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

Linnaea borealis L.
twinflower
Caprifoliaceae (Valerian family)

Introduction to Vascular Plants

© Rosemary Taylor  Email the photographer   (Photo ID #40616)

E-Flora BC Static Map
Distribution of Linnaea borealis
Click here to view the full interactive map and legend
Details about map content are available here
New! 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:
Evergreen, creeping, semiwoody herb or subshrub; stems long, slender, weakly rooting, thinly hairy and often also glandular, producing numerous short (less than 10 cm tall), more or less erect, leafy stems or branchlets with 2-4 pairs of leaves.
Leaves:
Opposite, simple, short-stalked, egg-shaped to nearly circular, with a few shallow teeth along the upper half, 7-25 mm long, 5-15 mm wide, leathery, dark green above, paler below, glabrous or the stalks and margins of the leaf bases often fringed with long hairs.
Flowers:
Inflorescence of nodding pairs of flowers on slender, erect, Y-shaped stalks that terminate the leafy branchlets; base of flowers cradled by two tiny bracts; corollas slenderly funnel-shaped, 9-16 mm long, pink to whitish, flaring above to 5 lobes, hairy in the throat; styles about as long as corollas, with a tiny knoblike stigma; stamens 4.
Fruits:
Dry 1-seeded achenes (nutlets), flanked by a pair of tiny glandular bracts.
Notes:
Two subspecies occur in BC:

1. Corollas 9-11 mm long, narrowly bell-shaped, flaring from within the calyces, tubes very short or sometimes absent................... ssp. borealis

1. Corollas 10-16 mm long, funnel-shaped, tubes about equalling or surpassing the calyces...................ssp. longiflora (Torr.) Hult.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Mesic forests in the lowland and montane zones; ssp. longiflora common throughout BC; ssp. borealis infrequent in extreme NW BC; ssp. borealis - circumboreal, N to AK and YT, ssp. longiflora - N to AK, YT and NT, E to NF and S to IN, NM and CA.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Linnaea borealis

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) 0 982 2500
Slope Gradient (%) -2 18 262
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 221 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 3 8
Modal Nutrient Regime
Class
C
Number of field plots
 species was recorded in:
15579
Modal BEC Zone Class
ICH
All BEC Zones (# of stations/zone) species was recorded in: AT(2), BWBS(1567), CDF(86), CWH(1392), ESSF(1248), ICH(3302), IDF(1495), MH(59), MS(1857), PP(13), SBPS(523), SBS(2842), SWB(223)

Ecological Indicator Information

A shade-tolerant/intolerant, submontane to subalpine, circumpolar evergreen shrub (transcontinental in North America). Occurs predominantly on moderately dry to fresh soils within boreal, cool temperate, and cool mesothermal climates. Scattered to plentiful in mossy understories in coniferous forests on water­shedding sites: on moist and wet sites it inhabits topographic prominences, on nutrient-rich sites it is restricted to decaying coniferous wood; persists on undisturbed cutover sites. Commonly associated with Cornus canadensis, Goodyera oblongifolia, Hylocomium splendens, Kinbergia oregana, and Vaccium parvifolium. Characteristic of Moder and acidic Moder humus forms.

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 not evaluated, unknown or variable.

Synonyms and Alternate Names

Linnaea americana Forbes
Linnaea borealis var. americana (Forbes) Rehder

Taxonomic and Nomenclatural Links

Additional Photo Sources

Related Databases

General References