Juncus usitatus
Australian rush, Australian Rush
(c) Greg Tasney, some rights reserved (CC BY-SA) · licence
Family: Juncaceae · Type: Perennial · Not Native
Juncus usitatus (Australian rush) is a non-native California perennial in the Juncaceae family, recognized by non-native status, rough ridged stems, and tiny flowers diagnostic.
Australian rush is a naturalized perennial found in the northern Sierra Nevada Foothills, Sacramento Valley, and northern San Joaquin Valley in ponds, floodplains, seeps, and wet disturbed ground at elevations below 350 meters. Flowering details are not specified in the source data. Growing with dense, clustered stems up to 115 centimeters tall and 1 to 4.7 millimeters wide, this rush has rough stems with up to 25 fine ridges on each side when dry. Its upper leaf sheaths are 8 to 22 centimeters long, with shiny dark-brown bases transitioning to green or pale brown, and thin, flat pale margins that overlap halfway up the stem. The plant produces tiny perianth segments that are green, pale brown, or slightly reddish, with wide scarious margins and three stamens.
Identification and appearance
Key characters: 39 sympatric species; non-native status, rough ridged stems, and tiny flowers diagnostic
Habitat and range
Habitat: Ponds, floodplains, seeps, wet disturbed ground
Elevation: < 350 m
Outside California: Australia, New Zealand, introduced in United Kingdom
How to tell it apart
vs Schoenoplectus: Juncus has leaf blades present; Schoenoplectus is leafless with only bladeless sheaths at base.; vs Carex: Juncus has round or flattened stems; Carex has triangular stems you can feel.; vs Luzula: Run finger along leaf edge - smooth = Juncus, hairy = Luzula.; vs Elegia: Juncus has small individual flowers; Elegia has showy papery bracts and branching structure.; vs Cyperus: Juncus has round stems and capsules; Cyperus has triangular stems and lens-shaped achenes.
Frequently asked questions
Is Juncus usitatus native to California?
No. Juncus usitatus is not native to California (recorded as not native).
What plant family does Juncus usitatus belong to?
Juncus usitatus is in the Juncaceae family, genus Juncus.
What habitat does Juncus usitatus grow in?
Juncus usitatus grows in Ponds, floodplains, seeps, wet disturbed ground.
Related species
Other California species in the same genus, family, or bioregion.
- Juncus xiphioides — Iris-leaved rush
- Juncus acuminatus — Tapered rush
- Juncus acutus subsp. leopoldii — Southwestern spiny rush
- Juncus ambiguus — Frog rush
- Juncus anthelatus — Kentucky or poverty rush
- Juncus articulatus subsp. articulatus — Jointed rush
- Luzula cascadensis
- Luzula comosa — Common wood rush
- Luzula comosa var. comosa — Hairy wood rush
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.