Carex filifolia
Thread leaf sedge
(c) Matt Lavin, some rights reserved (CC BY-SA) · licence
Family: Cyperaceae · Type: Grass · Native
Carex filifolia (Thread leaf sedge) is a native California grass in the Cyperaceae family.
Thread leaf sedge is a California native perennial sedge found in alpine and subalpine regions at high elevations. Flowering from June to August, this plant produces pale red-brown flowers with white or yellow-brown margins in a single terminal spikelet. Growing in dense tufts with extremely thin, quill-like leaves less than one millimeter wide, it forms compact clumps with distinctive black persistent styles. Its narrow leaves are tightly rolled, creating a delicate, thread-like appearance that gives the plant its distinctive character. The fruit is small, approximately 1.6 to 3 millimeters long, with pale white to gold perigynia that are slightly hairy just below the beak.
Identification and appearance
Key characters: Geographically isolated - no sympatric species
Habitat and range
California counties: Tulare, Inyo, Tuolumne, Mono, Shasta, Modoc, Placer, Alpine, Nevada, Mariposa, Lassen, Fresno, El Dorado
How to tell it apart
vs Juncus: Carex stems are triangular when rolled; Juncus stems are round and often hollow with partitions inside.; vs Cyperus: Carex has seeds in individual flasks; Cyperus has umbrella-like flower clusters with flattened ribbon-like spikes.; vs Plantago: Carex has triangular stems and brown/green spikelets; Plantago has round flower stalks and white/brown spike flowers.; vs Eleocharis: Carex has leaves along the stem; Eleocharis is nearly leafless with just one spikelet per stem.; vs Schoenoplectus: Carex has leafy stems and flask-enclosed seeds; Schoenoplectus has leafless round stems with exposed seeds.
Frequently asked questions
Is Carex filifolia native to California?
Yes. Carex filifolia is native to California (recorded as native).
Where in California does Carex filifolia grow?
Carex filifolia occurs in Tulare, Inyo, Tuolumne, Mono, Shasta, Modoc, Placer, Alpine and other counties.
What plant family does Carex filifolia belong to?
Carex filifolia is in the Cyperaceae family, genus Carex.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · 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.