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DescriptionThis native perennial wildflower is 2-5' tall and sparingly branched. The stems are medium green, terete, glabrous, and conspicuously veined. Alternate compound leaves occur along the stems that are odd-pinnate with 5-9 leaflets. The blades of these compound leaves are widely spreading to ascending; their outlined form extends to 1½' long and ¾' across. Generally, lower compound leaves are a little longer with wider leaflets than the upper ones. The compound leaves have stout petioles about 2-4" long; there is a sizeable sheath where each petiole joins the stem. The sessile leaflets are 1/8" to 1" across and 2½4½" long; they are linear to elliptic-oblong in shape and smooth to sparingly dentate along their margins. If teeth are present, there are up to 7 widely spaced teeth on each side of a leaflet. The upper surfaces of the leaflets are medium green and hairless, while their lower surfaces are pale green and hairless. The upper stems terminate in compound umbels of small white flowers on long naked peduncles. The compound umbels are slightly dome-shaped on the top. Each compound umbel spans 3-5" across, consisting of about 12 umbellets on slender stalks. Each umbellet has 10-20 flowers on short slender pedicels. The floral stalks are light green and hairless. There are 0-3 small linear bracts at the base of each compound umbel, and 0-3 tiny linear bractlets (bracteoles) at the base of each umbellet. Individual flowers span about 1/8" across, consisting of 5 white spreading petals, a short calyx, 5 stamens with white anthers, and a central pistil. The blooming period occurs from late summer to early fall and lasts about a month. The flowers are replaced by small hairless fruits (schizocarps) containing the seeds. Mature seeds are 4-6 mm. long, ovoid, and nearly flat on one side. The root system consists of a cluster of thick fleshy roots.