E-Flora BC: Electronic Atlas of the Flora of British Columbia

Carex atratiformis Britton
black sedge (scrabrous black sedge)
Cyperaceae (Sedge family)

Introduction to Vascular Plants

© Jamie Fenneman  Email the photographer   (Photo ID #26123)

E-Flora BC Static Map
Distribution of Carex atratiformis
Click here to view our interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.

Perennial, tufted herb from short rhizomes; stems 30-70 cm tall, exceeding the leaves.
Sheaths reddish towards the bases; blades flat, with rolled-under margins, 3-5 mm wide, the lower ones not much reduced.
Spikes 3 to 6, the terminal with both female and male flowers, the female ones towards the tips, the lower 2 to 5 spikes with female flowers, stalked and nodding, 1-2.5 cm long; bracts subtending the spikes short-sheathing, leaflike, about equalling the spikes.
Perigynia broadly egg-shaped, 2.5-4 mm long, 1.3-1.8 mm wide, with rounded margins above, greenish-brown to reddish-black, flat, nerveless, the beaks short, shallowly bidentate, less than 0.4 mm long; female scales lanceolate, usually shorter than and nearly as wide as the perigynia, pointed at the tips, light to dark brown, with translucent margins; stigmas 3; achenes 3-angled, egg-shaped, granular, 1.2-1.4 mm long.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Moist forests, thickets, meadows and streambanks in the montane zone; frequent in N BC; N to AK, YT and NT, disjunct E to NF and S to MA, NH, NY and MI.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Carex atratiformis

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) 1780 2026 2320
Slope Gradient (%) 0 8 20
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
15 19 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
3 5 7
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: ESSF(3)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Synonyms and Alternate Names

Carex atratiformis subsp. raymondii (Calder) A.E. Porsild
Carex raymondii Calder

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References