Page authors: Don Knoke, David Giblin
Perideridia montana
mountain yampah

Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains and northern Great Plains.

Habitat: Woodland edge, balds, prairies, outcroppings, and vernally wet meadows from the lowlands to middle elevations in the mountains.

Flowers: July-September

Origin: Native

Growth Duration: Perennial

Conservation Status: Not of concern


Slender, glabrous perennial from a tuberous-thickened, edible, usually solitary root, the solitary stem 4-12 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 bristly bractlets, or wanting; calyx teeth well developed; flowers white.


Fruit glabrous, sub-orbicular, 2-3 mm. long and wide, with prominent ribs.

Accepted Name:
Perideridia montana (Blank.) Dorn
Publication: Vasc. Pl. Wyoming 295. 1988.

Synonyms & Misapplications:
Atenia montana (Blank.) Rydb.
Carum garrettii A. Nelson ex Coult. & Rose [IMF]
Carum montanum Blank.
Perideridia gairdneri (Hook. & Arn.) Mathias, misapplied [HC]
Perideridia gairdneri (Hook. & Arn.) Mathias ssp. borealis T.I. Chuang & Constance [HC, JPM2]
Perideridia gairdneri (Hook. & Arn.) Mathias var. montana (Blank.) B. Boivin [IMF]
Additional Resources:

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

WA Flora Checklist: Perideridia montana checklist entry.

E-Flora BC: Perideridia montana atlas page.

CalPhotos: Perideridia montana photos.

USDA Plants: Perideridia montana information.

53 photographs:
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