Atriplex dioica
Thickleaf orach, Thickleaf Orach
(c) Matt Lavin, some rights reserved (CC BY-SA) · licence
Family: Chenopodiaceae · Type: Herb · Native
Atriplex dioica (Thickleaf orach) is a native California herb in the Chenopodiaceae family, recognized by large size, long-petioled hastate leaves, and spongy fruit bracts.
Thickleaf orach is a California native annual found in southern Sacramento Valley, San Joaquin Valley, central Coast, San Francisco Bay, and southern California coastal areas in moist, saline or alkaline soils at elevations below 200 meters. Flowering from July to November, this plant produces green to reddish flowers with distinctive triangular to lance-shaped leaves. Growing 50 to 150 centimeters tall with branching stems that are reddish at the base and green-streaked, the plant has an upright, spreading form. Its leaves are 2 to 8 centimeters long, triangular to lance-shaped, sometimes with a slightly arrowhead-shaped base, ranging from entirely green to partially reddish. The plant produces two kinds of seeds, with black seeds about 1.5 to 2 millimeters wide and brown seeds 2 to 3 millimeters wide.
Identification and appearance
Key characters: 39 sympatric species; large size, long-petioled hastate leaves, and spongy fruit bracts are diagnostic
Habitat and range
Habitat: Moist, saline or alkaline soils
Elevation: < 200 m
Outside California: to eastern North America
Bloom period
Atriplex dioica blooms Jul-Nov.
How to tell it apart
vs Artemisia: Atriplex leaves have bead-like scales; Artemisia leaves are finely divided and aromatic when crushed.; vs Ambrosia: Atriplex has simple scaly leaves; Ambrosia has deeply lobed or divided leaves with coarse hairs.; vs Extriplex: Atriplex has 3-5 calyx lobes on male flowers and two seed colors; Extriplex has exactly 4 lobes and uniform dark seeds.; vs Chenopodium: Atriplex has bead-like bladder hairs and paired fruit bracts; Chenopodium has mealy powder and calyx-enclosed fruits.; vs Eriogonum: Atriplex has scaly leaves and paired fruit bracts; Eriogonum has smooth leaves and papery flower tubes.
Frequently asked questions
Is Atriplex dioica native to California?
Yes. Atriplex dioica is native to California (recorded as native).
When does Atriplex dioica bloom?
Atriplex dioica blooms Jul-Nov.
What plant family does Atriplex dioica belong to?
Atriplex dioica is in the Chenopodiaceae family, genus Atriplex.
What habitat does Atriplex dioica grow in?
Atriplex dioica grows in Moist, saline or alkaline soils.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.