What is black cohosh?

Black cohosh is a North American native flowering plant. Actaea racemosa and Cimicifuga racemosa are its scientific names, and it's also known as black bugbane, black snakeroot, baneberry, and fairy candle.
Its flowers and roots were widely used in traditional Native American medicine, and it is now a popular women's health supplement that is said to help with menopause symptoms, fertility, and hormonal balance.
It could be effective because it works as a phytoestrogen, which is a plant-based compound that mimics the action of the hormone estrogen. However, there is some disagreement about whether black cohosh is a true phytoestrogen.
Regardless, black cohosh appears to be helpful in alleviating menopausal symptoms. However, evidence for its other applications is lacking.