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DescriptionThis herbaceous perennial plant is about 1-2½' tall, branching occasionally. The stems are light green to reddish purple, terete, and glabrous (var. longistylis) to hairy (var. villicaulis). The alternate leaves are ternately compound; the lower compound leaves are up to 9" long and 9" across, while the upper compound leaves are much smaller in size. Each compound leaf is divided into 3 compound leaflets; the terminal compound leaflet is the largest. Each compound leaflet is further divided into 3 subleaflets; the terminal subleaflet is the largest, sometimes appearing to be divided into 3 even smaller subleaflets. The subleaflets are 1-4" long, ½-1½" across, and lanceolate to oval-ovate shape in shape; their margins are coarsely serrated-crenate or shallowly cleft. The upper subleaflet surface is yellowish green to green and nearly glabrous (var. longistylis) to moderately covered with appressed hairs (var. villicaulis). The petioles of compound leaves are light green to reddish purple and up to 6" in length. The petiolules of leaflets are light green to reddish green and up to 2" long, while those of subleaflets are nearly sessile to ¼" (6 mm.) long. The foliage of this plant releases a mild anise fragrance when it is rubbed. The upper stems terminate in compound umbels of white flowers about 1½-3" across. There are about 3-6 umbellets per compound umbel on rays (floral stalks) up to 2" long. An umbellet has 7-16 flowers that are clustered together on rays (floral stalklets) up to ¼" (6 mm.) long. Each flower (about 3 mm. across) has 5 white petals with incurved tips, 5 white stamens, a pistil with a divided white style (stylopodium), and an insignificant calyx that is light green. At the base of each compound umbel, there are several linear-lanceolate bracts with ciliate margins; they are up to 8 mm. in length. At the base of each umbellet, there are several linear-lanceolate bractlets with ciliate margins; they are also up to 8 mm. in length. The blooming period occurs during the late spring or early summer, lasting about 2-3 weeks. Afterwards, the flowers are replaced by 2-seeded fruits (schizocarps). While these fruits are still immature, the persistent divided style is 2.0-3.5 mm. in length (it is smaller than this when the flowers are still in bloom). The small seeds are narrowly ellipsoid-oblanceoloid, 5-ribbed, and slightly bristly along their ribs. The root system consists of a cluster of fleshy roots with a strong anise fragrance.