Missouri has two species of sweet cicely, which can be hard to tell apart. Both are perennial herbs with umbels of small white flowers, fernlike leaves, and sweetly aromatic, carrotlike roots. Flowers minute, white, massed on simple umbels. Blooms April–June. Leaves fernlike: twice ternately compound (in 3 sections, 2 lateral, 1 terminal, all 3 divided again into 3 sections), coarsely toothed, the lateral leaflets on a short stalk, the terminal on a longer one; aromatic. Root carrotlike, often aromatic with an anise or licorice scent.
Anise root (O. longistylis) is our most common sweet cicely. Its roots are strongly anise-scented, and the styles of the flowers are longer than the petals at flowering time. It is scattered to common nearly statewide.
Woolly sweet cicely (O. claytonii) apparently is far less common in our state. It usually smells much less strongly of anise, and although the stamens often protrude from the flowers, the styles are shorter than the petals. It is most commonly found north of the Missouri River.