Page author: David Giblin
Rumex occidentalis
western dock, western dock o n

Distribution: Distributed on both sides of the Cascades in Washington; Alaska south to central California, east to North Dakota and New Mexico.

Habitat: Moist to swampy areas and wet meadows, from the sea coast to foothill valleys.

Flowers: June-August

Origin: Native

Growth Duration: Perennial

Conservation Status: Not of concern

Pollination: Wind


Usually glabrous perennial from a strong taproot, the stem usually single, erect, stout, unbranched below the inflorescence, reddish-tinged, 10-20 dm. tall.


Basal leaves several, with sheathing stipules and long petioles, the blade oblong-ovate or oblong-lanceolate, 10-30 cm. long, cordate at base; cauline leaves few, much reduced upward.


Inflorescence a large panicle, leafy-bracteate below, the branches ascending; pedicels slender, 2-3 times as long as the flowers; flowers perfect; outer 3 perianth segments 1.5-2 mm. long, not reflexed; inner 3 segments triangular to oval, 3-11 mm. long, truncate at base, entire or denticulate on the margins, strongly veiny; styles 3.


Achene about 4 mm. long, smooth.

Accepted Name:
Rumex occidentalis S. Watson
Publication: Proc. Amer. Acad. Arts. 12: 253. 1877. 1877.

Synonyms & Misapplications:
Rumex aquaticus L. ssp. occidentalis (S. Watson) Hultén
Rumex aquaticus L. var. fenestratus (Greene) Dorn [ILBC4]
Rumex bakeri Greene
Rumex confinis
Rumex fenestratus Greene
Rumex fenestratus Greene var. labradoricus Rech. f.
Rumex gracilipes Greene
Rumex occidentalis S. Watson var. labradoricus (Rech. f. ) Lepage
Rumex occidentalis S. Watson var. procerus (Greene) J.T. Howell [HC]
Rumex procerus
Additional Resources:

PNW Herbaria: Specimen records of Rumex occidentalis in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Rumex occidentalis checklist entry.

OregonFlora: Rumex occidentalis information.

E-Flora BC: Rumex occidentalis atlas page.

CalPhotos: Rumex occidentalis photos.

USDA Plants: Rumex occidentalis information.

35 photographs:
Group by