Juncus hemiendytus var. abjectus
Center basin rush
Family: Juncaceae · Type: Grass · Native
Conservation status: CNPS 4.3
Juncus hemiendytus var. abjectus (Center basin rush) is a native California grass in the Juncaceae family, recognized by high elevation, tiny size, and stems wider below flower.
Center basin rush is a California native annual found in the Sierra Nevada, northern Cascade Range, Modoc Plateau, and eastern Sierra Nevada in damp open areas, especially vernally wet sites, at elevations of 1,400 to 3,400 meters. Flowering details are not specified in the available data, but the plant has thin stems less than one-half millimeter wide. Growing with delicate stems that are slightly wider at the base near the flower, this rush forms small, subtle clumps in seasonal wet environments. Its stems lack bracts and produce fruits that are generally shorter than the plant's perianth. This understated annual is adapted to temporary water environments, thriving in brief windows of seasonal moisture across high elevation landscapes.
Identification and appearance
Key characters: 41 sympatric species; key features are high elevation, tiny size, and stems wider below flower
Habitat and range
Habitat: Damp open areas, especially vernally wet
Elevation: 1400-3400 m
California counties: Mono, Plumas, Tulare, Modoc, Tuolumne, Nevada, Alpine, Sierra, Lassen
Outside California: to Oregon, Idaho, Nevada
Conservation status
CNPS 4.3
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 hemiendytus var. abjectus native to California?
Yes. Juncus hemiendytus var. abjectus is native to California (recorded as native).
Where in California does Juncus hemiendytus var. abjectus grow?
Juncus hemiendytus var. abjectus occurs in Mono, Plumas, Tulare, Modoc, Tuolumne, Nevada, Alpine, Sierra and other counties, at elevations of 1400-3400 m.
What plant family does Juncus hemiendytus var. abjectus belong to?
Juncus hemiendytus var. abjectus is in the Juncaceae family, genus Juncus.
Is Juncus hemiendytus var. abjectus rare or endangered?
Juncus hemiendytus var. abjectus carries California Rare Plant Rank 4.3, state rank S4.
What habitat does Juncus hemiendytus var. abjectus grow in?
Juncus hemiendytus var. abjectus grows in Damp open areas, especially vernally wet.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.