Carex unilateralis

One-sided sedge, One-Sided Sedge

Carex unilateralis (One-sided sedge), native California grass

(c) Trevor Van Loon, some rights reserved (CC BY) · licence

Family: Cyperaceae · Type: Grass · Native

Carex unilateralis (One-sided sedge) is a native California grass in the Cyperaceae family, recognized by distinctive pseudolateral inflorescence.

One-sided sedge is a California native perennial found in northern coastal and northern coastal ranges of California in seasonally wet places at elevations below 1,000 meters. Flowering in spring and early summer, this sedge produces subtle gold to reddish-brown flower spikelets in dense clusters 10 to 25 millimeters long. Growing with slender stems 10 to 30 centimeters tall, it forms compact tufts with narrow upright leaves. Its leaves are distinctively narrow, measuring 2 to 5 millimeters wide, with ligules 2.5 to 8 millimeters long that appear leaf-like and clasping the stem. The fruit develops as small perigynia 1.5 to 1.9 millimeters long, with an ascending ovate shape and delicate green to gold coloration.

Identification and appearance

Key characters: 66 sympatric species; distinctive pseudolateral inflorescence

Habitat and range

Habitat: Seasonally wet places

Elevation: < 1000 m

California counties: Mendocino, Humboldt, Trinity, Lake, Mariposa

Outside California: to British Columbia

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 unilateralis native to California?

Yes. Carex unilateralis is native to California (recorded as native).

Where in California does Carex unilateralis grow?

Carex unilateralis occurs in Mendocino, Humboldt, Trinity, Lake, Mariposa, at elevations of < 1000 m.

What plant family does Carex unilateralis belong to?

Carex unilateralis is in the Cyperaceae family, genus Carex.

What habitat does Carex unilateralis grow in?

Carex unilateralis grows in Seasonally wet places.

Related species

Other California species in the same genus, family, or bioregion.

All Carex species · All Cyperaceae

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.