A rather inconspicuous orchis with small flowers, the stem usually stout, 10 inches to 3 feet high. Leaves lanceolate, pointed, 3 to 10 inches long, one-half to 1 ¾ inches wide. Flowers numerous in a narrow terminal spike, small, greenish or greenish yellow; sepals and petals free and spreading, ovate, blunt; lip entire, lanceolate, blunt, about one-fourth of an inch long; spur about as long as the lip, blunt, slightly incurved or often thickened at the end (clavate).
The Tall White Bog Orchis (Limnorchis dilatata (Pursh) Rydberg) is usually more slender, with small white flowers; the ovate or lanceolate sepals nearly one-fourth of an inch long; petals lanceolate, pointed; lip entire, dilated or obtusely three-lobed at the base, blunt at the apex, about as long as the blunt and incurved spur. In similar situations, but southward only to Maine and New York.
Memoir 15 N. Y. State Museum
A. Tall Leafy Green Orchis - Limnorchis hyperborea