Blue cohosh, Caulophyllum thalictroides, is a woodland wildflower that blooms at the same time as other early spring wildflowers in the forests of the eastern and midwestern US. We saw it recently in the Indiana Dunes National Lakeshore. Blue cohosh obtained its name from the blue-purple color of its smooth, rather odd-looking stems and its blue, toxic berries. There are three “cohosh” species in the eastern forest flora – blue, white (Actaea pachypoda) (which we also saw in the Dunes) and black (Actaea racemosa -- formerly known as Cimicifuga racemosa). They received their names not because they are botanically related – blue cohosh is in the barberry family (Berberidaceae) while white and black cohoshes are in the buttercup family (Ranunculaceae) – but rather from the Native American tribes who used them as medicinals. Blue and black cohosh in particular are used as labor stimulants, often in a preparation that includes both herbs; white cohosh was more often used for colds and coughs, but it’s also recorded as being a labor stimulant by one tribe.
Blue cohosh has a long-standing reputation among midwives, not only as a medication that can be taken to start an overdue labor or assist a weak uterus in childbirth, but also as an antispasmodic to relieve excessive uterine cramps during menstruation or relieve pain in childbirth. This dual action, typical of a number of herbs, is described as “tonic” activity, or an action that normalizes body functions. Tonic activity is also attributed to herbs like ginseng, which is thought to normalize overall body function (blue cohosh is sometimes called yellow ginseng or blue ginseng). The uterine stimulating and antispasmodic activities are attributed to different phytochemicals in the plant.
Blue cohosh (Caulophyllum thalictroides)
This array of activities makes blue cohosh sound like a very useful plant. But it has a darker side. For one thing, it has also been used to cause abortions because of its ability to stimulate uterine contractions. In fact, herbalists recommend that it be avoided during and up until the end of pregnancy for this reason. It contains a number of phytochemicals that could cause birth defects, and the plant extract has been shown to cause birth defects in lab animals, so it’s fortunate that it is traditionally avoided early in pregnancy. It can also cause effects similar to an overdose of nicotine, which was noted in a case of a young woman using it for an abortion. There are also reports of health problems in babies born after mothers used blue cohosh, though it is still uncertain whether blue cohosh is actually at fault in this case.
Whether the case reports truly represent blue cohosh toxicity or are simply unfortunate coincidences, the potential for nicotine-like toxicity in blue cohosh makes it something to avoid. White cohosh is also something to be avoided, which you might deduce from one of its other names, baneberry (another name is doll’s eyes, from the fruits, which are white with a black spot). Although blue and white cohosh are in different families, there are actually some similarities to the way the plants look. Blue cohosh has very smooth purplish stems, and grows about a foot or two high, with compound leaves and rounded leaflets. White cohosh is about the same size, has compound leaves, and also has a very smooth stem, which has a whitish tinge. The actual fruits and flowers are quite different, of course, but it was rather amusing to note the two species growing right across the trail from each other in one of our trips to the Indiana Dunes. Both are early spring wildflowers, though the white cohosh blooms a week or so later than the blue. Black cohosh, although related to white cohosh, has a very different look, and blooms much later in the summer.
While blue cohosh is not the most scientifically validated herbal remedy, it is a lovely plant to encounter in the forest, and it can be grown at home if you have a moist and shady area. It may take a while to germinate, and it takes two years before the plant matures, but it has a unique presence. White cohosh, another very attractive plant, can also be cultivated, in shady areas with rich soil. Do keep your kids and grandkids away from the berries of either of these, though!
White Cohosh or White Baneberry (Actaea pachypoda)
Charlotte
In the eastern US there is also a very close relative of white cohosh, or white baneberry, known as red baneberry (Actaea rubra). The only really obvious difference is the red fruit, in contrast to the white fruit of white cohosh, though there are subtle differences, such as the thickness of the flower stalks (pedicels and peduncles) and other minor aspects of the small flowers. Vegetatively, they are virtually indistinguishable. (The matter is even worse -- the fruits of red baneberry are white on rare occasions, and those of white baneberry are rarely red). In the Indiana Dunes, red baneberry is extremely rare, while white baneberry is fairly common.
Michael
