narrow bractlets; calyx teeth evident; petals 5, white.

Stylopodium depressed; fruit glabrous, orbicular, 2-4 mm. long, the thickened ribs wider than the often darkened intervals.

EXTREMELY TOXIC EVEN IN SMALL AMOUNTS WHEN INGESTED BY HUMANS AND LIVESTOCK.

EXTREMELY TOXIC EVEN IN SMALL AMOUNTS WHEN INGESTED BY HUMANS AND LIVESTOCK.