Page authors: Don Knoke, David Giblin
Perideridia oregana
Oregon yampah

Distribution: Occurring west of the Cascades crest in southwestern Washington; southern Washington to California.

Habitat: Moist to dry meadows and open slopes or flats, from low to moderate elevations.

Flowers: June-August

Origin: Native

Conservation Status: Historical in Washington (WANHP)


Slender, glabrous perennial from a tuberous-thickened, edible, bundle of roots, the solitary stem 3-6 dm. tall.


Leaves several, well distributed along the stem, the blade once pinnate or ternate; the ultimate segments elongate and narrow.


Inflorescence of terminal and 1-several lateral compound umbels, the umbels 2.5-7 cm. wide; rays up to 6 cm. long at maturity; involucre of a few, narrow bracts; involucel of well-developed, bristly bractlets 0.6-1.0 mm. wide; calyx teeth well developed; flowers white.


Fruit glabrous, oblong-ovate, longer than wide, 2.5-4 mm. long, with prominent ribs.

Accepted Name:
Perideridia oregana (S. Watson) Mathias
Publication: Brittonia 2: 243. 1936.

Synonyms & Misapplications:
Atenia oregana
Carum oregana
Additional Resources:

PNW Herbaria: Specimen records of Perideridia oregana in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Perideridia oregana checklist entry.

E-Flora BC: Perideridia oregana atlas page.

CalPhotos: Perideridia oregana photos.

USDA Plants: Perideridia oregana information.

11 photographs:
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