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DescriptionThis native perennial plant is about 1½2½' tall, branching occasionally. The upper stems are light green and pubescent, while the lower stems are often brownish green and coarsely hairy. These stems are round in circumference, rather than angular. There are a few basal leaves (produced during the spring) and alternate cauline leaves. The lower cauline leaves are trifoliate, while the upper cauline leaves are usually simple; they are rather irregular in shape. The simple leaves and leaflets of the compound leaves are up to 4" long and 3" across, becoming smaller as they ascend the stems. They are lanceolate to oval-ovate, coarsely serrated, and often cleft into 3 major lobes. Their margins are often shallowly cleft or incised as well. The basal leaves are similar to the cauline, except that they are always compound (either trifoliate or odd pinnate). The wrinkled upper surface of each leaf is either hairless or has scattered hairs that are very short and bristly; the lower surface is either hairless or has a few hairs along the major veins. The lower leaves have stout petioles up to 1" long, while the upper leaves have short petioles or they are sessile. At the base of each petiole, there are a pair of leafy stipules up to ½" long that are usually toothed along their margins. Each upper stem often terminates in 1-3 flowers; sometimes individual flowers are produced from the axils of the upper leaves. Each peduncle (flowering stalk) bears a single flower; this peduncle is up to 3" long and finely pubescent. Each flower is about ½" across, consisting of 5 bright white petals, 5 triangular green sepals, and numerous stamens surrounding a cluster of green carpels with elongated styles. The sepals are the same length or shorter than the petals; they are initially spreading, but curve downward with age. The anthers of the stamens are initially white, but they soon turn brown. The receptacle of each flower (the surface underneath the carpels) is pubescent. The blooming period occurs during the summer and lasts about 1-2 months. There is no noticeable floral scent. Each flower is replaced by a spheroid cluster of achenes with persistent styles that are hooked at their tips. This fruiting cluster spans about ¾" across; it is initially green, but eventually turns brown. The root system consists of a taproot and rhizomes; from the latter, vegetative offsets can be produced. This plant occasionally forms colonies.