Rumex lacustris
Lake dock
(c) Tim Messick, some rights reserved (CC BY), uploaded by Tim Messick · licence
Family: Polygonaceae · Type: Perennial · Native
Rumex lacustris (Lake dock) is a native California perennial in the Polygonaceae family, recognized by . Specialized aquatic/saline habitat and geographic restriction distinctive.
Lake dock is a native perennial found in the Great Basin Mountains, particularly in the Mono Pass region, inhabiting beds and shores of slightly salty lakes at elevations of 1,000 to 2,500 meters. Flowering from March to June, this plant produces small flowers in dense, interrupted whorls with branches clustered along the stem. Growing 4 to 7 decimeters tall with decumbent to erect stems that feature axillary shoots, it develops a distinctive vertical or creeping taproot. Its lance-ovate leaves measure 3 to 7 centimeters long, with terrestrial leaves featuring a papillate hairy undersurface and margins that can be flat or slightly wavy. The fruit is small, measuring 1.5 to 2.2 millimeters long and appearing brown or dark red-brown.
Identification and appearance
Key characters: 12 sympatric species. Specialized aquatic/saline habitat and geographic restriction distinctive.
Habitat and range
Habitat: Beds, shores of +- salty lakes
Elevation: 1000-2500 m
Outside California: Oregon, Nevada
Bloom period
Rumex lacustris blooms Mar-Jun.
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 lacustris native to California?
Yes. Rumex lacustris is native to California (recorded as native).
When does Rumex lacustris bloom?
Rumex lacustris blooms Mar-Jun.
What plant family does Rumex lacustris belong to?
Rumex lacustris is in the Polygonaceae family, genus Rumex.
What habitat does Rumex lacustris grow in?
Rumex lacustris grows in Beds, shores of +- salty lakes.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.