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

Platanthera orbiculata (Pursh) Lindl.
large round-leaved rein orchid (lesser roundleaved orchid)
Orchidaceae (Orchid family)

Introduction to Vascular Plants

© Virginia Skilton  Email the photographer   (Photo ID #7071)

E-Flora BC Static Map
Distribution of Platanthera orbiculata
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:
Perennial herb, from fleshy, spindle-shaped stem-bases, with a few fibrous roots; stems 20-50 cm tall, without leaves, with 1-5 lance-shaped bracts.
Leaves:
Pair of basal leaves, opposite or nearly so, often lying on ground, round to oblong-elliptic, usually 6-16 cm long, 3-14 cm wide.
Flowers:
Inflorescence a terminal, loosely 5- to 25-flowered spike, bracted, the bracts shorter than the flowers; flowers whitish-green, the stalks 3-7 mm long; lower sepals 8-13 mm long, triangular to broadly lanceolate, somewhat bent back, the upper sepal kidney-shaped to broadly egg-shaped, 4-8 mm long, erect; petals shorter and lighter than sepals, egg-shaped to broadly lanceolate, bent back; lip 10-20 mm long, strap-shaped, whitish, hanging downward with slightly up-curved tip; spur somewhat club-shaped, curved, 15-25 mm long; column 4-5 mm long.
Fruits:
Capsules, erect, curved, to 20 mm long.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Dry to moist forests, bogs and swamps in the montane zone; infrequent in BC south of 55 degrees N, except rare on the coast; N to AK, YT and NT, E to NF and S to ME, MA, PA, NC, TN, MN, SD, MT, ID and WA.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Platanthera orbiculata

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) 8 745 2500
Slope Gradient (%) 0 14 205
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 185 360
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:
1111
Modal BEC Zone Class
ICH
All BEC Zones (# of stations/zone) species was recorded in: BWBS(123), CDF(12), CWH(86), ESSF(17), ICH(378), IDF(23), MH(10), MS(19), SBPS(54), SBS(349), SWB(1)

Ecological Indicator Information

A shade-tolerant, montane to subalpine, transcontinental North American forb (rare in the Pacific region). Occurs in continental boreal and cool temperate climates on moderately dry to fresh, nitrogen-poor soils; its occurrence increases with increasing continentality. Scattered in the mossy understory of semi-open coniferous forests on water-shedding sites in the coast-interior ecotone. Usually associated with Clintonia uniflora, Pleurozium schreberi, Ptilium crista-castrensis, Rhytidiopsis robusta, and Vaccinium membranaceum. An oxylophytic species characteristic of Mar 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 montane boreal & cool temperate.

Synonyms and Alternate Names

Habenaria orbiculata (Pursh) Torr.
Habenaria orbiculata var. lehorsii Fern.
Habenaria orbiculata var. menziesii (Lindl.) Fern.
Lysias orbiculata (Pursh) Rydb.

Taxonomic and Nomenclatural Links

Additional Photo Sources

Related Databases

General References