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The Orchidaceae is widely distributed but is most diverse in the tropics where members are frequently epiphytes. The Orchidaceae is the most diverse family of vascular plants with (at last count) 775 genera and 19,500 species. Vanilla flavoring is extracted from the fruits of Vanilla planifolia. But the greatest economic importance of the family arises from the use of its members as ornamentals (e.g., Cattleya, Dendrobium, Paphiopedilium, Phalenopsis, Cymbidium, Oncidium).

All the orchids in our flora are terrestrial herbs, most of which are strongly mycorrhizal, and some of which are mycoparasitic (Corallorhiza). The dependence on mycorrhizae and the fragility of these fungal connections make transplantation almost impossible. Moreover, even the slight tug necessary when picking the flower can disrupt the fungal connections and kill the entire plant. Therefore, wild orchids must always be left undisturbed.

Leaves, when present, are generally few, alternate, simple, entire, with parallel venation, and sheathing at the base. The flowers are usually bisexual with bilateral symmetry. There are 3 sepals (usually one is larger and uppermost) and 3 petals (usually one is larger and lipped or pouched and lowermost). The stamens are fused to the style and stigma to form the "column," to which is attached the single fertile anther (2 in Cypripedium) at the back or tip. Each fertile anther bears two pollen sacs often separated by a broad connecting band of tissue. The pollen in each pollen sac adheres into 1-4 masses called pollinia, which often have a stalklike base. There are 3 stigmas that generally form a sticky concave to convex surface on the lower side near the tip of the column. The 3-chambered inferior ovary matures into a dry capsule with a huge number of minute seeds.

Corallorhiza maculata	Goodyera oblongifolia	Listera cordata	Platanthera dilatata	Platanthera stricta