Isolepis cernua (Vahl) Roem. & Schult.
low clubrush (low bulrush)
Cyperaceae (Sedge family)

Introduction to Vascular Plants


© Jeff Bertoia     (Photo ID #32483)


E-Flora BC Static Map

Distribution of Isolepis cernua
Click here to view the full interactive map and legend

Species Information

Annual, tufted herb; stems numerous, slender, 3-20 (35) cm tall.
One to few near the bases, variously developed in different plants, sometimes with normal sheaths and blades; blades elongate, slender, up to as long as the stem, sometimes the lower ones reduced to scales, the uppermost ones with sheaths and very short blades.
Spikes solitary, appearing terminal or subterminal, often set at an angle to the stems, several- to many-flowered, 2-5.5 mm long; involucral bracts solitary, conspicuous, appearing merely as enlarged scales with broad, blunt awn tips, about 1 mm long or leaf like and up to about 1 cm long, nearly equal to or surpassing the spikes.
Scales numerous, often reddish-tinged, obscurely to evidently nerved with fine parallel lines mostly 1.2-2 mm long, the midribs tending to be enlarged, greenish or pale, often very shortly exserted as minute tips; perianth bristles lacking, but the filaments sometimes persisting and appearing like slender, flattened bristles; achenes broad, 3-angled, pale reddish-brown, dull, smooth, 1 mm long or less, with more or less abruptly, sharp-pointed tips.

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.


Ecological Framework for Isolepis cernua

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
652 518 725
Slope Gradient (%)
21 0 60

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

102 30 174
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 3 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

BWBS(1), CDF(1), MH(1), SBS(1)

Habitat and Range

Marshes, tidal flats and beaches in the lowland zone; frequent in SW BC, rare northward along the coast; S to TX and CA; cosmopolitan, Eurasia, S America, Australia and New Zealand.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Scirpus cernuus Vahl p.p.
Scirpus cernuus subsp. californicus (Torr.) Thorne
Scirpus cernuus var. californicus (Torr.) Beetle