Found growing throughout most of North America, excluding the far western and northeastern states, this is an uncommon species. Found in undisturbed prairies or dunes, it prefers loose, sandy soil or gravel. The soft fuzzy leaves are long, narrow, and in pairs along a 2-foot stem tinged with purple. Spherical clusters of yellow-green flowers appear at the top of the plant in early summer, followed by narrow pods full of seeds attached to silky tufts, which send the seeds airborne when the pods split open. The most prominent part of the flower is the calyx tube under the tiny flower petals. The main pollinator of this species is the bumblebee, and it is a favorite of the milkweed longhorn beetle. As with others in the family, the leaves contain bitter, milky sap.