Eleocharis flavescens var. flavescens
Yellow spikerush
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Family: Cyperaceae · Type: Grass · Native
Eleocharis flavescens var. flavescens (Yellow spikerush) is a native California grass in the Cyperaceae family, recognized by 21 co-occurring species; brackish/saline habitat and inflated sheath tips.
Yellow spikerush is a California native perennial found in northern Sierra Nevada and Great Valley bioregions in wet sand, gravel, marshes, and salt flats at elevations below 1,600 meters. Flowering from summer to fall, this plant produces subtle greenish-yellow flowers in compact spikes 1.5 to 9 millimeters long. Growing with slender cylindrical stems 5 to 42 centimeters tall, it emerges from a thin, firm rhizome and forms delicate clumps in wet environments. Its leaves have distinctive inflated, wrinkled sheaths that often disintegrate, with the stem appearing nearly threadlike and approximately 0.3 to 0.6 millimeters in diameter. The fruit is tiny, smooth, and two-sided, with vestigial perianth bristles that may extend slightly beyond the fruit itself.
Identification and appearance
Key characters: 21 co-occurring species; brackish/saline habitat and inflated sheath tips are diagnostic
Habitat and range
Habitat: Rare in California. Wet sand, gravel, marsh, brackish canals, hot springs, maritime mud flats, salt marshes
Elevation: < 1600 m
California counties: Merced, El Dorado, Kern, Tehama, Stanislaus
Outside California: to Montana, Virginia, Florida, West Indies, South America
Bloom period
Eleocharis flavescens var. flavescens blooms Summer-fall.
How to tell it apart
vs Carex: Eleocharis has single spikelet with no bracts below, Carex has leafy bracts and multiple spikes.; vs Isolepis: Eleocharis has no bracts below spikelet, Isolepis has conspicuous leaf-like bracts extending beyond flowers.; vs Schoenoplectus: Eleocharis has single terminal spikelet, Schoenoplectus has multiple spikelets in clusters.; vs Juncus: Eleocharis spikelets are flattened oval, Juncus flowers are round with visible petals in clusters.; vs Equisetum: Eleocharis has grass-like stems with flower spikelets, Equisetum has jointed hollow stems with cone-like structures.
Frequently asked questions
Is Eleocharis flavescens var. flavescens native to California?
Yes. Eleocharis flavescens var. flavescens is native to California (recorded as native).
When does Eleocharis flavescens var. flavescens bloom?
Eleocharis flavescens var. flavescens blooms Summer-fall.
Where in California does Eleocharis flavescens var. flavescens grow?
Eleocharis flavescens var. flavescens occurs in Merced, El Dorado, Kern, Tehama, Stanislaus, at elevations of < 1600 m.
What plant family does Eleocharis flavescens var. flavescens belong to?
Eleocharis flavescens var. flavescens is in the Cyperaceae family, genus Eleocharis.
What habitat does Eleocharis flavescens var. flavescens grow in?
Eleocharis flavescens var. flavescens grows in Rare in California. Wet sand, gravel, marsh, brackish canals, hot springs, maritime mud flats, salt marshes.
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.