The Endangered Herbs

The National Cancer Institute recently touted the new drug Taxol as the biggest therapeutic breakthrough of the past two decades. This drug, shown to be effective against several forms of advanced cancer, originally was derived from the bark of the Pacific yew tree (Taxus brevifolia). Until only a few years ago, the mode of harvest was terribly wasteful: Six 100-year-old yews had to be sacrificed for every patient treated. Had the harvest continued, it would have led to the speedy extinction of the wild yew in the Pacific Northwest.

Responding to the outcry of environmental groups as well as the desperate pleas of terminal cancer patients, the pharmaceutical industry found the means to extract the active ingredient from the yew’s needles. Today, many companies are raising their own yew trees rather than cutting down wild ones, and the results have been very green indeed: In 1996 alone, reports HerbClip(Jan. 16, 1998), global sales of Taxol exceeded $800 million.

The fate of many other medicinal plants appears to be far more dire. Approximately 80 percent of the world’s inhabitants rely on traditional plant-based medicines, according to the World Health Organization. The U.S. market for medicinal herbs is estimated at $1.6 billion. “Maintaining the supply of medicinal plants is a problem mainly because most medicinal plants are harvested from the wild, or wildcrafted,” writes David Taylor in E Magazine (Jan./Feb. 1998). “For many plants, this practice has been relatively benign for centuries, since those who use the plants have collected only what they need.

But as the trade has become market-oriented and international, the number of wildcrafters is outstripping natural production.”

A classic example is goldenseal, one of the world’s best-selling herbs. Widely used to treat infections, this small woodland plant grows plentifully in moist hardwood forests around the world. But large-scale collection combined with the expansion of timber harvests has made it increasingly difficult to find goldenseal in forests where it was once abundant. As HerbalGram (No. 41) reports, current demand in the United Kingdom alone threatens to decimate the species, since it takes decades to replenish the plant.

Another popular herb extracted from certain species of coneflower, echinacea (E. purpurea and E. angustifolia), is increasingly cultivated as a cure for colds and flus. Although annual sales have now topped $80 million, the herb is not considered endangered at the present time, though monitoring has been limited. However, wildcrafters searching for echinacea unwittingly harvest other endangered speciesóthe Tennessee purple coneflower and smooth coneflower, which share a strong resemblance to the more common echinaceas. Such collateral damage is fairly commonplace.

Ginseng, an extremely slow-growing root, is probably the most renowned of all medicinal herbs. Only the fully mature plant has medicinal value, according to Natural Health(March/April 1998), and maturity requires a minimum six years of growth. Cultivated ginseng makes up over 90 percent of total U.S. ginseng exports. This makes it easier to track. But with the more potent wild ginseng fetching $1,000 per kiloóthree times as much as cultivated ginsengópoaching activities have skyrocketed.

Indeed, American ginseng tops a recent list of endangered plants compiled by United Plant Savers, a Vermont-based team of concerned herbalists and conservation-minded citizens. (Goldenseal, Hydrastis canadensis, and wild yam, Dioscorea villosa, used to derive the anti-aging hormone DHEA, are second and third, respectively.) Beyond our borders, the Convention in Trade in Endangered Species (CITES) has begun to compile its own listing of rare medicinal plants as a stimulus for developing strategies for protecting these species. Such strategies include setting clear guidelines for harvesting and wildcrafting that can be enforced in the places the herbs grow, education on sustainable use for both consumers and growers, and development of high-quality cultivated substitutes for wild herbs.

But it’s the power of the market that may ultimately spur the preservation of these endangered plants. As wild-harvested herbs become more scarce, quality is likely to decline while prices increase, explains HerbalGram. This makes cultivation increasingly profitable. And with appropriate growing techniques, the quality of organically grown herbs can meet and even surpass that of their wild counterparts. As a result, growing medicinal plants may become a booming business.

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