Corallorhiza macraei A. Gray

Racemes 10–67 cm. Flowers 5–35, showy; sepals and petals open, spreading, usually not nodding; sepals 8–18 mm; petals 7–18 mm; lip 7–16.5 × 4.4–8.5 mm; column 4–6.5 mm. Capsules 12–30 mm. 2n = 42.

Flowering spring--early summer. Coniferous, deciduous, and mixed woods, lakeshores, swamps; 0--2600 m; Alta., B.C., Man., Nfld. and Labr. (Nfld.), Ont., Que., Sask.; Calif., Colo., Idaho, Mich., Minn., Mont., Nev., N.Mex., N.Y., N.Dak., Oreg., S.Dak., Tex., Utah, Wash., Wis., Wyo.

A parasitic wasp (Pimplinae, Ichneumonidae) has been found visiting flowers and removing pollinia of Corallorhiza striata var. striata, our most striking and largest flowered coral-root (J. V. Freudenstein 1997).