Juncus interior
Inland rush
(c) Nathan Aaron, some rights reserved (CC BY), uploaded by Nathan Aaron · licence
Family: Juncaceae · Type: Grass · Native
Conservation status: CNPS 2B.2
Juncus interior (Inland rush) is a native California grass in the Juncaceae family, recognized by desert mountain habitat, erect perianth in fruit, and fruit longer than perianth.
Inland rush is a rare (CNPS 2B.2) California native perennial found in the San Bernardino Mountains in granitic washes at elevations of 1,800 to 1,900 meters. Flowering in summer months, this rush produces small green to pale brown flowers in clustered, slightly open inflorescences. Growing in dense tufts 11 to 60 centimeters tall with upright stems, it forms compact clumps in rocky mountain habitats. Its leaves are narrow, flat, and 0.5 to 1.1 millimeters wide, with membranous sheaths and minimal leaf appendages. The plant produces small ellipsoid fruits that are typically longer than its perianth, with minute, blunt seed appendages.
Identification and appearance
Key characters: 14 sympatric species; key features are desert mountain habitat, erect perianth in fruit, and fruit longer than perianth
Habitat and range
Habitat: Granitic washes
Elevation: 1800-1900 m
California counties: San Bernardino
Outside California: Arizona to British Columbia, Ontario, Tennessee
Conservation status
CNPS 2B.2
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 interior native to California?
Yes. Juncus interior is native to California (recorded as native).
Where in California does Juncus interior grow?
Juncus interior occurs in San Bernardino, at elevations of 1800-1900 m.
What plant family does Juncus interior belong to?
Juncus interior is in the Juncaceae family, genus Juncus.
Is Juncus interior rare or endangered?
Juncus interior carries California Rare Plant Rank 2B.2, state rank S1.
What habitat does Juncus interior grow in?
Juncus interior grows in Granitic washes.
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.