Epipactis gigantea Douglas ex Hook.
giant helleborine (stream orchid)
Orchidaceae (Orchid family)

Introduction to Vascular Plants

Photograph

© Ian Gardiner     (Photo ID #16059)


Map

E-Flora BC Static Map

Distribution of Epipactis gigantea
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Introduction

Giant Helleborine is a large, perennial, rhizomatous orchid species that in North America is found in the western half of the continental United States and in one Canadian province (British Columbia) (USDA 2011). In British Columbia, it is found in the southern part of the province, in "moist streambanks, fens, marshes and swamps, and around hot springs in the lowland and montane zones" (Douglas et al. 2001).

Lomer (2011) describes this species in the Fraser Valley: "This robust orchid of wet, often calcareous sites, was known in the Fraser Valley from Cultus Lake where it was collected more than 70 years ago (UBC: H.H. Rose s.n.). It was rediscovered there in 2004 (UBC: Lomer 5404). It is quite frequent along the northern lakeshore for 100 meters. It is not yet threatened on this undeveloped side of Cultus Lake, though the near-constant summertime wave action caused by boaters is battering the shoreline plants. In 2009 a large population of E. gigantea was discovered by Monica Pearson in a wetland east of Agassiz. As well, a few small patches exist on the Fraser River islands southwest of Agassiz. Surprisingly, these plants are not in wet sites in summer, but are moistened or even inundated during high runoff." [Originally reprinted from Botanical Electronic News # 435, with permission.]

Species Information

General:
Perennial herb from short rhizomes and clustered, thickened roots; stems 30-100 cm tall, leafy, sparsely hairy.
Leaves:
Stem leaves lanceolate to widely elliptic, 5-15 cm long, ribbed, gradually reduced upward and downward.
Flowers:
Inflorescence terminal, somewhat 1-sided, of several showy flowers, the bracts leaflike; sepals green to reddish, purple-veined, lanceolate to egg-shaped, 12-20 mm long, the lower sepals spreading to descending; lateral petals similar to sepals, 13-15 mm long, ascending or curved forward; lip 14-20 mm long, saclike at base, 3-lobed, lower half deeply concave, greenish to yellowish, red-purple-veined, upper half grooved, yellow, reddish-tinged or -veined below; column 5-9 mm long, curved over lip.
Fruits:
Capsules, ellipsoid, spreading to drooping, 2-3 cm long.

SourceThe Illustrated Flora of British Columbia

Illustration

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Habitat and Range

Moist streambanks, fens, marshes and swamps, and around hot springs in the lowland and montane zones; rare in S BC; S to TX, NM, AZ and CA.

SourceThe Illustrated Flora of British Columbia