An introduced European orchid that thrives in a variety of habitats: most types of forests from young to mature and from deciduous to coniferous relatively open at ground level with little other vegetation nearby. Also found in wet-mesic soils of swamps and stream edges, gravelly roadsides, sheltered sandy beaches, old lawns, and gardens. Common in pine plantations.
Rooted in soils from pure clays and sands to loam, organic substrate in swamps. Abundant in areas of calcareous bedrock.

Height variable to 65 cm. Stem slender to sturdy, sometimes greyish-magenta towards the base.
Leaves variable, 3 - 10, more or less clasping the stem, largest leaves near the middle of the stem; elliptic or narrowly lanceolate, plicate and veiny. Leafy bracts elliptic or narrowly lanceolate, the lower ones longer than the flowers.
Raceme to 30 cm., one-sided, tapering, flowers few to numerous. Flowers whitish-green, often streaked with purple and rose-red, lip constricted near middle, lower part fleshy, tip with raised fleshy callus. No spur.

One of our most common orchids, so abundant that people no longer record its presence. Great variation in stature and flower colour. Rhizomes may go dormant and reappear after a three year absence. Appearance of plants is strongly correlated with more open habitat and with amount of rainfall the previous August and September.

Orchids of Ontario
The Canadian Field-Naturalist Vol III - 1
The Orchids of Bruce & Grey