Flower:

A single flower is at the end of a long naked stalk that arises from the whorl of leaves about midway up the plant. Individual flowers are ¾ inch across with 5 pointed, hairy, greenish white, petal-like sepals and numerous yellowish stamens around a green cone-like center. The cone is about twice as long as wide while the flower blooms. One plant has 2 to 8 flowers.

Leaves:

There are basal leaves, a whorl of 3 to 10 leaves about midway up the stem, and sometimes a pair of leaves on a flower stalk, all of similar shape, palmately compound in groups of 3. The basal leaves have long stems and are a little larger than the stem leaves; any leaves on a flower stalk are much smaller. Leaflets are deeply lobed in 3 to 5 parts, wedge-shaped at the base with the lobes fanning out, hairy, to 4 inches long.

Fruit:

The flower cone elongates up to 1½ inches. Fruit is a tiny brown seed attached to cottony fluff. The cottony cones persist through winter.

Notes:

Thimbleweed is easily confused with Tall Thimbleweed. The best way I've found to tell them apart is by the shape of the leaves. Thimbleweed leaflets are wedge-shaped at the base with the lobes fanning out. The outer lobes of Tall Thimbleweed leaflets are rounded with teeth along the tip half. Thimbleweed also rarely grows taller than 2 feet, where Tall Thimbleweed can reach nearly twice that.