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

Cassiope tetragona (L.) D. Don
four-angled mountain-heather (white arctic mountain heather)
Ericaceae (Crowberry family)

Introduction to Vascular Plants

© Allan Carson  Email the photographer   (Photo ID #17741)

E-Flora BC Static Map
Distribution of Cassiope tetragona
Click here to view the full 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.



General:
Coarse dwarf shrub, mat-forming; stems 4-angled, stiff, ascending to erect, 5-30 cm long, finely hairy.
Leaves:
Evergreen, opposite, distinctly in 4 rows, appressed, nearly concealing the stems, egg- to lance-shaped, 2-6 mm long, deeply grooved on the back, conspicuously finely hairy and minutely fringed on outer surface, usually glabrous or glandular on concave inner surface; unstalked.
Flowers:
Solitary in leaf axils to few near branch tips, nodding on stalks 10-25 mm long, longer than the subtending leaves; corollas white or pinkish, bell-shaped, (4) 5-10 mm long, lobes egg-shaped, almost 1/2 the length of the tube; calyces reddish, egg-shaped, 2-2.5 mm long, entire; stamens not enlarged at the base.
Fruits:
Capsules, globe-shaped, glabrous, about 3 mm wide.
Notes:
Two varieties are recognized in BC:

1. Flowers usually less than 5 (6) mm long, the flower stalks generally less than twice the length of the subtending leaves........................ var. saximontana (Small) C. L. Hitchc.

1. Flowers 6-10 mm long, the flower stalks proportionately longer, more than twice the length of the subtending leaves........................... var. tetragona

Source: The Illustrated Flora of British Columbia

USDA Species Characteristics

Flower Colour:
White
Blooming Period:
Late Spring
Fruit/Seed characteristics:
Colour: Brown
Present over the Summer
Source:  The USDA

Habitat / Range

Moist to dry meadows, heath, and rocky slopes in the subalpine and alpine zones; frequent in BC in and E of the Coast-Cascade Mountains; circumpolar, N to AK, YT, and NT, E to N PQ, and S to WA and MT; Eurasia.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Cassiope tetragona

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

Minimum

Average

Maximum

Elevation (metres) 34 1803 3000
Slope Gradient (%) 0 23 84
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 11 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 3 7
Modal Nutrient Regime
Class
C
Number of field plots
 species was recorded in:
328
Modal BEC Zone Class
BAFA
All BEC Zones (# of stations/zone) species was recorded in: AT(15), BAFA(127), CWH(1), ESSF(90), IMA(42), MH(5), SWB(30)

Ecological Indicator Information

A very shade-intolerant, alpine, circumpolar, evergreen shrub (transcontinental in North America). Occurs in continental alpine tundra and subalpine boreal climates on fresh to very moist, nitrogen-medium soils. Scattered to plentiful in heath communities affected by snow-drifts; its occurrence increases with increasing continentality. Often associated with Cassiope mertensiana and Phyllodoce glanduliflora in the coast-interior ecotone. Characteristic of alpine communities.

SourceIndicator Plants of Coastal British Columbia (Information applies to coastal locations only)

Climate

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 alpine tundra & boreal.

Taxonomic and Nomenclatural Links

Additional Photo Sources

Related Databases

General References