This perennial member of the orchid family blooms from June to August. This species is found throughout the eastern part of North America and is documented in over half of the counties in Pennsylvania. Though rarely seen, it is not listed as threatened or endangered in the state.

The plant produces from 1-5 vertical narrow stem leaves. The stem is smooth. It can vary from 8 to 24 inches tall. There is also a long thin flower stalk or spike with up to 60 small inconspicuous yellow-green flowers. Smaller numbers of flowers, however, are more common. There are three petals and three sepals. The lower petal or labellum of each flower has a prominent low round bump or tubercle in the center. The edges of the lower petal also have rounded teeth. A nectar spur extends out of the back of the flower that forms from a modified sepal. The flower has a sweet, perfume-like fragrance. Thus this orchid is usually detected by smell before it is seen.

This species is found in meadows, floodplain forests, shorelines, swamps, thickets and marshes where there is abundant sunlight. Since natural disturbances to the forest create such sites, it is often found in such areas. Those plants that grow in more shaded areas usually have darker green leaves. There are two varieties of this species, one with higher density of flowers than the other. There are also minor differences in the form of the flowers. Intermediate forms are common. In areas where it is rare its continued existence can be threatened by habitat destruction and by unscrupulous orchid collectors. It is also called the Northern tubercled orchid or the Southern rein orchid.