Green Horizons

Medicinal herbs hold significant potential as profit sources for Missouri landowners pursuing production through the agroforestry practices of forest farming or alley cropping. Ginseng, goldenseal or black cohosh, for example, can be planted in between rows of pecan or black walnut trees in an alley cropping setting, or established within a wooded area in a forest farming practice.

One of the nation’s most comprehensive research studies on the herb black cohosh is being conducted at the University of Missouri’s Southwest Research Center, Mt. Vernon, Mo. Located in the Ozark region of the state, the farm is an ideal setting for the cultivation and study of this native species, a project coordinated by University of Missouri Center for Agroforestry collaborator Andrew Thomas. The herb black cohosh, or Actaea racemosa (formerly named Cimicifuga racemosa), is native to North America, and its roots and rhizomes are widely used in the treatment of menopausal symptoms.

Black cohosh flowering under shade structure at the Southwest Research Center, Mt. Vernon, Mo.

"Black cohosh is one of the top five medicinal herbs grown in North America and used in Europe, and the species is being ravaged by poachers and trespassers," said Thomas. "This overharvesting of naturally occurring black cohosh is threatening the species. We’re one of the few institutions studying the cultivation of this plant in an effort to increase profit potential for landowners and to prevent devastation to the crop by poaching."

Found naturally in parts of Missouri and more abundantly throughout the Appalachian region, the root of the black cohosh plant is harvested and sold in health and specialty food stores as a remedy to menopausal symptoms. The export market overseas is the primary market for the herb, with 95% of the black cohosh harvested in North America exported to Europe, where it is prescribed by doctors.

"People are underestimating the cash value of the black cohosh industry," says Thomas. "It has powerful potential, and current and future research will continue to solidify this assumption."

Black cohosh has been medically proven as an effective aid to menopausal women, and is continuing to increase in demand, due in part to recent medical studies to explore possible harmful side effects for the heart with traditional chemical hormone replacement therapy. One of the experiments at the Southwest Center is to expand outward from root harvesting and evaluate the potential of the natural medicinal compounds found within other tissues of the plant. This tissue research, combined with cultivation studies, places UMCA on the forefront of medical herb studies.

A healthy black cohosh ribozome.

"Our research indicates there may be as much as two to three times more of certain medicinal compounds in the leaf of the black cohosh plant as is found in the root, and 50 times the amount of compound in the flower than the root," said Thomas. "Not only could these compounds bring a higher price than the root, but harvesting the leaves or flower means the plant is not removed from the ground and can continue to grow."

Thomas began the cultivation project in 1999 and is working with nine different experiments at the Southwest Center, including cultivation in a shade house and a forest farming setting. He calls the herb "fairly simple to grow," and said it requires good drainage to prevent disease and rotting of the fleshy, thick root.

Retail market prices for black cohosh in pill form are $9-$11 per 60-tablet bottle. The supplement is also sold in tea and dried raw form at health and specialty food stores.

Similar to ginseng cultivation, black cohosh typically must be at least three years old to harvest the root and plant. One of Thomas’ research projects involves testing the chemical compound of the plant to determine if a significant amount of medicinal compound can be harvested by growing the plant as an annual. The outcome may be the ability to plant black cohosh in the fall and harvest it the following year.

Black cohosh is sold in pill, root, tea or liquid form at retail health food and specialty food stores. Photo: Clovers Natural Market, Columbia, Mo.

In addition to collaboration with the Center for Agroforestry, black cohosh research at the Southwest Center is also supported by the Center for Phytonutrient and Phytochemical Studies, a consortium between the University of Missouri and the Missouri Botanical Garden.

"There are still so many unanswered questions about cultivating this herb," Thomas says, "but that’s part of the fun of doing the work and the research."

For more information about black cohosh research at the University of Missouri Southwest Research Center, Mt. Vernon, Mo. visit http://aes.missouri.edu/swcenter/fieldday/report.stm, Horticulture Research section.

To learn more about forest farming practices and the value-added crops that can be produced through them, visit www.centerforagroforestry.org and select Profit in Agroforestry. Andrew Thomas’ published research papers on black cohosh will be available from this site soon.

Forestry Fact: The traditional American woodframe home contains more than 13,000 board feet of wood products.