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

Listera convallarioides (Sw.) Nutt. ex Elliott
broad-leaved twayblade (broadlipped twayblade)
Orchidaceae (Orchid family)

Introduction to Vascular Plants

© Jim Riley  Email the photographer   (Photo ID #767)

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Distribution of Listera convallarioides
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Species Information

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Perennial herb from slender rhizomes, with fibrous roots; stems 10-35 cm tall, with 2 leaves, glandular-hairy above.
Two, near middle of stem, roughly opposite, elliptic to broadly egg-shaped or nearly circular, 2-7 cm long, 1.5-6 cm wide, smooth, abruptly tapered to base.
Inflorescence a many-flowered, terminal raceme, the flowers yellowish-green; sepals 4.5-6 mm long, narrowly lanceolate, 1-veined, distinct; petals similar to sepals but narrower, 4-5 mm long; lip 8-13 mm long, 5-7 mm wide at tip, broadly wedge-shaped, with a shallow notch at tip, base with a short triangular tooth on each side, short-clawed; column 2.5-3.5 mm long.
Capsules, spreading, egg-shaped, to 4 mm long.

Source: The Illustrated Flora of British Columbia

USDA Species Characteristics

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

Habitat / Range

Moist forests, bogs and streambanks in the montane zone; infrequent in BC south of 54 degrees N, rare in NW BC; amphiberingian, N to AK, E to NF and S to ME, NH, MI, WI, MN, SD, CO, AZ and CA; E Asia.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Listera convallarioides

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) 5 951 1866
Slope Gradient (%) 0 21 150
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 197 359
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 4 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: BWBS(1), CWH(46), ESSF(23), ICH(74), IDF(1), MH(22), MS(4), SBS(7)

Ecological Indicator Information

A shade-tolerant, submontane to montane, Asian and transcontinental North American forb. Occurs in cool temperate and cool mesothermal climates on fresh to very moist, nitrogen-rich soils: its occurrence decreases with increasing elevation and continentality. Sporadic in semi-terrestrial communities on water­collecting sites: occasionally associated with Lysichitum americanum. A nitrophytic species characteristic of Moder and Mull humus forms.

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


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 cool temperate & cool mesothermal.

Synonyms and Alternate Names

Ophrys convallarioides (Sw.) W. Wight

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References