Osmorhiza longistylis (Torr.) DC.

Anise Root

Osmorhiza_longistylis_plant.jpg
STATS

Native
CC = 3
CW = 3
MOC = 71

© SRTurner

Family - Apiaceae

Habit - Perennial forb with clusters of tuberous-thickened roots. Plants (especially roots) usually anise-scented.

Stems - Ascending to erect, to 1 m tall, glabrous to densely pubescent with spreading hairs, branching.

Osmorhiza_longistylis_stem.jpg

© DETenaglia

Osmorhiza_longistylis_roots.jpg Roots.

© DETenaglia

Leaves - Alternate and often basal, compound, usually petiolate, the uppermost leaves often sessile or nearly so. Sheathing bases not or only slightly inflated. Leaf blades 4-25 cm long, broadly triangular-ovate in outline, ternately or ternately then pinnately 2 or 3 times compound with distinct leaflets, these 3-10 cm long, mostly 1 cm or more wide, ovate to lanceolate or oblong-lanceolate, shallowly to moderately several-lobed and sometimes also with a pair of deep, basal lobes, the margins also toothed, shallowly cordate to long-tapered at the base, narrowed or tapered to a sharp point at the tip, the upper and undersurface sparsely to moderately pubescent with stiff, spreading hairs, especially along the main veins and margins.

Osmorhiza_longistylis_leaf1.jpg Portion (1/3) of leaf, adaxial.

© SRTurner

Osmorhiza_longistylis_leaf2.jpg Leaflet abaxial.

© SRTurner

Osmorhiza_longistylis_sheath.jpg Petiolar sheath.

© SRTurner

Osmorhiza_longistylis_leaf.jpg Pressed leaf.

© DETenaglia

Inflorescence - Compound umbels. Umbellets sometimes all or partially of staminate flowers. Involucre of 1-6 bracts, rarely absent, the bracts 3-20 mm long, usually reflexed, linear to lanceolate, with a sharply pointed tip, densely pubescent with stiff, spreading or ascending hairs along the margins and midvein. Rays 3-6, often somewhat unequal in length, usually ascending. Involucel of 4-7 bractlets, these shorter than the flower stalks, similar to the bracts. Flowers 7-19 in each umbellet (usually 7 or fewer perfect, the rest staminate), the stalks 2-5 mm long at flowering, the central flower usually sessile and staminate, those of the perfect flowers elongating to 12 mm at fruiting.

Osmorhiza_longistylis_inflorescence.jpg Inflorescence.

© DETenaglia

Osmorhiza_longistylis_bracts.jpg Involucre (occasionally absent).

© DETenaglia

Osmorhiza_longistylis_inflorescence2.jpg Inflorescence.

Involucels present but involucre is absent in this specimen.

© SRTurner

Flowers - Sepals absent. Petals 5, oblanceolate to obovate, rounded or with an abrupt, minute point at the tip, white, subequal but typically one or two larger than the others, to 2 mm long and broad. Stamens 5, alternating with petals, spreading to erect. Styles 2 mm long in flower, longer than petals.

Osmorhiza_longistylis_flowers.jpg Flowers close-up.

© SRTurner

Osmorhiza_longistylis_styles.jpg Persistent styles on immature fruit.

© DETenaglia

Osmorhiza_longistylis_diagram.jpg Stamens and styles.

© SRTurner

Fruits - Schizocarps 10-22 mm long, linear to narrowly oblong-oblanceolate in outline, long-tapered at the base, tapered to a beak at the tip, flattened laterally, glabrous or pubescent with stiff, ascending bristles along the ribs, greenish brown to dark brown or black with green to dark brown ribs, the mericarps sometimes slightly arched or curved, somewhat narrowed along the commissures, with 5 narrow, angled ribs, these lacking wings.

Osmorhiza_longistylis_fruits.jpg Fruits.

© SRTurner

Flowering - April - June.

Habitat - Bottomland and mesic forests, often in ravines, streambanks, shady, moist, disturbed areas.

Origin - Native to the U.S.

Lookalikes - Osmorhiza claytonii.

Other info. - This licorice smelling plant can be found throughout Missouri, as well as much of the northeastern 2/3 of the continental U.S. It ranges into Canada as well. All parts of the plant exhibit a sweet fragrance, which many claim is stronger than that of the closely related O. claytonii. The two plants are virtually identical in appearance, but with a little practice can be reliably distinguished by the length of the styles (see diagram above). Those of C. claytonii are much shorter. Be sure to examine the styles, which are forked in a V-shape, rather than the anther-topped stamens, and be aware that many of the flowers do not have styles. This species is much more common in Missouri than O. claytonii.

The licorice aroma of the plant is due to the chemical compound anethole, which is also present in fennel, anise, and true licorice. The plants have long been used as both flavoring and in traditional medicines. Leaves are sometimes used as a salad green, and minced root can be used as a substitute for fennel seeds. The genus name Osmorhiza is derived from the Greek words osme (odor) and rhiza (root). The specific epithet refers to the long styles.

Photographs taken in the Ozark Scenic Riverways, Shannon County, MO., 5-20-03, and in Columbia, MO., 4-25-04 (DETenaglia); also along the Katy Trail southeast of Dutzow, Warren County, MO, 4-11-2012 and 4-22-2020, and 4-22-2021, and Glassberg Conservation Area, Jefferson County, MO, 5-11-2013 (SRTurner).