Eleocharis engelmannii var. detonsa
Engelmann's spikerush
(c) Matthew Sirotkin, some rights reserved (CC BY) · licence
Family: Cyperaceae · Type: Annual · Native
Eleocharis engelmannii var. detonsa (Engelmann's spikerush) is a native California annual in the Cyperaceae family, recognized by 22 co-occurring species; absence of fruit bristles.
Engelmann's spikerush is a native annual found in northwestern California, the high Cascade Range, Sierra Nevada, and Modoc Plateau, particularly in Grasshopper Valley, Lassen County, growing on fresh wet bare soil at elevations of 30 to 2,400 meters. Flowering from spring through fall, this delicate spikerush produces small, inconspicuous flowers in narrow, elongated spikes. Growing with slender, bright green stems up to 30 centimeters tall, it forms dense, compact clusters in moist environments. Its leaves are reduced to sheaths at the base of the stem, characteristic of spikerush species. The fruit is distinguished by nearly absent or vestigial perianth bristles, giving the plant a smooth, minimalist appearance.
Identification and appearance
Key characters: 22 co-occurring species; absence of fruit bristles is diagnostic
Habitat and range
Habitat: Fresh wet bare soil
Elevation: 30-2400 m
Bloom period
Eleocharis engelmannii var. detonsa blooms Spring-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 engelmannii var. detonsa native to California?
Yes. Eleocharis engelmannii var. detonsa is native to California (recorded as native).
When does Eleocharis engelmannii var. detonsa bloom?
Eleocharis engelmannii var. detonsa blooms Spring-fall.
What plant family does Eleocharis engelmannii var. detonsa belong to?
Eleocharis engelmannii var. detonsa is in the Cyperaceae family, genus Eleocharis.
What habitat does Eleocharis engelmannii var. detonsa grow in?
Eleocharis engelmannii var. detonsa grows in Fresh wet bare soil.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.