Blue Cohosh – Caulophyllum thalictroides

Overall At-Risk Score:45

Latin Name:

Caulophyllum thalictroides (L.) Michx.¹

Common Name:

Blue Cohosh; Papoose Root


Berberidaceae (Barberry family)

Geographic Region:

Manitoba to northern Arkansas, Quebec to South Carolina – AR, DE, IA, IL, IN, KY, MA, MD, ME, MI, MN, MO, NC, NH, NJ, NY, OH, PA, SC, TN, VA, WI, WV¹


Shaded, moist (not necessarily well-drained), open woodlands in the Eastern Hardwood Forest²




Inconspicuous purplish green flowers bloom in mid April, ripening into a brilliant blue fruit that holds onto the plant through summer. Each fruit has two seeds that outgrow the ovary shortly after seed development begins, growing into the large blue seeds positioned above the leaves.²

Ability to withstand disturbance and over harvest:

C. thalictroides requires moist soils and deep shade, which means logging in forestlands is a threat to C. thalictroides populations. Overharvesting is a threat as well, as C. thalictroides seeds require double stratification and may take up to three seasons to reach reproductive maturity.

Status of Endangered/Threatened(by state):

Listed as Threatened in the state of Rhode Island¹

Part of Plant Used/Active Medicinal Compounds:

The roots and rhizome are used, as they contain the highest concentration of active alkaloids and triterpence saponins. Traditionally, Blue Cohosh was used “in many native communities of North America … to induce childbirth, ease the pain of labor, rectify delayed or irregular menstruation, and alleviate heavy bleeding and pain during menstruation.”³

The large seeds can also be roasted and brewed similar to coffee, although it lacks caffeine or other active stimulants.

Demand and Relative Acreage Needed to Meet Demand:

Demand for Blue Cohosh root is very low compared to many of our native perennial herbs, but is steadily growing.

Wild Harvesting Impact On Other Species and Lookalikes:

C. thalictroides is often confused with a similar species, C. giganteum, which looks similar in the leafs and growth pattern. But C. giganteum is significantly larger than C. thalictroides and has consistently dark purple flowers, and flowers 2-3 weeks earlier than C. thalictroides, and does not contain the desired medicinal compounds.
C. thalictroides also shares a lot of visual similarities to the Meadow Rues, and is difficult to distinguish without visible flowers or fruit. But Meadow Rues often have much longer petioles connecting the leaflets to the main stem. ²

Recommendations for industrial and home use:

Consumers should be very careful in ingesting this herb, and should rely on sustainably farmed sources rather than wild harvested roots.

  1. USDA: