Coefficient of Conservatism:
Coefficient of Wetness:
In forests of all kinds: conifers, hardwoods, mixed; moist or dry; from sandy oak-hickory or red pine to wet cedar-hemlock; often common in pine and spruce forests on old dunes as well as in beech-maple stands.
Two varieties occur in Michigan, the widespread var. maculata, with the middle lobe of the lip not or at most slightly expanded and floral bracts mostly 0.5–1 mm long, and var. occidentalis (Lindl.) Ames, found in the Upper Peninsula and northern Lower Peninsula, with the middle lobe of the lip clearly expanded and floral bracts mostly 1–2.8 mm long. Variety occidentalis flowers ca. 2–4 weeks earlier than var. maculata when they occur in the same region. In addition to the two varieties, several color forms occur; the most striking, occurring in the var. occidentalis, is all yellow but for the white lip (f. flavida (Peck) Farw.)