Caulophyllum, Greek, stem-leaf, the stem seeming to form a stalk for the great leaf.

A smooth, perennial herb that comes up in early spring a dark purplish color, fading to green. Rich open woods. New Brunswick to Minnesota, south to the Carolinas and Missouri. Common in northern Ohio. April, May.


Thickened, matted.


Erect, smooth, at first purplish, covered with a bloom, one to three feet high, with two or three sheathing scales at the base, a large, ternately compound leaf near the summit and generally a smaller similar one near the base of the inflorescence.


Large, ternately compound, divisions long-petioled, the ultimate segments thin, oval, oblong or obovate, three to five-lobed near the apex.


Borne in a loose, open, terminal cluster of yellowish purple flowers, one-half to three-fourths of an inch across.

Blue Cohosh. Caulophyllum thalictroides

Blue Cohosh. Caulophyllum thalictroides


Of six sepals, with three or four small bracts at the base.


Of six small, thick, hooded petals.


Six; anthers oblong.


One; style short; stigma minute.


Large, globose seeds resembling berries, blue with a bloom, borne on stout stalks a quarter of an inch long.

The first appearance of the Blue Cohosh is somewhat forbidding, for the whole plant comes up a dark purplish green covered with a whitish bloom and so unlike any of its neighbors that the first impression of it is that it must be poisonous. When it gets well above ground, however, it loses its unpleasant aspect and becomes a pretty plant. The color of the flower is dull, one may call it greenish yellow or yellowish purple, but the fruit is a bright-blue berry, on a short, thick fruit-stalk. The fruit resembles a drupe but really is a naked seed with the outer coat fleshy. Originally there are two seeds in the developing ovary. As these grow they burst their covering, which soon withers away, and they continue their growth as naked seeds. Usually one gets the better of his brother and finishes the race alone, plump, round, and blue.