Stems: Erect, branched, smooth, rarely hairy, with milky sap, up to 5 feet tall.
Leaves: Opposite, simple, lanceolate to oblanceolate, pointed at the tip, narrowed or rounded at the base, without teeth, smooth or hairy on the lower surface, with milky sap, up to 4 inches long, up to 1 inch wide, with short stalks.
Flowers: Several borne in umbels, pink to pinkish red, hour-glass-shaped, up to 1/3 inch long, borne on smooth stalks.
Sepals: 5, greenish, turned downward.
Petals: 5, pink to pinkish red, associated with a 5-parted central column.
Stamens: 5, associated with the central column.
Pistils: Ovaries 2, superior.
Fruits: Follicles smooth, up to 5 inches long, containing several seeds with silky hairs at one end.
Notes: The leaves, when gathered young, can be cooked and eaten as a vegetable. The roots are eaten by muskrats.