Rumex triangulivalvis
Willow dock
(c) Louis Imbeau, some rights reserved (CC BY), uploaded by Louis Imbeau · licence
Family: Polygonaceae · Type: Perennial · Native
Rumex triangulivalvis (Willow dock) is a native California perennial in the Polygonaceae family, recognized by . Mountain/inland distribution and small, equal tubercles help separate from other willow docks.
Willow dock is a California native perennial found in the northern Sierra Nevada, central Sierra Nevada, Sutter Buttes, southern California's Great Basin, and Great Basin regions in many habitats, often in marginal or disturbed areas at elevations below 3,000 meters. Flowering from April to July, this plant produces small, inconspicuous greenish-brown flowers in dense, interrupted whorls along branching stems. Growing 3 to 10 decimeters tall with ascending to erect stems that develop axillary shoots, it forms a vertical taproot with short or absent rhizomes. Its leaves are linear to lanceolate, 6 to 17 centimeters long and 1 to 4 centimeters wide, with entire margins that may appear flat or slightly wavy. The fruit is small, measuring 1.7 to 2.2 millimeters long and ranging from brown to dark red-brown.
Identification and appearance
Key characters: 18 sympatric species. Mountain/inland distribution and small, equal tubercles help separate from other willow docks.
Habitat and range
Habitat: Many habitats, often marginal or disturbed
Elevation: < 3000 m
California counties: Lassen, Plumas, Mono, Modoc, El Dorado, Fresno, Kern, Madera, Riverside, Shasta, Sierra, Siskiyou, Tehama, Alpine, Butte, Inyo, Mariposa, Nevada, Placer, San Bernardino, Tulare, Tuolumne, Trinity, Del Norte, Sacramento
Outside California: North America, Mexico, naturalized in Europe
Bloom period
Rumex triangulivalvis blooms Apr-Jul.
How to tell it apart
vs Anemopsis: Rumex has dense flower clusters; Anemopsis has a single white cone-like flower head.; vs Amaranthus: Rumex has papery three-winged fruits; Amaranthus has small round seeds with papery covers.; vs Plantago: Rumex has branching flower clusters; Plantago has flowers in dense cylindrical spikes.; vs Eriogonum: Rumex has large broad leaves; Eriogonum typically has small basal leaf rosettes or mats.; vs Limonium: Rumex has green to reddish flower clusters; Limonium has papery purple or pink flowers.
Frequently asked questions
Is Rumex triangulivalvis native to California?
Yes. Rumex triangulivalvis is native to California (recorded as native).
When does Rumex triangulivalvis bloom?
Rumex triangulivalvis blooms Apr-Jul.
Where in California does Rumex triangulivalvis grow?
Rumex triangulivalvis occurs in Lassen, Plumas, Mono, Modoc, El Dorado, Fresno, Kern, Madera and other counties, at elevations of < 3000 m.
What plant family does Rumex triangulivalvis belong to?
Rumex triangulivalvis is in the Polygonaceae family, genus Rumex.
What habitat does Rumex triangulivalvis grow in?
Rumex triangulivalvis grows in Many habitats, often marginal or disturbed.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.