Flower:

Flowers are in loose rounded clusters at the end of stems that arise from a leaf joint. Individual flowers are about ½ inch across with 6 yellowish green petal-like sepals and 6 yellow stamens in a ring around the green center. The true petals are tiny (barely longer than the stamens), greenish, and sit between the sepals and stamens.

Leaves and stem:

Leaves are compound in groups of 3, each leaflet to 2½ inches long and wide, toothless and hairless, with 2 to 5 pointed lobes and a short stem. The base of the leaflet is rounded and often asymetrical, especially on the side leaflets.

The main stem is hairless and has many branches, with multiple branches joined at the same node. One plant can have multiple stems; they may be tinged purple or blue.

Fruit:

Fruit is a green berry, about 1/3 inch across, that ripens to a deep blue. The fruit is poisonous.

Notes:

Blue Cohosh leaves look similar to some other plants, including Early Meadow Rue and Tall Meadow Rue. Blue Cohosh has larger leaves than those 2 plants and is densely branched.